linoleic-acid and 1-1-diphenyl-2-picrylhydrazyl

Topics: Anti-Inflammatory Agents; Antioxidants; Biphenyl Compounds; Glycine max; Linoleic Acid; Lipoxygenase Inhibitors; Lipoxygenases; Molecular Docking Simulation; Picrates; Pyrazoles; Quinolones

Topics: A549 Cells; Antioxidants; Ascomycota; Bacillus subtilis; beta Carotene; Biocompatible Materials; Biphenyl Compounds; Candida albicans; Crystallography, X-Ray; Escherichia coli; Free Radical Scavengers; Fungal Proteins; Gold; Green Chemistry Technology; Hep G2 Cells; Humans; Linoleic Acid; Metal Nanoparticles; Microscopy, Electron, Scanning; Nanomedicine; Picrates; Spectroscopy, Fourier Transform Infrared; Staphylococcus aureus

This study investigated the effect of blanching pomegranate seeds (PS) on oil yield, refractive index (RI), yellowness index (YI), conjugated dienes (K232), conjugated trienes (K270), total carotenoid content (TCC), total phenolic compounds (TPC) and DPPH radical scavenging of the extracted oil. Furthermore, phytosterol and fatty acid compositions of the oil extracted under optimum blanching conditions were compared with those from the oil extracted from unblanched PS. Three different blanching temperature levels (80, 90, and 100 °C) were studied at a constant blanching time of 3 min. The blanching time was then increased to 5 min at the established optimum blanching temperature (90 °C). Blanching PS increased oil yield, K232, K270, stigmasterol, punicic acid, TPC and DPPH radical scavenging, whereas YI, β-sitosterol, palmitic acid and linoleic acid were decreased. The RI, TCC, brassicasterol, stearic acid, oleic acid and arachidic acid of the extracted oil were not significantly (

Topics: Antioxidants; Biphenyl Compounds; Carotenoids; Cholestadienols; Dietary Supplements; Eicosanoic Acids; Fatty Acids; Food Technology; Free Radical Scavengers; Linoleic Acid; Linolenic Acids; Oleic Acid; Phenol; Phenols; Phytosterols; Picrates; Plant Oils; Pomegranate; Refractometry; Seeds; Stearic Acids; Temperature

The aim of the present study was to prepare chitosan-PVA-silver nanoparticles (CS-AgNPs) through green method. Chitosan and PVA polymers acted as stabilizing agents. DLS and TEM analyses showed that CS-AgNPs were homogeneously dispersed in matrix with an average size of 190-200 nm. The CS-AgNPs were tested for their antioxidant and antibacterial properties and the results revealed that they exhibited higher antioxidant activity than CS powder. Moreover, CS-AgNPs were characterized by a low cytotoxicity effect at 5-200 μg/ml against Chinese Hamster Ovary (CHO-K1) cells. In addition, the prepared CS-Ag NPs were found to promote significantly the wound healing, as determined by the wound contraction ratio and histological examination. A significant improvement in wound healing progression and in oxidative stress damage were observed for CS, CS-PVA and CS-AgNPs-treated wound tissues, when compared to control and CICAFLORA®-treated groups. The wound healing effect could be attributed to the antibacterial and antioxidant synergy of AgNPs and CS. Results strongly support the possibility of using CS-AgNPs for wound care applications.

Topics: Animals; Anti-Bacterial Agents; Antioxidants; beta Carotene; Biphenyl Compounds; Chitosan; CHO Cells; Cricetinae; Cricetulus; Escherichia coli; Free Radical Scavengers; Free Radicals; Gels; Hemolysis; Humans; Iron; Linoleic Acid; Male; Metal Nanoparticles; Microbial Sensitivity Tests; Oxidative Stress; Oxygen; Picrates; Rats; Rats, Wistar; Silver; Silver Nitrate; Skin; Staphylococcus aureus; Wound Healing

We synthesized 6-amino-6-deoxychitosan (NCS) through a series of reactions from chitosan (CS). The antioxidant ability of CS and NCS were investigated in vitro, including that of DPPH-radical and hydrogen peroxide, reducing power, chelating abilities and inhibition of lipid peroxidation. As expected, after the introduction of amino groups, antioxidant ability had improved significantly. Especially, scavenging effect against DPPH-radical and hydrogen peroxide of NCS were 97% and 92% at 1.6mg/mL, respectively. Moreover, inhibition of lipid peroxidation was 57% at 0.1mg/mL. And the reducing power of NCS was 0.68 at 0.8mg/mL. Meanwhile, inhibitory effects against four fungi were also tested. Antifungal activity of NCS were better than those of CS and antifungal activity had improved more than 20% at 0.5mg/mL against these four kinds of plant pathogens. Based on the above results, it was reasonable to speculate that the obtained antioxidant ability and antifungal activity of NCS might benefit from amino groups on chitosan backbone. These in vitro results suggest the possibility that NCS as antioxidant compound could be effectively alleviate oxidative stress and thus inhibit the oxidative mechanisms that lead to degenerative diseases.

Topics: Antifungal Agents; Antioxidants; Biphenyl Compounds; Chitosan; Fusarium; Hydrogen Peroxide; Iron Chelating Agents; Linoleic Acid; Lipid Peroxidation; Microbial Sensitivity Tests; Picrates; Structure-Activity Relationship

Topics: Antioxidants; Benzothiazoles; beta Carotene; Biphenyl Compounds; Cations; Chromatography, Gas; Free Radical Scavengers; Hydrogen-Ion Concentration; Hydrolysis; Linoleic Acid; Mass Spectrometry; Monosaccharides; Oligosaccharides; Oxidation-Reduction; Picrates; Polysaccharides; Solanum tuberosum; Sulfonic Acids; Temperature; Time Factors; Waste Products

Topics: Antioxidants; beta Carotene; Biphenyl Compounds; Drugs, Chinese Herbal; Enzyme Inhibitors; Eucommiaceae; Inhibitory Concentration 50; Linoleic Acid; Oxidation-Reduction; Picrates; Plant Leaves; Xanthine Oxidase

The aims of the current study were to evaluate the best technique for total phenolic extraction from Lavandula pubescens (Lp) and its application in vegetable oil industries as alternatives of synthetic food additives (TBHQ and BHT). To achieve these aims, three techniques of extraction were used: ultrasonic-microwave (40 kHz, 50 W, microwave power 480 W, 5 min), ultrasonic-homogenizer (20 kHz, 150 W, 5 min) and conventional maceration as a control. By using the Folin-Ciocalteu method, the total phenolic contents (TPC) (mg gallic acid equivalent/g dry matter) were found to be 253.87, 216.96 and 203.41 for ultrasonic-microwave extract, ultrasonic-homogenizer extract and maceration extract, respectively. The ultrasonic-microwave extract achieved the higher scavenger effect of DPPH (90.53%) with EC50 (19.54 μg/mL), and higher inhibition of β-carotene/linoleate emulsion deterioration (94.44%) with IC50 (30.62 μg/mL). The activity of the ultrasonic-microwave treatment could prolong the induction period (18.82 h) and oxidative stability index (1.67) of fresh refined, bleached and deodorized palm olein oil (RBDPOo) according to Rancimat assay. There was an important synergist effect between citric acid and Lp extracts in improving the oxidative stability of fresh RBDPOo. The results of this work also showed that the ultrasonic-microwave assisted extract was the most effective against Gram-positive and Gram-negative strains that were assessed in this study. The uses of ultrasonic-microwave could induce the acoustic cavitation and rupture of plant cells, and this facilitates the flow of solvent into the plant cells and enhances the desorption from the matrix of solid samples, and thus would enhance the efficiency of extraction based on cavitation phenomenon.

Topics: Anti-Bacterial Agents; Antioxidants; beta Carotene; Biphenyl Compounds; Chemical Fractionation; Citric Acid; Food Industry; Lavandula; Linoleic Acid; Oxidation-Reduction; Palm Oil; Phenols; Picrates; Plant Oils; Triolein; Ultrasonic Waves

Context We report the first ever chemical/biochemical study on Crocus mathewii Kerndorff (Iridaceae) - a Turkish endemic angiosperm. This plant has never been explored for its phytochemistry and bioactivities. Objective This study explores C. mathewii corm and aerial parts for the chemical and biological properties of hexane, ethyl acetate, methanol and water fractions of the extracts. Material and methods Plant material (20 g) was extracted by methanol (250 mL × 5, 3 days each) and fractioned into hexane, ethyl acetate, methanol and water. All fractions were subjected to β-carotene-linoleic acid, DPPH(·), ABTS(·)(+), CUPRAC, metal chelating and tyrosinase inhibition activities. Hexane fractions were submitted to GC-MS analysis. Results Ethyl acetate fractions showed excellent IC50 values in DPPH(·) (aerial 36.21 ± 0.76 and corm 33.87 ± 0.02 mg/L) and ABTS(·)(+) (aerial 33.01 ± 0.79 and bulb 27.87 ± 0.33 mg/L); higher than the IC50 of the standard α-tocopherol (DPPH 116.25 ± 1.97; ABTS 52.64 ± 0.37 mg/L), higher than BHA in DPPH (57.31 ± 0.25 mg/L), but slightly lower in ABTS (19.86 ± 2.73 mg/L). Methanol extract of aerial parts also showed higher activity than α-tocopherol in DPPH (85.56 ± 11.51 mg/L) but slightly less (72.90 ± 3.66 mg/L) than both the standards in ABTS. Linoleic (aerial 53.9%, corm 43.9%) and palmitic (aerial 22.2%, corm 18%) were found as the major fatty acids. Discussion and conclusion Some fractions of C. mathewii showed higher antioxidant activities than the standards. There is a need to explore more about this plant.

Topics: Antioxidants; Benzothiazoles; Biphenyl Compounds; Chelating Agents; Cholinesterase Inhibitors; Crocus; Fatty Acids; Gas Chromatography-Mass Spectrometry; Linoleic Acid; Monophenol Monooxygenase; Palmitic Acid; Phytotherapy; Picrates; Plant Components, Aerial; Plant Extracts; Plants, Medicinal; Solvents; Sulfonic Acids; Turkey

Context Dodonaea viscosa (L.) Jacq (Sapindaceae) has been used in traditional medicine as antimalarial, antidiabetic and antibacterial agent, but further investigations are needed. Objective This study determines the antioxidant and anticholinesterase activities of six compounds (1-6) and two crystals (1A and 3A) isolated from D. viscosa, and discusses their structure-activity relationships. Materials and methods Antioxidant activity was evaluated using six complementary tests, i.e., β-carotene-linoleic acid; DPPH(•), ABTS(•+), superoxide scavenging, CUPRAC and metal chelating assays. Anticholinesterase activity was performed using the Elman method. Results Clerodane diterpenoids (1 and 2) and phenolics (3-6) - together with three crystals (1A, 3A and 7A) - were isolated from the aerial parts of D. viscosa. Compound 3A exhibited good antioxidant activity in DPPH (IC50: 27.44 ± 1.06 μM), superoxide (28.18 ± 1.35% inhibition at 100 μM) and CUPRAC (A0.5: 35.89 ± 0.09 μM) assays. Compound 5 (IC50: 11.02 ± 0.02 μM) indicated best activity in ABTS assay, and 6 (IC50: 14.30 ± 0.18 μM) in β-carotene-linoleic acid assay. Compounds 1 and 3 were also obtained in the crystal (1A and 3A) form. Both crystals showed antioxidant activity. Furthermore, crystal 3A was more active than 3 in all activity tests. Phenol 6 possessed moderate anticholinesterase activity against acetylcholinesterase and butyrylcholinesterase enzymes (IC50 values: 158.14 ± 1.65 and 111.60 ± 1.28 μM, respectively). Discussion and conclusion This is the first report on antioxidant and anticholinesterase activities of compounds 1, 2, 5, 6, 1A and 3A, and characterisation of 7A using XRD. Furthermore, the structure-activity relationships are also discussed in detail for the first time.

Topics: Acetylcholinesterase; Antioxidants; Benzothiazoles; beta Carotene; Biphenyl Compounds; Butyrylcholinesterase; Chelating Agents; Cholinesterase Inhibitors; Crystallography, X-Ray; Free Radical Scavengers; Linoleic Acid; Molecular Structure; Phytochemicals; Phytotherapy; Picrates; Plants, Medicinal; Sapindaceae; Structure-Activity Relationship; Sulfonic Acids; Superoxides

Origanum dubium Boiss. is a flavouring herb widely used in Cyprus. In this study, both lipophilic and polar extracts of the aerial parts of O. dubium were investigated for their chemical contents and their antioxidant potential. Overall, 20 constituents were isolated and identified, belonging mainly to three significant classes of compounds: terpenes, phenolic derivatives, such as hydroquinone glycosides and flavonoids and alicyclic derivatives. None of them was previously reported as constituent of O. dubium The inhibitory potencies of all total extracts and the isolated compounds on lipid peroxidation and their interaction with 1,1-diphenyl-picrylhydrazyl (DPPH) activity is discussed. The polar extract showed strong interaction with DPPH stable radical and significant inhibition of lipoxygenase and lipid peroxidation.

Topics: Anti-Inflammatory Agents; Antioxidants; Biphenyl Compounds; Cyprus; Flavonoids; Glycosides; Hydroquinones; Linoleic Acid; Lipid Peroxidation; Lipoxygenase; Origanum; Phenols; Picrates; Plant Extracts; Plant Proteins; Terpenes

Consumption of phenolic compounds is associated with beneficial effects in humans even though many of them are poorly absorbed. The aim of this study was to investigate the in vitro antioxidant activity of tyrosol (T), resveratrol (R) and their acetylated derivatives (AcD), as increased lipophilicity has been reported to improve absorption. The chemically synthesized AcDs were evaluated by their ability to scavenge DPPH radicals, inhibit non-enzymatic linoleic acid peroxidation, inhibit human serum oxidation in the presence of copper ions and inhibit lipoxygenase activity. T showed an inhibitory effect only in serum oxidation, where the T-acetylated at aromatic-OH was the most active. The T-acetylated at aliphatic-OH and 3,5-diacetyl-R exhibited the most powerful effect in non-enzymatic linoleic acid peroxidation with IC50 values 2.4 mM ± 0.21 and 0.055 mM ± 0.0018, respectively. In all other tests R was the most potent among all its AcD and T. Increasing lipophilicity by acetylation improves antioxidant activity of phenolic compounds in non-enzymatic lipid peroxidation assays.

Topics: Acetylation; Antioxidants; Biphenyl Compounds; Free Radical Scavengers; Glycine max; Humans; In Vitro Techniques; Linoleic Acid; Lipid Peroxidation; Lipoxygenase Inhibitors; Oxidation-Reduction; Phenylethyl Alcohol; Picrates; Resveratrol; Serum; Stilbenes

Antioxidant activity of lactic acid bacteria is associated with multiple health-protective effects. Traditional indexes of chemical antioxidant activities poorly reflect the antioxidant effects of these bacteria in vivo. Cellular antioxidant activity (CAA) assay was used in this study to determine the antioxidant activity of cell-free supernatants (CFSs) of 10 Lactobacillus strains. The performance of the CAA assay was compared with that of four chemical antioxidant activity assays, namely, DPPH radical scavenging, hydroxyl radical scavenging (HRS), reducing power (RP), and inhibition of linoleic acid peroxidation (ILAP). Results of the CAA assay were associated with those of DPPH and ILAP assays, but not with those of RP and HRS assays. The inter- and intra-specific antioxidant activities of CFS were characterized by chemical and CAA assays. L. rhamnosus CCFM 1107 displayed a high antioxidative effect similar to positive control L. rhamnosus GG ATCC 53103 in all of the assays. The CAA assay is a potential method for the detection of antioxidant activities of lactobacilli CFSs.

Topics: Antioxidants; Biological Assay; Biphenyl Compounds; Cell-Free System; Free Radical Scavengers; Hep G2 Cells; Humans; Hydroxyl Radical; Lactobacillus; Linoleic Acid; Lipid Peroxidation; Oxidation-Reduction; Picrates

The extraction, purification and degradation of polysaccharides from Opuntia ficus indica cladodes, as well as the evaluation of their antioxidant and antiglycated activities in vitro were investigated. The optimization of the extraction showed that extraction by ultrasound at 40 °C presented the best carbohydrates yield. The degradation of the extracted polysaccharides was achieved by free radical depolymerization with H2O2 in the presence of copper(II) acetate for various reaction times. Sugar contents were determined by colorimetric assays. The macromolecular characteristics of the different isolated and degraded carbohydrates were carried by size exclusion chromatography (SEC/MALS/VD/DRI). These experiments showed that all samples are polysaccharides, which are probably pectins and that molecular weight (Mw) has decreased from 6,800,000 to 14,000 g/mol after 3 h of depolymerization without changing the structure. Preliminary antioxidant and antiglycated tests indicated that degraded polysaccharides for 2 and 3 h showed even better antioxidant and antiglycated activities.

Topics: Animals; Antioxidants; Biphenyl Compounds; Cattle; Chromatography, Gel; Glycosylation; Hydrogen Peroxide; Linoleic Acid; Lipid Peroxidation; Opuntia; Organometallic Compounds; Pectins; Picrates; Plant Stems; Serum Albumin, Bovine; Solutions; Sonication; Temperature

The study was focused on the activity of propolis from Amaicha del Valle, Argentina (ProAV) as a promoter and scavenger of Riboflavin (Rf)--photogenerated reactive oxygen species (ROS).. Through a kinetic and mechanistic study, employing stationary and time-resolved photochemical and electrochemical techniques, the protecting activity of ProAV was investigated.. In the absence of light and Rf, ProAV exerted a relatively efficient inhibitory effect on 1,1-diphenyl-2-picrylhydrazyl radicals and acts as a protector of artificially promoted linoleic acid oxidation. Under aerobic visible-light-irradiation conditions, in the presence of Rf as the only light-absorber species, a complex picture of competitive processes takes place, starting with the quenching of singlet and triplet electronically excited states of Rf by ProAV. The species O2(1 g), O2(•-), H2O2, and OH(•) are generated and interact with ProAV.. ProAV behaves as an efficient ROS scavenger. It is scarcely photo-oxidized by interaction with the mentioned ROS. Quantitative results indicate that ProAV is even more resistant to photo-oxidation than the recognized antioxidant trolox. Two dihydroxychalcones, mostly present in the ProAV composition, are responsible for the protecting activity of the propolis.

Topics: Antioxidants; Biphenyl Compounds; Chalcones; Chromans; Free Radical Scavengers; Hydrogen Peroxide; Light; Linoleic Acid; Oxygen; Phenol; Photochemistry; Photolysis; Photosensitizing Agents; Picrates; Promoter Regions, Genetic; Propolis; Reactive Oxygen Species; Riboflavin; Spectrometry, Fluorescence; Tryptophan

In this study, polysaccharides extracted from Cyclocarya paliurus leaves were modified to obtain its three acetylated derivatives, Ac-CP1, Ac-CP2, and Ac-CP3. The physicochemical characteristics and antioxidant activities of acetylated derivatives were investigated. The results of chemical and FT-IR spectrum analysis showed differences between acetylated derivatives and native C. paliurus polysaccharide, which revealed that the acetylation were successful. Relative to unmodified polysaccharide, the protein contents of acetylated derivatives decreased, while carbohydrate values increased. The molecular weight (Mw) of acetylated derivatives were approximately 1.05-1.09×10(6)Da and were mainly composed of Ara, Gal, Glc, Man, GalA. Ac-CP1 with relatively low degree of substitution (0.13±0.01) exhibited excellent antioxidant activity in DPPH radical assay (95.21±0.89%), and also had strong chelating activity on β-carotene-linoleic acid assay (34.64±2.07%) at 0.5mg/ml. In addition, scanning electron microscope (SEM) observations suggested that acetylation could change the morphology and structure of polysaccharides from C. paliurus leaves.

Topics: Acetylation; Antioxidants; beta Carotene; Biphenyl Compounds; Juglandaceae; Linoleic Acid; Picrates; Plant Leaves; Polysaccharides; Structure-Activity Relationship

Protein by-products from the extraction of lecithin from egg yolk can be converted into value-added products, such as bioactive hydrolysates and peptides that have potential health enhancing antioxidant, and antihypertensive properties. In this study, the antioxidant and angiotensin converting enzyme (ACE) inhibitory activities of peptides isolated and purified from egg yolk protein were investigated. Defatted egg yolk was hydrolyzed using pepsin and pancreatin and sequentially fractionated by ultrafiltration, followed by gel filtration to produce egg yolk gel filtration fractions (EYGF). Of these, two fractions, EYGF-23 and EYGF-33, effectively inhibited the peroxides and thiobarbituric acid reactive substance (TBARS) in an oxidizing linoleic acid model system. The antioxidant mechanism involved superoxide anion and hydroxyl radicals scavenging and ferrous chelation. The presence of hydrophobic amino acids such as tyrosine (Y) and tryptophan (W), in sequences identified by LC-MS as WYGPD (EYGF-23) and KLSDW (EYGF-33), contributed to the antioxidant activity and were not significantly different from the synthetic BHA antioxidant. A third fraction (EYGF-56) was also purified from egg yolk protein by gel filtration and exhibited high ACE inhibitory activity (69%) and IC50 value (3.35 mg/mL). The SDNRNQGY peptide (10 mg/mL) had ACE inhibitory activity, which was not significantly different from that of the positive control captopril (0.5 mg/mL). In addition, YPSPV in (EYGF-33) (10 mg/mL) had higher ACE inhibitory activity compared with captopril. These findings indicated a substantial potential for producing valuable peptides with antioxidant and ACE inhibitory activity from egg yolk.

Topics: Angiotensin-Converting Enzyme Inhibitors; Animals; Biphenyl Compounds; Chromatography, Gel; Egg Proteins; Free Radical Scavengers; Hydrogen Peroxide; Hydrolysis; Hydroxyl Radical; Iron; Linoleic Acid; Oxidation-Reduction; Pancreatin; Pepsin A; Peptidyl-Dipeptidase A; Picrates; Proteolysis; Sequence Analysis, Protein; Superoxides; Thiobarbituric Acid Reactive Substances; Thiocyanates

Guava jam enriched by the addition of concentrated grape juice in the proportion of 30% (w/w) (ENR) was studied for its antioxidant potential and rheological behavior. Total phenolics content, 1,1-diphenyl-2-picrylhydrazyl radical (DPPH(•)) scavenging activity and β-carotene-linoleic acid coupled oxidation assays were used to evaluate the antioxidant properties of the samples during storage for 90 days at room temperature (25°C).. The ENR showed a total phenolic content of 11.09 g GAE kg(-1) of jam at production, more than two-fold the phenolic content presented by the standard formulation (STA). For the ENR formulation the antioxidant capacity increased in almost 20% (P ≤ 0.05) with time on the β-carotene assay and decreased with time on the DPPH assay. The enriched guava jam exhibited a non-Newtonian shear-thinning behavior at temperatures ranging from 25 to 55°C, and, moreover, presented higher stability than the standard formulation when exposed to temperature variation.. ENR constitutes an original food product with a notable antioxidant potential, even greater than the potential presented by the standard guava jam, worldwide appreciated delicacy.

Topics: Antioxidants; beta Carotene; Biphenyl Compounds; Chemical Phenomena; Fruit; Functional Food; Linoleic Acid; Oxidation-Reduction; Phenols; Picrates; Psidium; Rheology; Vitis

Lipase-catalyzed acidolysis of p-coumaric acid with seal blubber oil (SBO) and menhaden oil (MHO) was carried out, followed by identification of major phenolipids in the resultant acidolysis mixture using high-performance liquid chromatography/mass spectrometry. Separation of phenolipid components from the resultant acidolysis mixture was achieved using flash column chromatography. The antioxidant activities of the phenolipids were examined in in vitro assays and biological model systems. The major phenolipids identified from acidolysis mixtures with both SBO and MHO included eight phenolic monoacylglycerols and eight phenolic diacylglycerols. Phenolipids derived from SBO and MHO generally showed good antioxidant potential in the systems tested. The prepared phenolipids exhibited high scavenging capacity toward 1,1-diphenyl-2-picrylhydrazyl (DPPH) and peroxyl radicals and displayed reducing power, strong inhibitory effect on bleaching of β-carotene, human low-density lipoprotein (LDL) cholesterol oxidation, as well as radical-induced DNA cleavage, thus suggesting that phenolipids derived from omega-3 oils may be used as potential stable products for health promotion and disease risk reduction.

Topics: Antioxidants; beta Carotene; Biphenyl Compounds; Cholesterol, LDL; Coumaric Acids; Diglycerides; DNA Damage; Fatty Acids, Omega-3; Fish Oils; Free Radical Scavengers; Health Promotion; Linoleic Acid; Lipase; Monoglycerides; Oxidation-Reduction; Phenols; Picrates; Propionates

Ellagic acid (EA, C14H6O8) is a natural dietary polyphenol whose benefits in a variety of diseases shown in epidemiological and experimental studies involve anti-inflammation, anti-proliferation, anti-angiogenesis, anticarcinogenesis and anti-oxidation properties. In vitro radical scavenging and antioxidant capacity of EA were clarified using different analytical methodologies such as total antioxidant activity determination by ferric thiocyanate, hydrogen peroxide scavenging, 1,1-diphenyl-2-picryl-hydrazyl free radical (DPPH) scavenging, 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging activity and superoxide anion radical scavenging, ferrous ions (Fe2+) chelating activity and ferric ions (Fe3+) reducing ability. EA inhibited 71.2% lipid peroxidation of a linoleic acid emulsion at 45 μg/mL concentration. On the other hand, butylated hydroxytoluene (BHT), butylated hydroxyanisole (BHA), α-tocopherol and ascorbic acid displayed 69.8%, 66.8%, 64.5% and 59.7% inhibition on the peroxidation of linoleic acid emulsion at the same concentration, respectively. In addition, EA had an effective DPPH• scavenging, ABTS+ scavenging, superoxide anion radical scavenging, hydrogen peroxide scavenging, ferric ions (Fe3+) reducing power and ferrous ions (Fe2+) chelating activities. Also, those various antioxidant activities were compared to BHA, BHT, α-tocopherol and ascorbic acid as references antioxidant compounds. These results suggested that EA can be used in the pharmacological, food industry and medicine because of these properties.

Topics: alpha-Tocopherol; Antioxidants; Ascorbic Acid; Biphenyl Compounds; Butylated Hydroxyanisole; Butylated Hydroxytoluene; Chelating Agents; Ellagic Acid; Emulsions; Free Radical Scavengers; Free Radicals; Hydrogen Peroxide; Iron; Linoleic Acid; Lipids; Oxygen; Picrates; Spectrophotometry; Superoxides; Thiocyanates; Time Factors

This study was designed to examine the in vitro antioxidant activity of essential oil and methanol extracts of Eucalyptus leucoxylon. Furthermore, the polar fraction of the extract was used as a reducing agent for the green synthesis of silver nanoparticles (Ag NPs). Antioxidant activities of the samples were determined by using three different test systems, namely DPPH and β-carotene/linoleic acid and reducing power. The structure and composition of the prepared Ag NPs were characterised by X-ray diffraction, scanning electron microscopy, transmission electron microscopy and UV-vis spectroscopy. Synthesised Ag NPs were almost spherical in shape with an average diameter of about ∼ 50 nm and synthesised within 120 min reaction time at room temperature.

Topics: Antioxidants; beta Carotene; Biphenyl Compounds; Eucalyptus; Linoleic Acid; Metal Nanoparticles; Methanol; Microscopy, Electron, Scanning; Microscopy, Electron, Transmission; Oils, Volatile; Oxidation-Reduction; Picrates; Plant Leaves; Silver; Temperature; X-Ray Diffraction

The beneficial effects of oyster extract against various disorders and diseases induced by oxidative stress have aroused great interest. In this article, ultrasonic-assisted enzymolysis was employed to produce polysaccharides of Crassostrea hongkongensis (CHP) and their antioxidant activity was investigated. A single-factor experiment and then a four-factor, three-level Box-Behnken design were first used to optimize ultrasonic extraction for polysaccharides. On the basis of ridge analysis, the optimum conditions are obtained as ultrasonic treatment time of 24 min, power of 876 W, temperature of 49°C, and material-solvent ratio of 1:6 (w/v). It is found that ultrasound pretreatment before protease hydrolysis was a great help to improve CHP yield and purity, especially more favorable with flavorzyme, neutrase, alcalase, and pepsin. Furthermore, the polysaccharide fraction, which was obtained by ultrasonic pretreatment and then alcalase hydrolysis at the conditions of 3000 U/g, 55°C, pH 8.0, for 4 hr, exhibited an obvious scavenging effect on 2,2-diphenyl-1-picrylhydrazyl (DPPH) and hydroxyl radical (98.48 ± 0.55% and 99.20 ± 0.12%, respectively) and a lenoleic acid peroxidation inhibition effect (85.48 ± 0.65%) at a concentration of 5.0 mg/mL. These results reveal the potential application of CHP in functional food and nutraceuticals.

Topics: Animals; Antioxidants; Benzothiazoles; Biotechnology; Biphenyl Compounds; Crassostrea; Free Radical Scavengers; Hydrolysis; Hydroxyl Radical; Linoleic Acid; Lipid Peroxidation; Models, Statistical; Picrates; Polysaccharides; Sulfonic Acids; Ultrasonics

Hemp seed protein hydrolysate (HPH) was produced through simulated gastrointestinal tract (GIT) digestion of hemp seed protein isolate followed by partial purification and separation into eight peptide fractions by reverse-phase (RP)-HPLC. The peptide fractions exhibited higher oxygen radical absorbance capacity as well as scavenging of 2,2-diphenyl-1-picrylhydrazyl, superoxide and hydroxyl radicals when compared to HPH. Radical scavenging activities of the fractionated peptides increased as content of hydrophobic amino acids or elution time was increased, with the exception of hydroxyl radical scavenging that showed decreased trend. Glutathione (GSH), HPH and the RP-HPLC peptide fractions possessed low ferric ion reducing ability but all had strong (>60 %) metal chelating activities. Inhibition of linoleic acid oxidation by some of the HPH peptide fractions was higher at 1 mg/ml when compared to that observed at 0.1 mg/ml peptide concentration. Peptide separation resulted in higher concentration of some hydrophobic amino acids (especially proline, leucine and isoleucine) in the fractions (mainly F5 and F8) when compared to HPH. The elution time-dependent increased concentrations of the hydrophobic amino acids coupled with decreased levels of positively charged amino acids may have been responsible for the significantly higher (p < 0.05) antioxidant properties observed for some of the peptide fractions when compared to the unfractionated HPH. In conclusion, the antioxidant activity of HPH after simulated GIT digestion is mainly influenced by the amino acid composition of some of its peptides.

Topics: Amino Acids; Antioxidants; Biphenyl Compounds; Cannabis; Chelating Agents; Chromatography, High Pressure Liquid; Diet; Dietary Proteins; Digestion; Ferric Compounds; Gastrointestinal Tract; Glutathione; Humans; Hydroxyl Radical; Linoleic Acid; Lipid Peroxidation; Peptides; Picrates; Plant Proteins; Protein Hydrolysates; Seeds; Superoxides

A traditional sweet dessert wine from Saracena (Italy), made with nonmacerated local white grapes (Guarnaccia, Malvasia and Moscato), was analyzed for phenolics and aroma profile and antioxidant activities. The most abundant classes of phenols identified by high-performance liquid chromatography were hydroxybenzoic acids and flavan-3-ols, where gallic acid showed the highest content (376.5 mg/L). The analysis by solid phase microextraction-gas chromatography-mass spectrometry revealed the presence of superior alcohols (from iso-butanol and iso-amyl alcohol up to 2-phenylethanol) and their ethyl esters, terpenes (such as linalool), furfuryl compounds, and free fatty acids (up to palmitic acid) as the key odorants of this wine. The antioxidant activity, evaluated by different in vitro assays 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS), and β-carotene bleaching test), showed that passito wine had a radical scavenging activity (IC50 value of 0.03 v/v against DPPH·) and inhibited linoleic acid oxidation with an IC50 value of 0.4 v/v after 30 min of incubation.

Topics: Antioxidants; Benzothiazoles; beta Carotene; Biphenyl Compounds; Chemical Phenomena; Chromatography, High Pressure Liquid; Gallic Acid; Gas Chromatography-Mass Spectrometry; Italy; Linoleic Acid; Odorants; Oxidation-Reduction; Phenylethyl Alcohol; Picrates; Polyphenols; Solid Phase Microextraction; Sulfonic Acids; Terpenes; Vitis; Wine

This study analyses the chemical composition and in vitro antioxidant activity of both the essential oil and the 80% aqueous acetone extract of Tetraclinis articulata leaves. The GC-MS analysis of the essential oil identified 66 components that comprise 93.5% of the oil. The major constituents of the oil are: bornyl acetate (31.4%), α-pinène (24.5%) and camphor (20.3%). Antioxidant activities of the samples were determined using four different test systems, namely DPPH, β-carotene/linoleic acid, reducing power and metal chelating activity assay. Test results from the DPPH system showed the strongest radical scavenging activity was exhibited by the 80% aqueous acetone extract (IC₅₀ = 5.5 µg mL⁻¹), which was two times higher than the positive control (BHT). The amount of the total phenolics, flavonoids and condensed tannins was very high in the 80% aqueous acetone extracts. The correlation between the antioxidant activity potential and total phenolic level of the extract was noted.

Topics: Antioxidants; beta Carotene; Biphenyl Compounds; Cupressaceae; Gas Chromatography-Mass Spectrometry; Linoleic Acid; Oils, Volatile; Picrates; Plant Extracts; Plant Leaves; Polyphenols

This study was carried out to appraise whether or not the exogenous application of a potential osmoprotectant, proline, could ameliorate the adverse effects of drought stress on maize seed and seed oil composition, as well as oil antioxidant activity. Water stress reduced the kernel sugar, oil, protein and moisture contents and most of the seed macro- and micro-elements analyzed in both maize cultivars but it increased the contents of seed fiber and ash. Water stress increased the oil oleic acid content with a subsequent decrease in the amount of linoleic acid, resulting in an increased oil oleic/linoleic ratio for both maize cultivars. However, no variation was observed in oil stearic and palmitic acids content due to water stress. A considerable drought induced an increase in seed oil α-, γ-, δ- and total tocopherols and flavonoids were observed in both maize cultivars. However, oil phenolic and carotenoid content as well as 1,1-diphenyl-2-picryl-hydrazyl (DPPH) free radical scavenging activity decreased. Foliar-applied proline significantly increased the content of seed sugar, oil, protein, moisture, fiber and ash in both maize cultivars under well irrigated and water deficit conditions. Furthermore, exogenous application of proline increased the oil oleic and linoleic acid contents. The concentrations of antioxidant compounds namely phenolics, carotenoids, flavonoids and tocopherols estimated in the seed oil increased due to foliar-applied proline under water deficit conditions that was positively correlated with the enhanced oil DPPH free radical scavenging activity. Moreover, the increase in the contents of these antioxidant compounds and oil antioxidant activity due to the foliar application of proline was noted to be more pronounced under water deficit conditions.

Topics: Antioxidants; Biphenyl Compounds; Carbohydrates; Carotenoids; Droughts; Linoleic Acid; Oleic Acid; Picrates; Plant Oils; Plant Proteins; Proline; Seeds; Species Specificity; Starch; Stress, Physiological; Tocopherols; Water; Zea mays

Defatted rice bran was treated with water, 50% (v/v) ethanol, ethanol, 50% (v/v) acetone, or acetone. The treatment temperature and time were fixed at 230°C and 5 min, respectively. The treatment with 50% (v/v) acetone produced the highest yield of 0.549 g-extract/g-bran, and the extract exhibited the highest DPPH radical scavenging activity of 0.495 mmol-ascorbic acid/g-extract. The extract obtained with 50% (v/v) acetone showed the higher UV absorbance and highest amount of hydrophobic substances in the HPLC analysis than the other extracts, and it also showed the highest antioxidative ability in both the rancidity test at 105°C and bulk oil system at 60°C for the longest induction period of 4.9 h and 14.4 h, respectively. However, the extracts obtained using various extractants showed no effect on the oxidation rate constant of linoleic acid in the bulk oil system.

Topics: Acetone; Antioxidants; Biphenyl Compounds; Chromatography, High Pressure Liquid; Ethanol; Free Radical Scavengers; Linoleic Acid; Oryza; Picrates; Plant Extracts; Solvents; Temperature; Time Factors; Water

A comparative evaluation of the antioxidant and acetylcholinesterase inhibitory activity of the leaf extracts of Croton gratissimus and Croton zambesicus (subgratissimus) and compounds isolated from the extracts was carried out to determine their potential and suitability or otherwise as a substitute for each other in the management of oxidative and neurodegenerative conditions. Different antioxidant assays (DPPH, FRAP, β-carotene-linoleic and the lipid peroxidation models) and the microplate assay for acetylcholinesterase (AChE) inhibition were carried out separately to study the activities of the crude leaf extracts and four solvent fractions from each of the two Croton species. Bioassay guided fractionation was used to target antioxidant constituents of the crude extracts and ethyl acetate fractions of 20% aqueous methanol extract of C. gratissimus on silica gel and Sephadex LH-20 columns resulted in the isolation of kaempferol-3-O-β-6''(p-coumaroyl) glucopyranoside (tiliroside, 2), apigenin-6-C-glucoside (isovitexin, 3) and kampferol (4). The extract of C. zambesicus yielded quercetin-3-O-β-6''(p-coumaroyl) glucopyranoside-3'-methyl ether (helichrysoside- 3'-methyl ether, 1), kaempferol-3-O-β-6''(p-coumaroyl) glucopyranoside (tiliroside, 2) and apigenin-6-C-glucoside (isovitexin, 3). Three of the isolated compounds and their different combinations were also included in the bioassays. In all the assays performed, the antioxidant capacity and AChE inhibitory effects of C. zambesicus extracts were weaker than those of C. gratissimus. This suggests that C. gratissimus may not be substituted by C. zambesicus, despite the similarity in some of their constituents. Generally, the combinations made from the isolated compounds showed better activities in most of the assays compared to the individual isolated compounds. This suggests mechanisms such as synergism and/or additive effects to be taking place. This study established low, moderate and high antioxidant activities as well as AChE inhibitory effects by the crude extracts, fractions, compounds and compound combinations. This means some of the extracts, isolated compounds and compound combinations could be useful in the management of neurodegenerative conditions and serve as sources of natural neurodegenerative agents.

Topics: Antioxidants; beta Carotene; Biological Assay; Biological Products; Biphenyl Compounds; Cholinesterase Inhibitors; Croton; Free Radical Scavengers; Iron; Linoleic Acid; Lipid Peroxidation; Malondialdehyde; Models, Biological; Oxidation-Reduction; Phospholipids; Picrates; Plant Extracts; Plant Leaves; Thiobarbituric Acid Reactive Substances

Investigation of the green fruits of Clusia paralicola (Clusiaceae) led to the isolation and characterization of two 3,8"-biflavonoids, 2R, 3S, 2"R, 3"R-GB1-7"-O-beta-glucoside (1) and 2R, 3S, 2"R, 3,8"-binaringenin-7"-O-beta-glucoside (2), together with four known compounds: beta-sitosterol, stigmasterol, beta-amyrin, and epicatechin. The structures were established from the IR, LC-ESI-MS and NMR spectral data, including 2D-NMR experiments. The absolute configurations of 1 and 2 were determined by CD spectra. The total extract and the biflavonoids demonstrated significant antioxidant activity in DPPH, ABTS, and betacarotene/linoleic acid tests.

Topics: Antioxidants; Benzothiazoles; beta Carotene; Biphenyl Compounds; Circular Dichroism; Clusia; Flavanones; Flavonoids; Fruit; Linoleic Acid; Magnetic Resonance Spectroscopy; Picrates; Spectrometry, Mass, Electrospray Ionization; Spectrophotometry, Infrared; Spectrophotometry, Ultraviolet; Sulfonic Acids

This study was designed to investigate the antioxidant and antimicrobial activities of the essential oils from Piper officinarum C. DC. GC and GC/MS analysis of the leaf and stem oils showed forty one components, representing 85.6% and 93.0% of the oil, respectively. The most abundant components in the leaf oil were beta-caryophyllene (11.2%), alpha-pinene (9.3%), sabinene (7.6%), beta-selinene (5.3%) and limonene (4.6%), while beta-caryophyllene (10.9%), alpha-phellandrene (9.3%), linalool (6.9%), limonene (6.7%) and alpha-pinene (5.0%) were the main components of the stem oil. The antioxidant activities were determined by using complementary tests: namely beta-carotene-linoleic acid, DPPH radical scavenging and total phenolic assays. The stems oil showed weak activity (IC50 = 777.4 microg/mL) in the DPPH system, but showed moderate lipid peroxidation inhibition in the beta-carotene-linoleic acid system (88.9 +/- 0.35%) compared with BHT (95.5 +/- 0.30%). Both oils showed weak activity against P. aeruginosa and E. coli with M IC values of 250 microg/mL.

Topics: Anti-Infective Agents; Antioxidants; beta Carotene; Biphenyl Compounds; Escherichia coli; Free Radical Scavengers; Fungi; Gas Chromatography-Mass Spectrometry; Indicators and Reagents; Linoleic Acid; Lipid Peroxidation; Microbial Sensitivity Tests; Oils, Volatile; Phenols; Picrates; Piper; Plant Leaves; Plant Stems; Pseudomonas aeruginosa; Solvents

Ginkgo biloba seeds are widely used as a food and traditional medicine in China. In the present study, a novel antioxidant protein named GBSP was purified from Ginkgo biloba seeds. The protein (GBSP) was purified by homogenization of Ginkgo biloba seed powder in saline solution, 70% ammonium sulphate precipitation, filtration on a DEAE-Cellulose52 anion exchange column, gel filtration on a Sephadex G-50 column, and preparative chromatography on a C(18) column using RP-HPLC. GBSP showed an apparent molecular weight of 18 kDa by SDS-PAGE and MALDI-TOF/MS analyses. The amino acid sequence obtained by MALDI-TOF/TOF MS analysis showed GBSP was a novel protein, as no matching protein in was found the database. The protein exhibited significant antioxidant activities against free radicals such as DPPH, ABTS and superoxide anion and showed higher activity than α-tocopherol in a linoleic acid emulsion assay system. Furthermore, GBSP exhibited notable reducing power and a strong chelating effect on Cu(2+) and Fe(2+). Therefore, the present study demonstrates, for the first time, that this novel protein from Ginkgo biloba seeds is an excellent antioxidant.

Topics: alpha-Tocopherol; Antioxidants; Benzothiazoles; Biphenyl Compounds; China; Electrophoresis, Polyacrylamide Gel; Emulsions; Ginkgo biloba; Linoleic Acid; Lipid Peroxidation; Picrates; Plant Proteins; Seeds; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; Sulfonic Acids; Superoxides

Quaternary amino groups were introduced into chitin and chitosan to obtain O-(2-hydroxy-3-trimethylammonium)propyl chitin (OHT-chitin) and N-(2-hydroxy-3-trimethylammonium)propyl chitosan (NHT-chitosan). They were characterized by FTIR spectra, and GPC. The molecular weight Mw of OHT-chitin and NHT-chitosan were 8986 and 9723 with polydispersity of 1.01 and 1.0 2, respectively. Their antioxidant activities in vitro were further studied. It was found that β-carotene-linoleic acid values of OHT-chitin and NHT-chitosan at 0.8 mg/mL were up to 91% and 96%, while that of chitosan was 40%. Based on photobleaching of α,α-diphenyl-β-picrylhydrazyl (DPPH) at 326 nm, the DPPH inhibitory activity of OHT-chitin and NHT-chitosan was 30.9% and 31.9% at 5 mg/mL, whereas chitosan only gave 4.8%. It was also exhibited that OHT-chitin and NHT-chitosan had better antioxidant activity than chitosan according to the reducing power as well as H2O2 scavenging activity.

Topics: Antioxidants; beta Carotene; Biphenyl Compounds; Chitin; Chitosan; Hydrogen Peroxide; Linoleic Acid; Oxidants; Picrates

This study was designed to evaluate the in vitro antioxidant activities of n-hexane (Hex), dichloromethane (DCM), methanol (MeOH) and essential oils (EO) extracts obtained from Salvia euphratica var. euphratica and Salvia euphratica var. leiocalycina and to determine their essential oil and phenolic acid compositions. The samples were screened for their antioxidant activity by using DPPH and β-carotene/linoleic acid assays. Methanol extracts of both varieties exhibited strong antioxidant activities. Our results showed that rosmarinic acid was dominant phenolic acid of MeOH extracts (39.4 and 55.8 µg mg⁻¹, respectively). The chemical compositions of essential oils of two varieties were analysed and their main components were determined as eucalyptol (18.4%) and trans-pinocarvyl acetate (24.9%), respectively. It can be said that these varieties could be used as natural antioxidant.

Topics: Antioxidants; beta Carotene; Biphenyl Compounds; Chromatography, High Pressure Liquid; Cinnamates; Cyclohexanols; Depsides; Drug Evaluation, Preclinical; Eucalyptol; Free Radical Scavengers; Gas Chromatography-Mass Spectrometry; Hydroxybenzoates; Linoleic Acid; Methanol; Monoterpenes; Oils, Volatile; Picrates; Plant Extracts; Rosmarinic Acid; Salvia; Turkey

Hydroponic culture was used to investigate the effect of NaCl concentrations on the growth, nutrient uptake, phenolic content and antioxidant activity of Salvia officinalis L. leaves. The antioxidant capacity of the methanolic extract of S. officinalis was evaluated by using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging test and β-carotene-linoleic acid bleaching assay. Physiological and biochemical parameters of S. officinalis were assessed after 4 weeks of salt treatment with 0, 25, 50, 75 and 100 mmol L(-1) NaCl.. Plant growth exhibited a reduction of 61% at 100 mmol L(-1) NaCl. Assessment of Na(+), K(+) and Ca(2+) and water contents of shoots and roots showed that S. officinalis is able to regulate Na(+) concentration by active compartmentation in vacuoles. Salvia officinalis phenolics were increased in response to salinity at the threshold of 75 mmol L(-1) NaCl. This herb was also found to be able to achieve important DPPH(•) quenching activity and to inhibit the β-carotene-linoleic acid bleaching notably enhanced by salt treatment. It is interesting to highlight the correlation between the phenolic and antioxidant activity, suggesting the involvement of these compounds in this activity.. Salvia officinalis treated with 75 mmol L(-1) NaCl constitutes a potential source for production of secondary metabolites useful in several applications.

Topics: Antioxidants; beta Carotene; Biphenyl Compounds; Calcium; Hydroponics; Linoleic Acid; Phenols; Picrates; Plant Leaves; Plant Roots; Potassium; Salinity; Salt Tolerance; Salvia officinalis; Sodium; Sodium Chloride; Stress, Physiological; Vacuoles; Water

The present investigation was carried out to appraise the levels of total phenols and vitamin C as well as antioxidant potential at three different ripening stages (un-ripe, semi-ripe and fully-ripe) of guava (Psidium guajava L.) fruit collected from three different geographical regions of Pakistan (Islamabad, Faisalabad and Bhakkar). The antioxidant potential of guava fruit extracts was assessed by means of different in-vitro antioxidant assays, namely inhibition of peroxidation in linoleic acid system, reducing power and radical scavenging capability. Overall, fruit at the un-ripe stage (G1) exhibited the highest levels of TPC, TFC, reducing power and DPPH radical scavenging activity, followed by the semi-ripe (G2) and fully-ripe (G3) stages. On the other hand, vitamin C content increased as the fruit maturity progressed, with highest value seen at the fully-ripe stage (G3) followed by the semi-ripe (G2) and un-ripe stage (G1). The concentration of vitamin C in fruits varied as: Faisalabad (136.4-247.9 mg 100 g⁻¹), Islamabad (89.7-149.7 mg 100 g⁻¹) and Bhakkar (73.1-129.5 mg 100 g⁻¹). The results showed that different stages of maturation and geographical locations had profound effects on the antioxidant activity and vitamin C contents of guava fruit.

Topics: Ascorbic Acid; Biphenyl Compounds; Flavonoids; Free Radical Scavengers; Fruit; Linoleic Acid; Lipid Peroxidation; Pakistan; Phenols; Picrates; Plant Extracts; Psidium; Reducing Agents

In the present study, in vitro antioxidant, antioxidative stress and hepatoprotective activity of Moringa oleifera Lam. seed oil (Ben oil; BO) was evaluated against carbon tetrachloride (CCl(4) ) induced lipid peroxidation and hepatic damage in rats. The oil at 0.2 and 0.4 mL/rat was administered orally for 21 consecutive days. The substantially elevated serum enzymatic (GOT, GPT, ALP, GGT) and bilirubin levels were significantly restored towards normalization by the oil. There was a significant elevation in the level of malondialdehyde (MDA), non-protein sulfhydryl (NP-SH), and total protein (TP) contents in the liver tissue. The results obtained indicated that BO possesses potent hepatoprotective action against CCl(4) -induced hepatic damage by lowering liver marker enzymes, MDA concentration, and elevating NP-SH and TP levels in liver tissue. The biochemical observations were supplemented with histopathological examination of rat liver. The results of this study showed that treatment with Ben oil or silymarin (as a reference) appears to enhance the recovery from hepatic damage induced by CCl(4) . The pentobarbital induced narcolepsy prolongation in mice was retarded by the Ben oil. Acute toxicity test in mice showed no morbidity or mortality. In vitro DPPH radical scavenging and β-carotene-linolic acid assay tests of the BO exhibited a moderate antioxidant activity in both tests used. The possible mechanism(s) of the liver protective activity of Ben oil activity may be due to free radical scavenging potential caused by the presence of antioxidant component(s) in the oil. Consequently, BO can be used as a therapeutic regime in treatment of some hepatic disorders.

Topics: Animals; Antioxidants; beta Carotene; Bilirubin; Biphenyl Compounds; Carbon Tetrachloride Poisoning; Chemical and Drug Induced Liver Injury; Female; Linoleic Acid; Lipid Peroxidation; Liver; Male; Malondialdehyde; Mice; Moringa oleifera; Picrates; Plant Oils; Rats; Rats, Wistar; Seeds; Silymarin

Medicinal plants are possible sources for future novel antioxidant compounds in food and pharmaceutical formulations. Recent attention on medicinal plants emanates from their long historical utilisation in folk medicine as well as their prophylactic properties. However, there is a dearth of scientific data on the efficacy and stability of the bioactive chemical constituents in medicinal plants after prolonged storage. This is a frequent problem in African Traditional Medicine.. The phytochemical, antioxidant and acetylcholinesterase-inhibitory properties of 21 medicinal plants were evaluated after long-term storage of 12 or 16 years using standard in vitro methods in comparison to freshly harvested materials.. The total phenolic content of Artemisia afra, Clausena anisata, Cussonia spicata, Leonotis intermedia and Spirostachys africana were significantly higher in stored compared to fresh materials. The flavonoid content were also significantly higher in stored A. afra, C. anisata, C. spicata, L. intermedia, Olea europea and Tetradenia riparia materials. With the exception of Ekebergia capensis and L. intermedia, there were no significant differences between the antioxidant activities of stored and fresh plant materials as measured in the β-carotene-linoleic acid model system. Similarly, the EC50 values based on the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay were generally lower for stored than fresh material. Percentage inhibition of acetylcholinesterase was generally similar for both stored and fresh plant material. Stored plant material of Tetradenia riparia and Trichilia dregeana exhibited significantly higher AChE inhibition than the fresh material.. The current study presents evidence that medicinal plants can retain their biological activity after prolonged storage under dark conditions at room temperature. The high antioxidant activities of stable bioactive compounds in these medicinal plants offer interesting prospects for the identification of novel principles for application in food and pharmaceutical formulations.

Topics: Acetylcholinesterase; Antioxidants; beta Carotene; Biphenyl Compounds; Cholinesterase Inhibitors; Drug Stability; Drug Storage; Flavonoids; Linoleic Acid; Magnoliopsida; Phenols; Picrates; Plant Extracts; Plants, Medicinal

Bioactive polyphenols, cartenoids, and anthocyanins present in fruits and vegetables are receiving much attention because of their potential antioxidant activity. This study was conducted to determine antioxidant activity of leaves, peels, stem bark, and kernel of mango varieties langra and chonsa. Total phenolic (TPC) and total flavonoid contents (TFCs) in segments of langra ranged from 63.89 to 116.80 mg GAE/g DW and 45.56 to 90.89 mg CE/g DW, respectively, and that of chonsa were 69.24 to 122.60 mg GAE/g DW and 48.43 to 92.55 mg CE/g DW, respectively. The 2, 2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity and linoleic inhibition capacity in segments of langra ranged from 53.30% to 61.10% and 40.0% to 47.20%, respectively, whereas for chonsa; 56.40% to 66.0% and 48.1% to 49.0%, respectively. The reducing potentials of different segments of langra and chonsa at concentration of 10 mg/mL were 0.512 to 0.850 and 0.595 to 0.665 mV, respectively. Comparison between both varieties showed chonsa exhibited better antioxidant activity. Data were analyzed by analysis of variance (ANOVA) using completely randomised design (CRD) under factorial.

Topics: Antioxidants; Biphenyl Compounds; Flavonoids; Fruit; Linoleic Acid; Mangifera; Pakistan; Picrates; Plant Bark; Plant Extracts; Plant Leaves; Plant Stems; Polyphenols

Defatted rice bran extracts were obtained by subcritical treatment using aqueous acetone as extractant. Treatment with 40% (v/v) acetone at 230 °C for 5 min yielded an extract with the highest 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity (0.274 mmol of ascorbic acid/g of bran), total carbohydrate (0.188 g/g of bran), protein (0.512 g/g of bran), and total phenolic contents (88.2 mg of gallic acid/g of bran). The effect of treatment temperature (70-230 °C) was investigated using 40% (v/v) acetone, and the extract under 230 °C treatment showed the highest levels of all the determinations described above. The extracts obtained with various concentrations of aqueous acetone were subjected to UV absorption spectra and HPLC analysis, and the results showed changes in composition and polarity. Antioxidative activity evaluated against oxidation of bulk linoleic acid of the extract obtained with 80% (v/v) acetone was higher than that not only of the extract from subcritical water treatment but also of that obtained 40% (v/v) acetone treatment.

Topics: Acetone; Ascorbic Acid; Biphenyl Compounds; Chromatography, High Pressure Liquid; Fatty Acids; Free Radical Scavengers; Gallic Acid; Hot Temperature; Linoleic Acid; Liquid-Liquid Extraction; Oryza; Picrates; Plant Extracts; Solvents; Water

The purpose of this study was to evaluate the antioxidative activities of water and 70% ethanolic extracts from the Thymus quinquecostatus Celak (TQC) for natural antioxidant source. The antioxidant activities were compared with other natural and synthetic antioxidants. The levels of total polyphenols and flavonoids were also determined. The extracts were found to have different levels of antioxidant properties in a few kind of assay. The results showed that higher radical scavenging activity, reducing power and antioxidant capacity in FRAP than those of BHT as a positive control. In addition, the extracts from the TQC leaf and stem showed stronger antioxidant activity than that of vitamin C, α-tocopherol in ferric thiocyanate (FTC) and thiobarbituric acid (TBA) methods. Cytoprotective and anti-apoptotic effect of water extracts from TQC was also prevented t-BHP-induced toxicity in Chang liver cells. Therefore, these results indicate that TQC extracts have antioxidant properties through its ability to enhance the cell viability, reduction of production of ROS, inhibition of oxidative damage, mitochondria dysfunction and ultimately inhibition of cell apoptosis. Based on the results described above, it is suggested that TQC has the potential to protect liver on t-BHP-induced cell damage and should be considered as a prospective functional food.

Topics: alpha-Tocopherol; Antioxidants; Apoptosis; Benzothiazoles; Biphenyl Compounds; Cell Cycle; Cells, Cultured; Drug Evaluation, Preclinical; Flavonoids; Free Radical Scavengers; Humans; Iron; Linoleic Acid; Lipid Peroxidation; Membrane Potential, Mitochondrial; Picrates; Plant Extracts; Plant Leaves; Polyphenols; Reactive Oxygen Species; Sulfonic Acids; tert-Butylhydroperoxide; Thiazoles; Thiocyanates; Thymus Plant

Two novel peptides, ECH (Glu-Cys-His) and YECG (Tyr-Glu-Cys-Gly), were designed based on glutathione (Glu-Cys-Gly, GSH) and their antioxidant activities were studied. Various chemical methods based on single-electron-transfer (SET) and hydrogen-atom-transfer (HAT) were applied to evaluate the antioxidant activities of the peptides. For SET-based assay, tripeptide ECH displayed the highest DPPH radical scavenging activity (80.16%) and the strongest reducing power (A(700)=0.378). Besides, ECH also exhibited the best inhibition activity toward linoleic acid peroxidation with inhibition rate 98.25% at 7th day, which is a HAT-based assay. However, for another two HAT-based assays, it was tetrapeptide YECG that showed extraordinary oxygen radical absorption capacity (ORAC value=2.42 μM Trolox/μM) and ABTS free radical scavenging ability (8.88 mM Trolox/mM). In vitro cultured PC12 cell model also suggested that YECG gave the best protection for PC12 cells to resist H(2)O(2)-treated necrosis. It was found that the discrepancy of antioxidant capacity between ECH and YECG was caused by the presence of antioxidant amino acids (His/Tyr) and their position in peptide chain. With His located at C-terminal position, ECH demonstrated good electrons donating capacity, while with Tyr at N-terminal position, YECG exhibited strong oxygen radical absorbance capacity.

Topics: Animals; Antioxidants; Biphenyl Compounds; Free Radical Scavengers; Glutathione; Hydrogen; Hydrogen Peroxide; Linoleic Acid; Oxidation-Reduction; PC12 Cells; Peptides; Picrates; Rats; Structure-Activity Relationship

This study was undertaken to determine the chemical composition and antioxidative capacity of Echinophora platyloba DC. essential oil, and its antimicrobial potency against Listeria monocytogenes, Bacillus cereus, Bacillus subtilis, Staphylococcus aureus, Salmonella typhimurium, Escherichia coli O157:H7, Pseudomonas aeruginosa, Candida albicans, Candida tropicalis, Rhodotorula rubra, and Rhodotorula mucilaginosa. The essential oil was analyzed by GC and GC-MS; and evaluated for its antioxidative and antimicrobial (singly or in combination with chitosan, nisin, monolaurin, or amphotericin B) activity. Thirty-three components were characterized representing 95.69% of the total oil composition in which thymol, trans-ocimene, carvacrol, and (E)-sesqui-lavandulol were the major constituents. The oil exhibited high scavenging (IC(50): 49.7 ± 2.3 μg/mL) and relative antioxidative activity (RAA%: 85.21 ± 0.4) in 1,1-diphenyl-2-picrylhydrazyl radicals and β-carotene/linoleic acid bleaching assays, respectively. The oil showed antimicrobial activity against L. monocytogenes, B. cereus, B. subtilis, S. aureus, S. typhimurium, E. coli O157:H7, P. aeruginosa, C. albicans, C. tropicalis, R. Rubra, and R. mucilaginosa. Moreover, R. mucilaginosa and P. aeruginosa were the most susceptible and most resistant organisms, respectively. Regarding the checkerboard data, 47 fractional inhibitory concentration index (FICIs) (≤ 0.5) indicated synergistic, whereas 7 FICIs (>0.5 to 1) indicated additive effect. Consequently, E. platyloba DC. essential oil could be used as a recommended natural antioxidant and antimicrobial substance for food preservation.

Topics: Acyclic Monoterpenes; Amphotericin B; Anti-Infective Agents; Antioxidants; Apiaceae; beta Carotene; Biphenyl Compounds; Chitosan; Cymenes; Drug Interactions; Drug Resistance, Multiple, Bacterial; Food Contamination; Food Microbiology; Gas Chromatography-Mass Spectrometry; Gram-Negative Bacteria; Gram-Positive Bacteria; Laurates; Linoleic Acid; Microbial Sensitivity Tests; Monoglycerides; Monoterpenes; Nisin; Oils, Volatile; Picrates; Plant Oils; Thymol

Cinnamoylphenethylamine (CNPA) derivatives including feruloylphenethylamine (FRPA), caffeoylphenethylamine (CFPA), cinnamoyltyramine (CNTA), feruloyltyramine (FRTA) and caffeoyltyramine (CFTA) were synthesized in order to investigate the influence of the number and position of hydroxyl group on Cu(2+)/glutathione (GSH) and 2,2'-azobis(2-amidinopropane hydrochloride) (AAPH)-induced oxidation of DNA. The radical-scavenging properties of these CNPA derivatives were also evaluated by trapping 2,2'-azinobis(3-ethylbenzothiazoline-6-sulphonate) cationic radical (ABTS(+•)), 2,2'-diphenyl-1-picrylhydrazyl radical (DPPH) and galvinoxyl radical. In addition, these CNPA derivatives were tested by linoleic acid (LH)-β-carotene-bleaching experiment. The chemical kinetic was employed to treat the results from AAPH-induced oxidation of DNA and gave the order of antioxidant ability as CFTA > CFPA > FRTA > FRPA. CFTA and CFPA also possessed high abilities to inhibit Cu²(+)/GSH-mediated degradation of DNA, whereas FRPA and FRTA can protect LH against the auto-oxidation efficiently. Finally, CFPA and FRPA exhibited high activity in trapping ABTS(+•), DPPH and galvinoxyl radicals. Therefore, the cinnamoyl group bearing ortho-dihydroxyl or hydroxyl with ortho-methoxyl benefited for CNPA derivatives to protect DNA, while hydroxyl in tyramine cannot enhance the radical-scavenging abilities of CNPA derivatives.

Topics: Amidines; Antioxidants; Benzhydryl Compounds; Benzothiazoles; beta Carotene; Biphenyl Compounds; Cinnamates; Copper; DNA; Free Radical Scavengers; Glutathione; Hydroxides; Linoleic Acid; Oxidation-Reduction; Phenethylamines; Picrates; Solutions; Structure-Activity Relationship; Sulfonic Acids

Some fused dihydrooxepino[f]-, [g]-, and [h]coumarins were obtained from the ring-closing metathesis of the corresponding o-allyl-allyloxycoumarins under the treatment with the first generation Grubbs' catalyst. These compounds were tested in vitro for their antioxidant activity, and they present significant scavenging activity. They were also showed to inhibit in vitro soybean lipoxygenase.

Topics: Biphenyl Compounds; Coumarins; Enzyme Inhibitors; Free Radical Scavengers; Glycine max; Hydroxyl Radical; Linoleic Acid; Lipid Peroxidation; Lipoxygenase; Molecular Structure; Picrates; Structure-Activity Relationship

The metal chelating activity, antioxidant properties, and the effect on carbohydrate-hydrolyzing enzymes of Ethiopian spice blend Berbere have been investigated. Berbere contains a total amount of phenols corresponding to 71.3 mg chlorogenic acid equivalent per gram of extract and a total flavonoid content of 32.5 mg quercetin equivalent per gram of extract. An increase of the resistance towards forced oxidation was obtained when Berbere was added to sunflower oil. In order to evaluate the bioactivity of the non-polar constituents, an n-hexane extract was obtained from Berbere. The gas chromatography-mass spectrometry analysis revealed the presence of 19 fatty acids constituents (98.1% of the total oil content). Among them, linoleic acid was the major component (72.0% of the total lipids). The ethanolic extract had the highest ferric-reducing ability power (35.4 μM Fe(II)/g) and DPPH scavenging activity with a concentration giving 50% inhibition (IC(50)) value of 34.8 μg/ml. Moreover, this extract exhibited good hypoglycemic activity against α-amylase (IC(50) = 78.3 μg/ml). In conclusion, Ethiopian spice blend Berbere showed promising antioxidant and hypoglycemic activity via the inhibition of carbohydrate digestive enzymes. These activities may be of interest from functional point of view and for the revalorization of the spice blend in gastronomy also outside the African country.

Topics: alpha-Amylases; Antioxidants; Biphenyl Compounds; Chelating Agents; Enzyme Inhibitors; Ethiopia; Fatty Acids; Ferric Compounds; Gas Chromatography-Mass Spectrometry; Hypoglycemic Agents; Inhibitory Concentration 50; Linoleic Acid; Oxidation-Reduction; Picrates; Plant Extracts; Plant Oils; Polyphenols; Spices; Sunflower Oil

Reactive oxygen species, along with reactive nitrogen species, may play an important role in the pathogenesis and progress of many diseases, including cancer, diabetes and sickle cell disease. It has been postulated that hydroxyurea, one of the main treatments in sickle cell disease, achieves its activity partly also through its antioxidant properties. A series of hydroxyurea derivatives of L- and D-amino acid amides and cycloalkyl-N-aryl-hydroxamic acids was synthesized and investigated for their radical scavenging activity, chelating properties and antioxidant activity. All the compounds showed exceptional antiradical activities. For example, free radical scavenging activities of investigated hydroxyureas were higher than the activity of standard antioxidant, butylated hydroxyanisole (BHA). Moreover, most of the investigated hydroxamic acids were stronger Fe²⁺ ion chelators than quercetin. In addition, the investigated compounds, especially hydroxamic acids, were proven to be excellent antioxidants. They were as effective as BHA in inhibiting β-carotene-linoleic acid coupled oxidation. It is reasonable to assume that the antioxidant activity of the investigated compounds could contribute to their previously proven biological properties as cytostatic and antiviral agents.

Topics: Anemia, Sickle Cell; beta Carotene; Biphenyl Compounds; Butylated Hydroxyanisole; Butylated Hydroxytoluene; Free Radical Scavengers; Humans; Hydroxamic Acids; Hydroxyurea; Iron; Iron Chelating Agents; Linoleic Acid; Magnetic Resonance Spectroscopy; Neoplasms; Oxidation-Reduction; Picrates; Reactive Oxygen Species; Spectrophotometry, Infrared

The present study was conducted to determine whether aerial parts of Trichosanthes cucumerina extracts can exert significant antioxidant activity. The antioxidant activity of a hot water extract (HWE) and a cold ethanolic extract (CE) of T. cucumerina aerial parts was evaluated by assessing its (a) radical scavenging ability and prevention effect of lipid peroxidation in vitro, and (b) effects on lipid peroxidation and antioxidant enzyme activities, in vivo.In vitro antioxidant assays (DPPH, TBARS and carotene-linoleic acid assays) clearly demonstrated the antioxidant potential of HWE and CEE. Moreover, HWE increased SOD: by 91.2% and GPX by 104.4% while CEE increased SOD: by 115.5% and GPX by 96.4%) in CCl4-induced rats. Treatments with HWE and CE prevented the accumulation of lipid peroxidation products by 30.5% and 33.8%, respectively, in liver tissues compared to the rats exposed only to CCl4. In conclusion, the present investigation demonstrates for the first time that components in T. cucumerina aerial parts can exert significant antioxidant activity in vivo and in vitro.

Topics: Animals; Antioxidants; Biphenyl Compounds; Cold Temperature; Dose-Response Relationship, Drug; Ethanol; Female; Glutathione Peroxidase; In Vitro Techniques; Linoleic Acid; Lipid Peroxidation; Male; Picrates; Rats; Superoxide Dismutase; Thiobarbituric Acid Reactive Substances; Trichosanthes

The present study was performed to evaluate the in vitro antimicrobial and antioxidant properties of various extracts of Verbascum (V.) pinetorum, a member of Scrophulariaceae family. While the antimicrobial activity of various extracts of V. pinetorum was determined with agar-well diffusion method, the antioxidant activity was examined with two complementary test systems, namely 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging and beta-carotene/linoleic acid test systems.. The hexane extract exhibits antimicrobial activity against few microorganisms. However, dichloromethane, direct methanol and methanol/chloroform extracts are effective on a broad range of microorganisms. Among the tested bacteria Haemophilus influenzae was found to be the most sensitive bacterium. The 50% (IC50) inhibition activity of the methanolic extract of V. pinetorum on the free radical DPPH was determined as 13.04 mg/ml. In the case of the linoleic acid system, oxidation of linoleic acid was inhibited by methanolic extract of V. pinetorum, which showed 89.39% inhibition that is quite close to the value of the synthetic antioxidant reagent butylhydroxytoluene (BHT), 92.46%. Iridoid glycosides, flavonoids and saponins were determined as the major natural compounds in the methanolic extracts. The total phenolic components of V. pinetorum were found as 42.45 mg/g gallic acid equivalent.. The results provide evidence that the extracts of V. pinetorum contained iridoid glycosides, flavonoids, saponins and phenolic compounds which may be responsible for the substantial antimicrobial and antioxidant activities.

Topics: Animals; Anti-Infective Agents; Antioxidants; beta Carotene; Biphenyl Compounds; Hexanes; In Vitro Techniques; Linoleic Acid; Methanol; Methylene Chloride; Microbial Sensitivity Tests; Phenols; Picrates; Plant Extracts; Verbascum

Centaurea species are used for the treatment of various ailments in the popular medicine in some countries. This study was designed to examine antioxidant potentials and fatty acid profiles of five Centaurea species from Turkey flora. Antioxidant properties of methanolic extracts from these species were evaluated by six different methods: phosphomolybdenum assay, free radical scavenging assay, β-carotene/linoleic acid test system, metal chelating activity, ferric and cupric reducing power. Total phenolic and flavonoid concentrations of each extract were also determined using the Folin-Ciocalteu reagent and aluminum chloride. The results of these assay showed a significant antioxidant capacity in all researched extracts. Centaurea cheirolopha extract, with the highest amount of total phenolic and flavonoids, showed the highest antioxidant activities in all assay, except for metal chelating. Fatty acid profiles of these species were examined by GC-FID and 30 fatty acids were identified. Palmitic, linoleic, oleic, and linolenic acid were detected as the main components. The results of the study indicated that the Centaurea species can be considered as a source of new natural antioxidants and unsaturated fatty acids for food, cosmetic and pharmaceutical industries.

Topics: Animals; Antioxidants; beta Carotene; Biphenyl Compounds; Centaurea; Chelating Agents; Fatty Acids; Flavones; Free Radicals; Linoleic Acid; Metals; Phenols; Picrates; Plant Oils; Species Specificity; Turkey

The major phytochemicals and antioxidant properties of taro-scented rice bran (TaiNung 71; TN71) extracts using 3 different solvents are characterized. Some progress is realized in creating an economic value for rice bran that has long been considered an agricultural waste. Various solvent extracts reveal the presence of phenolic compounds, oryzanols, tocopherols, and tocotrienols. Ethyl acetate (EtOAc) can extract more oryzanols (1.55 ± 0.20 g/kg rice bran). Meanwhile, the methanol (MeOH) extract possesses a higher yield in total contents (15.42 ± 1.41 g/kg bran), which includes phenolic compounds (2.69 ± 0.29 g gallic acid equivalent/kg bran), tocopherols (251 ± 26 mg/kg bran) and tocotrienols (111 ± 4 mg/kg bran). The MeOH extract exhibits more effective antioxidant activity against various oxidative systems in vitro, including the inhibition of linoleic acid peroxidation (33.89%), scavenging of DPPH radicals (83.88%), and reducing power. It is found that the yield, total content in phenolic compounds and tocols of the extracts increase with increasing Synder's polarity value and viscosity, which can then be used as the indices in isolation of the desired rice bran phytochemicals extracts.

Topics: Antioxidants; Biphenyl Compounds; Colocasia; Linoleic Acid; Oryza; Oxidation-Reduction; Phenols; Phenylpropionates; Picrates; Plant Extracts; Solvents; Tocopherols; Tocotrienols

This study is outlined to probe the chemical composition of essential oil and in vitro antioxidant activity of the essential oil and methanol extracts of Psammogeton canescens. The chemical composition of the hydrodistilled essential oil of the aerial parts of P. canescens was analyzed by GC and GC/MS. The main constituents of the oil were found to be beta-bisabolene (33.35%), apiole (28.34%), alpha-pinene (11.86%) and dill apiole (8.17%). Antioxidant activities of the samples were determined by three various testing systems namely DPPH, beta-carotene/linoleic acid, and reducing power assay. In DPPH system, the highest radical-scavenging activity was seen by the polar subfraction of methanol extract (49.5+/-1.21mug/ml). Furthermore, in the second case the inhibition capacity (%) of the polar subfraction (92.40%+/-0.72) found to be the stronger one. However, in the reducing power assay, a reverse activity pattern more than in the first two systems was observed, and the essential oil was stronger radical reducer than was the methanol extract in all of the concentration tested. Our findings demonstrate that the essential oil and methanol extracts of P. canescens possess significant antioxidant activities and may be suggested as a new potential source of natural antioxidant.

Topics: Antioxidants; Apiaceae; beta Carotene; Biphenyl Compounds; Free Radical Scavengers; Indicators and Reagents; Linoleic Acid; Methanol; Oils, Volatile; Oxidation-Reduction; Phenols; Picrates; Plant Extracts; Solvents

The leaf essential oils from seven Himalayan Lauraceae species viz. Neolitsea pallens, Lindera pulcherrima, Dodecadenia grandiflora, Persea duthiei, Persea odoratissima, Persea gamblei and Phoebe lanceolata exhibited potent antioxidant and antibacterial activities. The in vitro antioxidant activity was assessed by using beta-carotene bleaching assay, reducing power, DPPH radical scavenging and inhibition of lipid peroxidation methods. The oils of D. grandiflora and L. pulcherrima showed a potent free radical scavenging activity as evidenced by low IC(50) value for DPPH radical (0.032 mg/ml and 0.087 mg/ml, respectively) and inhibition of lipid peroxidation (in between IC(50)=0.44 mg/ml and IC(50)=0.74 mg/ml, respectively). The oils were tested against three Gram negative (Escherichia coli, Salmonella enterica enterica and Pasturella multocida) and one Gram positive (Staphylococcus aureus) bacteria at different concentrations using disc diffusion and tube dilution methods. The inhibition zones (IZ) and MIC values for bacterial strains were in the range of 8.7-22.0mm and 3.90-31.25 microl/ml, respectively.

Topics: Anti-Bacterial Agents; Antioxidants; Bacteria; beta Carotene; Biphenyl Compounds; India; Indicators and Reagents; Lauraceae; Linoleic Acid; Lipid Peroxidation; Microbial Sensitivity Tests; Oils, Volatile; Oxidation-Reduction; Picrates

In this study, antioxidant and free radical scavenging activities of an endemic Salvia species (Salvia brachyantha (Bordz) probed. was assessed in vitro using 1,1-diphenyl-2-picryhydrazyl (DPPH) radical, beta-carotene linoleic acid, superoxide anion radical, hydroxyl radical, and reducing power assays. Regarding our data, the plant extract exhibited antioxidant and radical scavenging activities at different magnitudes of potency. In addition, this study was undertaken to assess whether methanol extract of S. brachyantha could increase the endogenous antioxidant enzymes in cells, and where such increased cellular defences could provide protection against oxidative cell injury. Pre treatment of rat heart cell lines with 100 microg/ml of plant extract for 24h significantly prevented cell damage and enhanced activity of antioxidant enzymes induced by a treatment with xanthine/xanthine oxidase. Increased reactive oxygen species and cell apoptosis induced by xanthine/xanthine oxidase was dose-dependently prevented when cells were pre treated for 24h with plant extract. These results indicated that S. brachyantha could protect against cell injury via induction of the antioxidant enzyme defences. The extract of this plant might be valuable antioxidant natural sources and seemed to be applicable in both healthy medicine and food industry.

Topics: Animals; Antioxidants; Biphenyl Compounds; Cell Line; Chromatography, High Pressure Liquid; Flavonoids; Free Radical Scavengers; Hydrogen Peroxide; Iran; Linoleic Acid; Myocytes, Cardiac; Oxidants; Oxidative Stress; Phenol; Picrates; Protective Agents; Rats; Reactive Oxygen Species; Reducing Agents; Salvia; Superoxides; Xanthine Oxidase

This study is designed for the determination of metal concentrations, antioxidant activity potentials and total phenolics of Amanita caesarea, Clitocybe geotropa and Leucoagaricus pudicus. Concentrations of four heavy metals (Pb, Cd, Cr, Ni) and five minor elements (Zn, Fe, Mn, Cu, Co) are determined. In the case of A. caesarea, Cr and Ni concentrations are found in a high level. Concentrations of the metals are found to be within safe limits for C. geotropa. In beta-carotene/linoleic acid test, L. pudicus showed the highest activity potential. In DPPH system, A. caesarea showed 79.4% scavenging ability. Additionally, reducing power and chelating capacity of the mushrooms increased with concentration. The strongest super-oxide anion scavenger was A. caesarea. In the case of total phenolics, L. pudicus found to have the highest content.

Topics: Agaricales; beta Carotene; Biphenyl Compounds; Chelating Agents; Environmental Monitoring; Food Contamination; Free Radical Scavengers; Indicators and Reagents; Linoleic Acid; Lipid Peroxidation; Metals, Heavy; Phenols; Picrates; Plant Extracts; Turkey

Series of imino and amino derivatives of 4-hydroxy coumarins were synthesized via conventional and microwave promoted procedure and evaluated for antioxidant potential through different in vitro models such as (DPPH) free radical scavenging activity, linoleic acid emulsion model system, reducing power assay and phosphomolybdenum method. All prepared compounds possess good antioxidant activity and among them p-nitro-phenyl derivative 6c with IC50 at 25.9 microM possesses radical scavenging activity which is comparable to standard BHT, while the best reducing power was observed in a case of benzyl amino compound 8c (RP50 255.6 microM). Also, observed data indicated that compounds may serve as inhibitors of lipid peroxidation process.

Topics: 4-Hydroxycoumarins; Amines; Antioxidants; Biphenyl Compounds; Catalysis; Emulsions; Free Radical Scavengers; Imines; Indicators and Reagents; Linoleic Acid; Lipid Peroxidation; Magnetic Resonance Spectroscopy; Microwaves; Oxidation-Reduction; Picrates

The aim of the present study was to evaluate antioxidative activities of the essential oil, methanol and water extracts of Iranian pennyroyal in vegetable oil during storage. Different concentrations (0, 200, 400, 600, 800 and 1000 ppm) of essential oil, water and methanol extracts and beta-hydroxy toluene (BHT; 200 ppm) were added to sunflower oil emulsion in the presence of cupric ions and incubated for 7 days at 60 degrees C. Peroxide values (PVs) and thiobarbituric acid reacting substances (TBARS) levels were measured in each day up to day of seven. Furthermore, antioxidant capacity of the essential oil and extracts were determined using DPPH and beta-carotene-linoleic acid methods. Values were compared among groups in each incubation time points using ANOVA. Results showed that DPPH and beta-carotene-linoleic acid assay findings on the Mentha pulegium extracts were comparable to those found on BHT. Furthermore, in all incubation time points, M. pulegium extracts lowered PVs and TBARS levels when compared to the control (p<0.001). In this respect, water extract was more potent than the methanol extract. Essential oil did not show considerable antioxidative effect. It seems that water extract of M. pulegium is a potent antioxidant which makes it as a potential antioxidant for oil and oily products during storage.

Topics: Antioxidants; beta Carotene; Biphenyl Compounds; Chromatography, Thin Layer; Free Radical Scavengers; Indicators and Reagents; Iran; Linoleic Acid; Lipid Peroxidation; Mentha; Oils, Volatile; Picrates; Plant Extracts; Plant Oils; Sunflower Oil; Thiobarbituric Acid Reactive Substances

This study is designed to examine the chemical composition and in vitro antioxidant activity of the hydrodistillated essential oil and various extracts obtained from Thymus longicaulis subsp. longicaulis var. longicaulis. GC and GC-MS analysis of the essential oil were resulted in determination 22 different compounds, representing 99.61% of total oil. gamma-terpinene, thymol and p-cymene were determined as the major compounds of the oil (27.80, 27.65 and 19.38%, respectively). Antioxidant activities of the samples were determined by four different test systems namely beta-carotene/linoleic acid, DPPH, reducing power and chelating effect. Essential oil showed the highest antioxidant activity in beta-carotene/linoleic acid system among the experiments examined. In the case of other test systems, in general, methanol and water extracts exhibited the strongest activity profiles. Especially, reducing power of water extract was found superior than those of synthetic antioxidants. As well as the antioxidant activities of the extracts, they were evaluated in terms of their total phenolic and flavonoid contents. Hexane and water extracts were found to be rich-in phenolics. However, flavonoids were determined in the highest level in methanol extract.

Topics: Antioxidants; beta Carotene; Biphenyl Compounds; Chromatography, Gas; Flavonoids; Gas Chromatography-Mass Spectrometry; Iron Chelating Agents; Linoleic Acid; Oils, Volatile; Oxidants; Picrates; Plant Extracts; Thymus Plant

In this work we report the isolation and characterisation of seven flavonoids, the levels of total phenolics, flavonoids and proanthocyanidins, and the antioxidant activity of the leaf extract of Rosa agrestis Savi (Rosaceae). The results showed that the R. agrestis leaf extract exhibited significant antioxidative activity as measured by 2,2-diphenyl-1-picrylhydrazyl (DPPH) (EC(50) = 47.4 microg mL(-1)), inhibited both beta-carotene bleaching and deoxyribose degradation, quenched a chemically generated superoxide anion in vitro and showed high ferrous ion chelating activity. Reactivity towards 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt (ABTS) radical cation and ferric-reducing antioxidant power (FRAP) values were equivalent to 2.30 mM L(-1) Trolox, the water soluble alpha-tocopherol analogue, and 1.91 mM L(-1) Fe(2+), respectively. The high antioxidant activity of the extract appeared to be attributed to its high content of total phenolics, flavonoids and proanthocyanidins. The flavonoids isolated from R. agrestis leaves were diosmetin, kaempherol, quercetin, kaempherol 3-glucoside (astragalin), quercetin 3-rhamnoside (quercitrin), quercetin 3-xyloside and quercetin 3-galactoside (hyperoside). Diosmetin (5,7,3'-trihydroxy-4'-methoxyflavone) was isolated for the first time from Rosa species.

Topics: beta Carotene; Biphenyl Compounds; Ferric Compounds; Flavonoids; Free Radical Scavengers; Hydroxyl Radical; Iron Chelating Agents; Linoleic Acid; Phenols; Picrates; Plant Leaves; Proanthocyanidins; Rosa; Superoxides

The major components of the essential oil of Piper divaricatum from Marajó Island, PA, Brazil, were methyleugenol (63.8%) and eugenol (23.6%), which were identified by GC and GC-MS. Essential oils of Piper species from the Brazilian Amazon are rich in either mono- and sesquiterpenes or phenylpropanoids, as seen in this study. The oil was able to scavenging the DPPH radical, displaying an inhibition varying from 19% to 74%, with an EC50 value of 16.2 +/- 1.9 microg mL(-1). In the bleaching of beta-carotene, the inhibition of the oil oxidation was 60.0 +/- 2.7%. The oil gave minimum inhibitory concentrations for the fungi Cladosporium cladosporioides and C. sphareospermum of 0.5 microg and 5.0 microg, respectively. The oil also showed significant brine shrimp larvicidal activity (LC50, 38.8 +/- 0.8 microg mL(-1)).

Topics: Animals; Antibiotics, Antineoplastic; Antifungal Agents; Antioxidants; Artemia; beta Carotene; Biphenyl Compounds; Cladosporium; Drug Screening Assays, Antitumor; Eugenol; Free Radical Scavengers; Fungi; Gas Chromatography-Mass Spectrometry; Linoleic Acid; Microbial Sensitivity Tests; Oils, Volatile; Oxidants; Picrates; Piper

A series of novel ketoprofen derivatives 4a-j bearing both amide and carbamate functionalities were prepared using benzotriazole. Selective reduction of ketoprofen produced hydroxy derivative 2, which reacts with one or 2 mol of 1-benzotriazole carboxylic acid chloride (1) gave benzotriazole derivatives 3a and 3b respectively. Antioxidative screenings revealed that the prepared compounds 3b and 4a-j possess excellent lipid peroxidation inhibition at 0.1 mM concentration. Two of the compounds 3b and 4 g also showed high soybean lipoxygenase inhibition activity, where as the amidocarbamate derivatives of ketoprofen showed only weak reducing activity against 1,1-diphenyl-2-picrylhydrazyl radicals. No selective antiviral effects were noted for the tested compounds against a broad variety of DNA and RNA viruses.

Topics: Antiviral Agents; Biphenyl Compounds; Carbamates; Cell Line; Cytostatic Agents; DNA Viruses; Drug Evaluation, Preclinical; Free Radical Scavengers; Glycine max; Inhibitory Concentration 50; Linoleic Acid; Lipid Peroxidation; Lipoxygenase; Lipoxygenase Inhibitors; Picrates; Quinolones; RNA Viruses

Antioxidant capacities of methanolic extract and fatty acid composition of three Centaurea species were investigated. The antioxidant capacity of the extracts was evaluated by different assays, including total phenolic content, phosphomolybdenum assay, free radical scavenging activity (DPPH assay), beta-carotene/linoleic acid bleaching assay, iron (III) and cupric reduction assay. The findings showed that the methanolic extract of Centaurea pulchella has the strongest antioxidant capacity compared to other two Centaurea species. The order of the antioxidant properties of Centaurea species were C. pulchella>C. patula>C. tchihatcheffii. Thirty fatty acids were identified in the oils of three Centaurea species. The major fatty acids of these species were found to be linoleic acid from C. pulchella and C. tchihatcheffii, and alpha-linolenic acid from C. patula. The study concluded that the Centaurea species can be used as a source of natural antioxidants and essential fatty acids.

Topics: Antioxidants; beta Carotene; Biphenyl Compounds; Centaurea; Chromatography, Gas; Copper; Fatty Acids; Iron; Linoleic Acid; Methanol; Phenols; Picrates; Plant Extracts; Plant Oils; Reducing Agents; Solvents; Turkey

Several studies indicated that bifidobacteria possessed strong antioxidant activity. In present study, the antioxidant activities of Bifidobacterium animalis 01 proteins were evaluated using six assays, namely, linoleic acid preoxidation assay, erythrocyte hemolysis assay, 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay, reducing power assay, hydroxyl (.OH) and superoxide radicals (.O(2)(-)) assays, in which the last two assays were measured by electron spin resonance (ESR). There were two kinds of B. animalis 01 proteins in this study, the regular B. animalis 01 protein (Pro-CK) and the B. animalis 01 selenium-contained protein (Pro-Se). Both Pro-CK and Pro-Se showed concentration dependent antioxidant activity in DPPH assay, reducing power assay and erythrocyte hemolysis assay. All results of six assays indicated that the antioxidant activity of the B. animalis 01 protein was improved remarkably after selenium was incorporated. The antioxidant activity of Pro-Se increased with the increase of selenium content in Pro-Se suggesting selenium played a positive role in enhancing the antioxidant activity of B. animalis 01 protein. Moreover, organic selenium was more effective than inorganic selenium on enhancing the hydroxyl radical scavenging ability of B. animalis 01 protein.

Topics: Antioxidants; Bacterial Proteins; Bifidobacterium; Biphenyl Compounds; Hemolysis; Humans; Hydroxyl Radical; Linoleic Acid; Oxidation-Reduction; Picrates; Selenium; Superoxides

In the present study, chemical compositions, antimicrobial and antioxidant activities of the essential oils of Sideritis erythrantha var. erythrantha (SE) and Sideritis erythrantha var. cedretorum (SC), which are endemic taxa in Turkey, were investigated. The essential oils obtained by hydrodistillation were analyzed by gas chromatography-mass spectrometry (GC-MS). α-Pinene was the major component of the essential oils of SC and SE. SC essential oil was as effective as antibiotic against methicillin-resistant Staphylococcus aureus (MRSA), vancomycin resistant Enterococcus faecalis (VRE), ampicillin resistant Haemophilusinfluenzae and vancomycin sensitive E. faecalis. Similarly, SE essential oil was also as effective as antibiotic against VRE and ampicillin resistant H. influenzae. Antioxidant activities of the essential oils of SC and SE were determined by 1,1-diphenyl-2-picrylhydrazyl (DPPH), β-carotene/linoleic acid and reducing power. Both essential oils exhibited weak antioxidant activity. This is the first report on antimicrobial and antioxidant activities of the essential oils of SC and SE.

Topics: Anti-Infective Agents; Antioxidants; Bacteria; beta Carotene; Biphenyl Compounds; Free Radical Scavengers; Gas Chromatography-Mass Spectrometry; Linoleic Acid; Microbial Sensitivity Tests; Oils, Volatile; Picrates; Reducing Agents; Sideritis; Turkey

The essential oil and methyl ester of hexane extract of Salvia chionantha Boiss. were analysed by GC and GC-MS. Totally, 54 components were detected in the essential oil and all of them were fully determined. Germacrene D (25.03%), β-caryophyllene (8.71%), spathulenol (5.86%) and α-humulene (4.82%) were identified as the major compounds. In the methylated hexane extract, 3-hydroxy hexadecanoic acid (39.39%), 3-hydroxy tetradecanoic acid (12.66%) and palmitic acid (12.02%) were the major fatty acids elucidated. The antioxidant activity of the essential oil and the hexane extract was determined by using four complementary test systems; namely, β-carotene-linoleic acid, DPPH() scavenging, ABTS(+)* scavenging, and CUPRAC assays. In β-carotene-linoleic acid assay, the extract showed 81.2±0.1% lipid peroxidation inhibition at 0.8 mg/mL concentration, while in ABTS(+)* assay the essential oil exhibited 77.4±0.5% inhibition at same concentration. Since, acetylcholinesterase and butyrylcholinesterase enzymes are taking place in pathogenesis of Alzheimer's disease, in vitro anticholinesterase activity of the essential oil and the extract was also studied spectrophotometrically. At 0.5mg/mL concentration, the essential oil showed moderate acetylcholinesterase (56.7±1.9%) and butyrylcholinesterase (41.7±2.9%) inhibitory activity, while the extract was only exhibited activity (63.1±0.8%) against butyrylcholinesterase enzyme. Hence, the essential oil may be useful as a moderate anticholinesterase agent, particularly against acetylcholinesterase.

Topics: Acetylcholinesterase; Antioxidants; beta Carotene; Biphenyl Compounds; Butyrylcholinesterase; Cholinesterase Inhibitors; Copper; Free Radical Scavengers; Free Radicals; Gas Chromatography-Mass Spectrometry; Hexanes; Indicators and Reagents; Linoleic Acid; Oils, Volatile; Oxidation-Reduction; Picrates; Plant Oils; Salvia

L-adrenaline belongs to a group of the compounds known as catecholamines, which play an important role in the regulation of physiological process in living organisms. The antioxidant activity and antioxidant mechanism of L-adrenaline was clarified using various in vitro antioxidant assays including 1,1-diphenyl-2-picryl-hydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS), N,N-dimethyl-p-phenylenediamine (DMPD(+)), and superoxide anion radicals (O(2)(-)) scavenging activity, hydrogen peroxide (H(2)O(2)), total antioxidant activity, ferric ions (Fe(3+)) and cupric ions (Cu(2+)) reducing ability, ferrous ions (Fe(2+)) chelating activity. L-adrenaline inhibited 74.2% lipid peroxidation of a linoleic acid emulsion at 30 microg/mL concentration. On the other hand, butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), alpha-tocopherol and trolox displayed 83.3, 82.1, 68.1 and 81.3% inhibition on the peroxidation of linoleic acid emulsion at the same concentration, respectively. BHA, BHT, alpha-tocopherol and trolox were used as reference antioxidants and radical scavenger compounds. Moreover, this study will bring an innovation for further studies related to antioxidant properties of L-adrenaline. According to present study, L-adrenaline had effective in vitro antioxidant and radical scavenging activity.

Topics: alpha-Tocopherol; Antioxidants; Benzothiazoles; Biphenyl Compounds; Butylated Hydroxyanisole; Butylated Hydroxytoluene; Chromans; Copper; Dose-Response Relationship, Drug; Epinephrine; Ferrous Compounds; Free Radical Scavengers; Hydrogen Peroxide; Linoleic Acid; Lipid Peroxidation; Oxidation-Reduction; Picrates; Piperidones; Structure-Activity Relationship; Sulfonic Acids; Superoxides

The antioxidant properties of virgin coconut oil produced through chilling and fermentation were investigated and compared with refined, bleached and deodorized coconut oil. Virgin coconut oil showed better antioxidant capacity than refined, bleached and deodorized coconut oil. The virgin coconut oil produced through the fermentation method had the strongest scavenging effect on 1,1-diphenyl-2-picrylhydrazyl and the highest antioxidant activity based on the beta-carotene-linoleate bleaching method. However, virgin coconut oil obtained through the chilling method had the highest reducing power. The major phenolic acids detected were ferulic acid and p-coumaric acid. Very high correlations were found between the total phenolic content and scavenging activity (r=0.91), and between the total phenolic content and reducing power (r=0.96). There was also a high correlation between total phenolic acids and beta-carotene bleaching activity. The study indicated that the contribution of antioxidant capacity in virgin coconut oil could be due to phenolic compounds.

Topics: Antioxidants; beta Carotene; Biphenyl Compounds; Cocos; Cold Temperature; Coumaric Acids; Fermentation; Food Handling; Linoleic Acid; Nuts; Phenols; Picrates; Plant Oils

Powdered rooibos tea extract (RTE), which is rich in polyphenols, is made from rooibos tea by freeze-drying. "Rooibos" is Afrikaans for "red bush," and the scientific name is "Aspalathus linearis." It is a broom-like member of the legume family of plants and is used to make an herbal tea which has been popular in South Africa for generations and is now consumed in many countries. In the present work, the anti-oxidative effect of RTE on oils and fats in autoxidation or thermal oxidation was studied, and it was confirmed that RTE has a very strong anti-oxidative effect on emulsifying oils owing to the water-soluble polyphenols such as rutin and quercetin contained in RTE. RTE was found to have a strong ability to quench radicals generated in the water phase, and to confer higher thermal stability against deep fat frying than tocopherol. But RTE showed little anti-oxidative effect on frying oil because of its lower oil-solubility.

Topics: Antioxidants; Ascorbic Acid; Aspalathus; Biphenyl Compounds; Citric Acid; Esters; Flavonoids; Free Radical Scavengers; Linoleic Acid; Lipid Metabolism; Oxidation-Reduction; Peroxides; Phenols; Phosphatidylethanolamines; Picrates; Plant Extracts; Polyphenols; Safflower Oil; Soybean Oil; Tea; Temperature; Time Factors

Catnip (Nepeta cataria) is an important medicinal herb belonging to the mint family, Lamiaceae. In this study, the in vitro antimicrobial and antioxidant activities of the essential oil and methanol extract from Nepeta cataria, and its essential oil composition were investigated. The essential oil, which has 4aalpha,7alpha,7abeta-nepetalactone (70.4%), 4aalpha,7alpha,7abeta-nepetalactone (6.0%), thymol (2.3%), and 4aalpha,7alpha, 7abeta3-nepetalactone (2.5%), as main components, exhibited activity against eleven bacteria, and twelve fungi and a yeast, C. albicans; with Minimum Inhibitory Concentrations (MIC) values ranging from 12.50 to 250 microl/ml; the methanol extract showed weaker activity. The samples were also subjected to a screening for their possible antioxidant activities by using 2.2-diphenyl-1-picrylhydrazyl (DPPH) and beta-carotene/linoleic acid assays. In DPPH assay, the extract showed slight antioxidant activity whereas the essential oil remained inactive. In the latter case, both the extract and the essential oil exerted weak activity having inhibiton ratios of linoleic acid oxidation at 16.4% and 27.0%, respectively. The weak antioxidative nature of the extract could be attributed to the low phenolic content, estimated as gallic acid equivalent at 22.6 +/- 2.07 microg/ml or 2.26%. In both systems, antioxidant capacity of BHT was determined in parallel experiments.

Topics: Anti-Infective Agents; Antioxidants; Bacteria; Biphenyl Compounds; Cyclopentane Monoterpenes; Cyclopentanes; Fungi; Gas Chromatography-Mass Spectrometry; Linoleic Acid; Methanol; Microbial Sensitivity Tests; Nepeta; Picrates; Plant Extracts; Plant Oils; Pyrones

Seven Morchella species were analyzed for their antioxidant activities in different test systems namely beta-carotene/linoleic acid, DPPH, reducing power, chelating effect and scavenging effect (%) on the stable ABTS*(+), in addition to their heavy metals, total phenolic and flavonoid contents. In beta-carotene/linoleic acid system, the most active mushrooms were M. esculenta var. umbrina and M.angusticeps. In the case of DPPH, methanol extract of M. conica showed high antioxidant activity. The reducing power of the methanol extracts of mushrooms increased with concentration. Chelating capacity of the extracts was also increased with the concentration. On the other hand, in 40 microg ml(-1) concentration, methanol extract of M. conica, exhibited the highest radical scavenging activity (78.66+/-2.07%) when reacted with the ABTS*(+) radical. Amounts of seven elements (Cu, Mn, Co, Zn, Fe, Ca, and Mg) and five heavy metals (Ni, Pb, Cd, Cr, and Al) were also determined in all species. M. conica was found to have the highest phenolic content among the samples. Flavonoid content of M. rotunda was also found superior (0.59+/-0.01 microg QEs/mg extract).

Topics: Agaricales; beta Carotene; Biphenyl Compounds; Chelating Agents; Flavonoids; Free Radical Scavengers; In Vitro Techniques; Indicators and Reagents; Linoleic Acid; Lipid Peroxidation; Metals; Oxidation-Reduction; Phenols; Picrates; Plant Extracts; Species Specificity

The consumption of red wine can provide substantial concentrations of antioxidant polyphenols, in particular grape anthocyanins (e.g., malvidin-3-O-beta-d-glucoside (1)) and specific red wine pigments formed by reaction between anthocyanins and other wine components such as catechin (3), ethanol, and hydroxycinnamic acids. In this work, the antioxidant properties of red wine pigments (RWPs) are evaluated by the DPPH assay and by inhibition of the heme-induced peroxidation of linoleic acid in acidic conditions (a model of antioxidant action in the gastric compartment). RWPs having a 1 and 3 moieties linked via a CH(3)-CH bridge appear more potent than the pigment with a direct 1-3 linkage. Pyranoanthocyanins derived from 1 reduce more DPPH radicals than 1 irrespective of the substitution of their additional aromatic ring. Pyranoanthocyanins are also efficient inhibitors of the heme-induced lipid peroxidation, although the highly hydrophilic pigment derived from pyruvic acid appears less active.

Topics: Anthocyanins; Antioxidants; Biphenyl Compounds; Heme; Hydrogen; Linoleic Acid; Lipid Peroxidation; Picrates; Wine

The chemical composition of the essential oil from cornmint (Mentha canadensis L.) was analyzed by GC/FID and GC-MS. The main constituents were menthol (41.2%) and menthone (20.4%). It was established that cornmint oil had antiradical activity with respect to the DPPH and hydroxyl (OH*) radicals. The concentrations necessary for 50% neutralization of the respective radicals (IC50) were 365.0 microg/mL for DPPH and 0.3 microg/mL for OH*, which was indicative that the antioxidant activity in terms of OH* was higher than that of quercetin. Cornmint oil chelated the Fe3+ ions present in the solution. The oil demonstrated antioxidant activity in a linoleic acid emulsion model system, where at 0.1% concentration it inhibited the formation of conjugated dienes by 57.1% and the generation of secondary oxidized products of linoleic acid by 76.1%.

Topics: Antioxidants; Biphenyl Compounds; Gas Chromatography-Mass Spectrometry; Hydroxyl Radical; Iron Chelating Agents; Linoleic Acid; Mentha; Odorants; Oils, Volatile; Oxidants; Picrates; Plant Leaves; Quercetin; Thiobarbituric Acid Reactive Substances

Two traditional Chinese medicines (Phlomis umbrosa Turcz. and Phlomis megalantha Diels), as well as five pure phenolic compounds (protocatechic, chlorogenic, benzoic, rosmarinic acid, and rutin) have been studied for antioxidant activities in acetone and methanol extracts from leaves. An HPLC method was developed to quantify the amounts of 14 phenolic compounds in the leaf extracts. The antioxidant capacities of the studied species are high. Almost all samples were capable of directly scavenging DPPH and superoxide free radicals, inhibiting linoleic acid oxidation, acting as reducing agents, and reducing plasmid DNA damage induced by hydroxyl radicals. Among different extracts, the acetone extract of P. megalantha exhibited the highest antioxidant activity. The major phenolic compounds identified were protocatechic, chlorogenic, caffeic, rosmarinic acid, and (-)-epicatechin. Antioxidant activities of pure compounds and correlation analysis indicated that protocatechic and rosmarinic acids were the major contributors to the observed antioxidant activities of the investigated Phlomis extracts.

Topics: Antioxidants; beta Carotene; Biphenyl Compounds; Chromatography, High Pressure Liquid; DNA Damage; Ferric Compounds; Flavonoids; Free Radical Scavengers; Linoleic Acid; Oxidants; Phenols; Phlomis; Picrates; Plant Extracts; Plant Leaves; Reducing Agents; Spectrophotometry, Ultraviolet; Superoxides

A polyacrylic acid (PAA)-protected platinum nanoparticle species (PAA-Pt) was prepared by alcohol reduction of hexachloroplatinate. The PAA-Pt nanoparticles were well dispersed and homogeneous in size with an average diameter of 2.0 +/- 0.4 nm (n = 200). We used electron spin resonance to quantify the residual peroxyl radical ([Formula: see text]) generated from 2,2-azobis (2-aminopropane) dihydrochloride (AAPH) by thermal decomposition in the presence of O(2) and a spectrophotometric method to quantify the residual 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical. PAA-Pt scavenged these two radicals in a dose-dependent manner. Platinum was the functional component. PAA-Pt reduced the rate of oxygen consumption required for linoleic acid peroxidation initiated by [Formula: see text] generated from AAPH, indicating inhibition of the propagation of linolate peroxidation. A thiobarbituric acid test also revealed dose-dependent inhibition of the linolate peroxidation by PAA-Pt. Fifty micromolar platinum, as PAA-Pt, completely quenched 250 microM DPPH radical for 5 min. Even when twice diluted in half, the PAA-Pt still quenched 100% of the 250 microM DPPH radical. The scavenging activity of PAA-Pt is durable. These observations suggest that PAA-Pt is an efficient scavenger of free radicals.

Topics: Amidines; Biphenyl Compounds; Free Radical Scavengers; Linoleic Acid; Lipid Peroxidation; Metal Nanoparticles; Peroxides; Picrates; Platinum

A series of 2'-hydroxy-chalcones and their oxidative cyclization products, aurones, have been synthesized and tested for their antioxidant and lipoxygenase inhibitory activity. The natural product aureusidin (31) was synthesized in high yield by a new approach. An extensive structure-relationship study was performed and revealed that several chalcones and aurones possess an appealing pharmacological profile combining high antioxidant and lipid peroxidation activity with potent soybean LOX inhibition.

Topics: Antioxidants; Benzofurans; Biphenyl Compounds; Chalcones; Linoleic Acid; Lipoxygenase; Lipoxygenase Inhibitors; Magnetic Resonance Spectroscopy; Mass Spectrometry; Picrates

Rosmarinus officinalis essential oil was separated into its hydrocarbon and oxygenated fractions. The major compounds in the hydrocarbon fraction were alpha-pinene (44.2%), camphene (24.5%), and limonene (11.7%), while in the oxygenated fraction they were 1,8-cineole (37.6%), camphor (16.5%), and bornyl acetate (21.4%). The hydrocarbon fraction was submitted to a hydroformylation process and the antioxidant activity of the product was screened by the DPPH and beta-carotene/linoleic acid tests. The hydroformylated fraction maintained the antioxidant activity of the whole oil. The MIC (minimal inhibitory concentration) and the MBC (minimal bactericidal concentration) of the essential oil, hydrocarbon, oxygenated and hydroformylated fractions were also tested on several microorganisms. Aeromonas sobria and Candida strains were the most susceptible micro-organisms. The hydroformylated fraction exhibited a MBC against Candida strains resistant to the other fractions.

Topics: Anti-Infective Agents; Antioxidants; Bacteria; beta Carotene; Biphenyl Compounds; Candida; Gas Chromatography-Mass Spectrometry; Linoleic Acid; Lipid Peroxidation; Microbial Sensitivity Tests; Oils, Volatile; Oxidants; Picrates; Rosmarinus

The chemiluminescent response of conjugated linoleic acid isomers (CLAs), linoleic acid (LA) and methyl linoleate (LAME) against the prooxidant t-butyl hydroperoxide (tBHP) was analyzed. The c9, t11-CLA and t10, c12-CLA isomers showed significant photoemission at the highest concentration used, while photoemission was not detected at any concentration of LA and LAME analyzed. These results show that CLAs are more susceptible to peroxidation than LA and LAME. Likewise, the effect of CLA, LA and LAME on lipid peroxidation of triglycerides rich in C20:5 omega3 and C22:6 omega3 (Tg omega3-PUFAs) was investigated. For that, chemiluminescence produced by triglycerides in the presence of tBHP, previously incubated with different concentrations of CLAs, LA and LAME (from 1 to 200 mM) was registered for 60 min. Triglycerides in the presence of t-BHP produced a peak of light emission (3151+/-134 RLUs) 5 min after addition. CLAs produced significant inhibition on photoemission, t10, c12-CLA being more effective than the c9, t11-CLA isomer. LA and LAME did not have an effect on lipid peroxidation of Tg omega3-PUFAs. CLA isomers, LA and LAME were also investigated for free radical scavenging properties against the stable radical (DPPH). Both CLA isomers reacted and quenched DPPH at all tested levels (from 5 to 25 mM), while LA and LAME did not show radical quenching activity even at the highest concentration tested. These data indicate that CLAs would provide protection against free radicals, but LA and LAME cannot.

Topics: Antioxidants; Biphenyl Compounds; Esters; Hydrazines; Isomerism; Light; Linoleic Acid; Linoleic Acids; Picrates

To estimate the preventive potential of Japanese traditional cereals against oxygen radical-related chronic diseases such as cardiovascular diseases and diabetes, antioxidant and radical-scavenging activities in the extracts of five Japanese traditional cereal grains were analyzed by using an assay system of lipid peroxidation and a radical compound, 1,1-diphenyl-2-picrylhydrazyl (DPPH). DPPH radical-scavenging activities in the extracts of Japanese cereal grains were divided into two groups. One group including Japanese sorghum, black rice and red rice showed strong radical-scavenging activities, but the other group including Japanese barnyard millet and foxtail millet did not exhibit significant radical-scavenging activities. The DPPH radical-scavenging activities of these extracts were closely correlated to the contents of phenolic compound in the extracts, but not to the sugar or protein content in the extracts. In contrast, all the methanol and water extracts of the cereal grains caused significant antioxidant activities against hydroperoxide generation in the peroxidation of linoleic acid, in which the water extracts of these cereal grains caused much higher antioxidant activities than the methanol extracts of the same cereals. These results suggest that Japanese traditional cereals contain qualitatively different principles associated with antioxidant and radical-scavenging activities, and possible principles responsible for the antioxidant and radical-scavenging activities in the cereal grains are discussed.

Topics: Antioxidants; Biphenyl Compounds; Edible Grain; Free Radical Scavengers; Hydrazines; Hydrogen Peroxide; Hydroxybenzoates; Japan; Linoleic Acid; Lipid Peroxidation; Methanol; Picrates; Plant Extracts; Water

To study antioxidant activities of different extracts of Senecio argunensis.. The antioxidant activities of S. argunensis extracts with acetoacetate, n-Butanol and water were detected by DPPH * free radical-scavenging method and beta-carotene/linoleic acid system.. The acetoacetate, n-Butanol and water extracts from S. argunensis eliminated DPPH * in dose-dependent manner, their EC50 values were 0.0198, 0.0219 and 0.092 mg/ml, respectively. The strength order of the antioxidant activities of the three parts in beta-carotene/linoleic acid system was acetoacetate, n-Butanol and water extracts.. The extracts of the three parts of S. argunensis all have antioxidant activities. Among these extracts, extracts with acetoacetate have the highest antioxidant activity.

Topics: Acetoacetates; Antioxidants; Asteraceae; beta Carotene; Biphenyl Compounds; Dose-Response Relationship, Drug; Free Radical Scavengers; Linoleic Acid; Picrates; Plant Extracts; Plant Leaves; Solvents

This study was designed to examine the in vitro antioxidant activities and rosmarinic acid levels of the methanol extracts of Salvia virgata, Salvia staminea and Salvia verbenaca. The extracts were screened for their possible antioxidant activity by two complementary test systems, namely DPPH free radical scavenging and beta-carotene/linoleic acid systems. In the first case, the most active plant was S. verbenaca (14.30+/-1.42 microg mg(-1)), followed by S. virgata (65.70+/-2.12 microg mg(-1)). S. staminae exhibited the weakest antioxidant activity in this test system of which IC(50) value is 75.40+/-0.57 microg mg(-1). In beta-carotene/linoleic acid test system, S. verbenaca extract was superior to the other extracts studied (inhibition value is 77.03%+/-0.42). Antioxidant activities of BHT, ascorbic acid, curcumin and alpha-tocopherol were determined in parallel experiments. Activity of rosmarinic acid was also screened for better establishing the relationship between rosmarinic acid level and antioxidant activity for the plant extracts. According to the results obtained by spectrophotometric analysis and further supported by HPLC, S. verbenaca has the highest rosmarinic acid level with a value of 29.30+/-0.24 microg mg(-1). Our results showed that the rosmarinic acid and its derivatives are more likely to be responsible for most of the observed antioxidant activities of Salvia species.

Topics: Antioxidants; beta Carotene; Biotechnology; Biphenyl Compounds; Chromatography, High Pressure Liquid; Cinnamates; Depsides; Free Radical Scavengers; Hydrazines; Linoleic Acid; Methanol; Models, Chemical; Picrates; Plant Extracts; Plant Leaves; Rosmarinic Acid; Salvia; Species Specificity; Turkey

This study is designed to examine the chemical composition and in vitro antioxidant activity of the essential oil and sub-fractions of the methanol extract of Marrubium globosum subsp. globosum. The GC and GC-MS analysis of the essential oil were resulted in the determination of 84 components representing 88.2% of the oil. The major constituents of the oil were spathulenol (15.8%), beta-caryophyllene (9.0%), caryophyllene oxide (7.9%), germacrene D (6.5%), and bicyclogermacrene (3.1%). Antioxidant activities of the samples were determined by three different test systems namely DPPH, beta-carotene/linoleic acid and reducing power assay. In DPPH system, the weakest radical scavenging activity was exhibited by the essential oil (1203.38+/-7.18 microg ml(-1)). Antioxidant activity of the polar sub-fraction of methanol extract was superior to the all samples tested with an EC(50) value of 157.26+/-1.12 microg ml(-1). In the second case, the inhibition capacity (%) of the polar sub-fraction of methanol extract (97.39%+/-0.84) was found the strongest one, which is almost equal to the inhibition capacity of positive control BHT (97.44%+/-0.74). In the case of reducing power assay, a similar activity pattern was observed as given in the first two systems. Polar sub-fraction was the strongest radical reducer when compared with the non-polar one, with an EC(50) value of 625.63+/-1.02 microg ml(-1). The amount of the total phenolics was highest in polar sub-fraction (25.60+/-0.74 microg/mg). A positive correlation was observed between the antioxidant activity potential and total phenolic level of the extracts. On the other hand, total flavonoid content was found equal for the both sub-fractions.

Topics: Antioxidants; beta Carotene; Biotechnology; Biphenyl Compounds; Chromatography, Gas; Flavonoids; Gas Chromatography-Mass Spectrometry; Hydrazines; Lamiaceae; Linoleic Acid; Marrubium; Methanol; Oils, Volatile; Phenol; Picrates; Plant Extracts

The antioxidant potential of ethanol extracts from defatted Bokbunja seed wastes generated during wine processing were estimated by radical scavenging abilities (DPPH(*), H(2)O(2), and O(2)(*-)), retardation of lipid oxidation, and iron ion-chelating characteristics. For comparison, ethanol extracts from seeds of fresh ripe Bokbunja fruits were also used. The ethanol extracts from the wine seed waste always showed higher scavenging activities against DPPH(*), H(2)O(2), and O(2)(*-) than those from the fresh seeds. The oxidation of linoleic acid in dimethylsulfoxide at 105 degrees C revealed that the kinetic behavior clearly obeyed pseudo-zero-order regardless of the linoleic acid concentration. The Fe(II)-chelating capacity was determined by the Freundlich isotherm. The results showed high potential and favorability of the two extracts for Fe(II) chelation. The Freundlich chelation capacities (mg(1-1/n)L(1/n)/g) of both ethanol extracts from seeds of fresh Bokbunja and wine processing wastes, tannic acid, and proanthocyanidin from Pinus radiata bark were 100, 224, 260, and 307, respectively. The Fe(III)-chelating properties of the ethanol extracts were considered to be deeply associated with its 3',4',5'-trihydroxyl (galloyl) group as with tannic acid.

Topics: Antioxidants; Biotechnology; Biphenyl Compounds; Chelating Agents; Ethanol; Free Radical Scavengers; Hydrazines; Hydrogen Peroxide; Iron; Linoleic Acid; Lipids; Oxygen; Picrates; Proanthocyanidins; Seeds; Tannins; Wine

Antioxidant activities and phenolic compositions of the active fractions of Salvia virgata Jacq. (Lamiaceae) from Turkey were examined. The aerial part of S. virgata was extracted with different solvents in an order of increasing polarity such as hexane, ethyl acetate, methanol, and 50% aqueous methanol using a Soxhlet apparatus. Water extract was also prepared from S. virgata by reflux. All solvent fractions were investigated for their total phenolic contents, total flavonoids, flavonols, qualitative-quantitative compositions (by HPLC-PDA analysis), iron(III) reductive activities, free radical scavenging activities (using DPPH*), and effect upon linoleic acid peroxidation activities; also, the peroxidation level was determined by the TBA method. The results of activity tests given as IC50 values were estimated from nonlinear algorithm and compared with standards, viz., butylated hydroxytoluene, ascorbic acid, and gallic acid. Polar fractions were found to be more active for free radical activity whereas nonpolar fractions protected the peroxidation of linoleic acid. Rosmarinic acid was the most abundant component in the extracts, followed by caffeic acid and lutelin-7- O-glycoside.

Topics: Antioxidants; beta Carotene; Biphenyl Compounds; Ferric Compounds; Ferrous Compounds; Flavonoids; Flavonols; Linoleic Acid; Lipid Peroxidation; Oxidation-Reduction; Phenols; Picrates; Salvia; Turkey

The antioxidant potential of N-acetylcysteine amide (NACA), also known as AD4, was assessed by employing different in vitro assays. These included reducing power, free radical scavenging capacities, peroxidation inhibiting activity through linoleic acid emulsion system and metal chelating capacity, as compared to NAC and three widely used antioxidants, alpha-tocopherol, ascorbic acid and butylated hydroxytoluene (BHT). Of the antioxidant properties that were investigated, NACA was shown to possess higher 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) radical scavenging ability and reducing power than NAC, at all the concentrations, whereas the scavenging ability of H(2)O(2) differed with concentration. While NACA had greater H(2)O(2) scavenging capacity at the highest concentration, NAC was better than NACA at lower concentrations. NAC and NACA had a 60% and 55% higher ability to prevent beta-carotene bleaching, respectively, as compared to control. The chelating activity of NACA was more than 50% that of the metal chelating capacity of EDTA and four and nine times that of BHT and alpha-tocopherol, respectively. When compared to NACA and NAC; alpha-tocopherol had higher DPPH scavenging abilities and BHT and alpha-tocopherol had better beta-carotene bleaching power. These findings provide evidence that the novel antioxidant, NACA, has indeed enhanced the antioxidant properties of NAC.

Topics: Acetylcysteine; Antioxidants; beta Carotene; Biphenyl Compounds; Chelating Agents; Dose-Response Relationship, Drug; Edetic Acid; Free Radical Scavengers; Free Radicals; Humans; Hydrazines; Hydrogen Peroxide; Linoleic Acid; Metals; Picrates; Sulfhydryl Compounds

The antioxidant activities of curcumin, its natural demethoxy derivatives (demethoxycurcumin, Dmc and bisdemethoxycurcumin, Bdmc) and metabolite hydrogenated derivatives (tetrahydrocurcumin, THC; hexahydrocurcumin, HHC; octahydrocurcumin; OHC) were comparatively studied using 2,2-diphenyl-1-picrylhydrazyl (DDPH) radical, 2,2'-azobis(2-amidinopropane)dihydrochloride (AAPH) induced linoleic oxidation and AAPH induced red blood cell hemolysis assays. Hydrogenated derivatives of curcumin exhibited stronger DPPH scavenging activity compared to curcumin and a reference antioxidant, trolox. The scavenging activity significantly decreased in the order THC>HHC=OHC>trolox>curcumin>Dmc>>>Bdmc. Stronger antioxidant activities toward lipid peroxidation and red blood cell hemolysis were also demonstrated in the hydrogenated derivatives. By the model of AAPH induced linoleic oxidation, the stoichiometric number of peroxyl radical that can be trapped per molecule (n) of hydrogenated derivatives were 3.4, 3.8 and 3.1 for THC, HHC and OHC, respectively. The number (n) of curcumin and Dmc were 2.7 and 2.0, respectively, which are comparable to trolox, while it was 1.4 for Bdmc. The inhibition of AAPH induced red blood cell hemolysis significantly decreased in the order OHC>THC=HHC>trolox>curcumin=Dmc. Results in all models demonstrated the lower antioxidant activity of the demethoxy derivatives, suggesting the ortho-methoxyphenolic groups of curcumin are involved in antioxidant activities. On the other hand, hydrogenation at conjugated double bonds of the central seven carbon chain and beta diketone of curcumin to THC, HHC and OHC remarkably enhance antioxidant activity.

Topics: Amidines; Antioxidants; Biphenyl Compounds; Chromans; Curcumin; Diarylheptanoids; Erythrocyte Membrane; Free Radical Scavengers; Free Radicals; Hemolysis; Humans; Hydrogenation; In Vitro Techniques; Linoleic Acid; Lipid Peroxidation; Molecular Structure; Oxidants; Picrates; Structure-Activity Relationship; Time Factors

The antioxidant properties of plants have been investigated, in the light of recent scientific developments, throughout the world due to their potent pharmacological activities and food viability. Basil (Ocimum basilicum L. Family Lamiaceae) is used as a kitchen herb and as an ornamental plant in house gardens. In the present study, the possible radical scavenging and antioxidant activity of the water (WEB) and ethanol extracts (EEB) of basil was investigated using different antioxidant methodologies: 1,1-diphenyl-2-picryl-hydrazyl (DPPH) free radical scavenging, scavenging of superoxide anion radical-generated non-enzymatic system, ferric thiocyanate method, reducing power, hydrogen peroxide scavenging and metal chelating activities. Experiments revealed that WEB and EEB have an antioxidant effects which are concentration-dependent. The total antioxidant activity was performed according to the ferric thiocyanate method. At the 50 microg/mL concentration, the inhibition effects of WEB and EEB on peroxidation of linoleic acid emulsion were found to be 94.8% and 97.5%, respectively. On the other hand, the percentage inhibition of a 50 microg/mL concentration of BHA, BHT and alpha-tocopherol was found to be 97.1%, 98.5% and 70.4% inhibition of peroxidation of linoleic acid emulsion, respectively. In addition, WEB and EEB had effective DPPH radical scavenging, superoxide anion radical scavenging, hydrogen peroxide scavenging, reducing power and metal chelating activities. Additionally, these various antioxidant activities were compared with BHA, BHT and alpha-tocopherol as reference antioxidants. The additional total phenolic content of these basil extracts was determined as the gallic acid equivalent and were found to be equivalent.

Topics: Antioxidants; Biphenyl Compounds; Free Radical Scavengers; Hydrogen Peroxide; Iron; Iron Chelating Agents; Linoleic Acid; Ocimum basilicum; Oxidation-Reduction; Picrates; Plant Extracts; Superoxides; Thiocyanates

The antioxidant properties of the methanol extract of leaves and flowers of Erica arborea and the ethyl acetate, butanol and water soluble fractions were investigated. The ethyl acetate extract was found to be the richest for phenolic and flavonoid content which showed the highest antioxidant activity.

Topics: Antioxidants; Biphenyl Compounds; Ericaceae; Ferrozine; Flowers; Humans; Inhibitory Concentration 50; Linoleic Acid; Phytotherapy; Picrates; Plant Extracts; Plant Leaves; Superoxides

Euphorbia acanthothamnos, E. macroclada and E. rigida were investigated for their antioxidant activity. The antioxidant potential of extracts of E. acanthothamnos, E. macroclada and E. rigida was evaluated using different complementary antioxidant tests.

Topics: Antioxidants; beta Carotene; Biphenyl Compounds; Euphorbia; Ferrozine; Humans; Inhibitory Concentration 50; Linoleic Acid; Medicine, Traditional; Phytotherapy; Picrates; Plant Extracts; Turkey

Regarding the involvement of free radicals and oxidative reactions in protein glycoxidation processes, compounds with antioxidant activities have been tested in order to reduce or to stop glycoxidation. In this study, we evaluated the antioxidant potential of several organic fractions of Teucrium polium extract using different model systems including total antioxidant capacity by the phosphomolybdenum method, ferric reducing antioxidant power and Trolox equivalent antioxidant capacity assays, antioxidant activity in linoleic acid emulsion system and scavenging of 1,1-diphenyl-2-picrylhydrazyl radical. The results indicated that the ethyl acetate (EtOAc) fraction of T. polium possesses the highest antioxidant activity and total phenolic and flavonoid contents. Given the link between glycation and oxidation, we proposed that the EtOAc fraction might possess significant in vitro antiglycation activities as well. Our data confirmed the inhibitory effect of EtOAc fraction on bovine serum albumin (BSA) glycoxidation measured in terms of advanced glycation end products (AGEs) and pentosidine formation as well as protein oxidation markers including protein carbonyl formation (PCO) and loss of protein thiols. Reducing sugars such as ribose and glucose increase fluorescence intensity of glycated BSA in terms of total AGEs and pentosidine during 21 day of exposure. Moreover, sugars cause more PCO formation and also oxidize thiol groups more in glycated than in native BSA. EtOAc extract at different concentrations (10-100 microg/ml) has significantly quenched the fluorescence intensity of glycated BSA. Furthermore, we demonstrated that the inhibitory effect of EtOAc extract in preventing oxidative protein damages including effect on PCO formation and thiol oxidation which are believe to form under the glycoxidation process. These results clearly demonstrate that, the EtOAc fraction, owning to its antioxidant content, is capable of suppressing the formation of AGEs and protein oxidation in vitro.

Topics: Antioxidants; Biphenyl Compounds; Glycation End Products, Advanced; Humans; In Vitro Techniques; Linoleic Acid; Oxidants; Phytotherapy; Picrates; Plant Components, Aerial; Plant Extracts; Teucrium

Vanilla extract was prepared by extraction of cured vanilla beans with aqueous ethyl alcohol (60%). The extract was profiled by HPLC, wherein major compounds, viz., vanillic acid, 4-hydroxybenzyl alcohol, 4-hydroxy-3-methoxybenzyl alcohol, 4-hydroxybenzaldehyde and vanillin, could be identified and separated. Extract and pure standard compounds were screened for antioxidant activity using beta-carotene-linoleate and DPPH in vitro model systems. At a concentration of 200 ppm, the extract showed 26% and 43% of antioxidant activity by beta-carotene-linoleate and DPPH methods, respectively, in comparison to corresponding values of 93% and 92% for BHA. Interestingly, 4-hydroxy-3-methoxybenzyl alcohol and 4-hydroxybenzyl alcohol exhibited antioxidant activity of 65% and 45% by beta-carotene-linoleate method and 90% and 50% by DPPH methods, respectively. In contrast, pure vanillin exhibited much lower antioxidant activity. The present study points toward the potential use of vanilla extract components as antioxidants for food preservation and in health supplements as nutraceuticals.

Topics: Antioxidants; Benzaldehydes; beta Carotene; Biphenyl Compounds; Chromatography, High Pressure Liquid; Linoleic Acid; Picrates; Plant Extracts; Seeds; Vanilla

Phenolics were extracted from litchi fruit pericarp (LFP) tissues, purified and their antioxidant properties analyzed. LFP phenolics strongly inhibited linoleic acid oxidation and exhibited a dose-dependent free-radical scavenging activity against alpha,alpha-diphenyl-beta-picrylhydrazyl (DPPH*) and hydroxyl radicals and superoxide anions. The degradation of deoxyribose by hydroxyl radicals was inhibited by phenolics acting mainly as iron ion chelators, rather than by directly scavenging the radicals. Phenolics from litchi fruit pericarp were found to display similar reducing power activity as ascorbic acid. The effect of phenolic compound treatment on pericarp browning and electrolyte leakage of litchi fruit was also evaluated and it was observed that application of exogenous litchi phenolics to harvested litchi fruit significantly prevented pericarp browning and delayed increases in electrolyte leakage. These results suggest that litchi pericarp tissue phenolics could be beneficial in scavenging free radicals, maintaining membrane integrity and, thereby inhibiting pericarp browning of litchi fruit.

Topics: Anions; Antioxidants; Biphenyl Compounds; Chemistry; Dose-Response Relationship, Drug; Electrolytes; Free Radicals; Hydrazines; Hydroxyl Radical; Linoleic Acid; Lipid Peroxidation; Litchi; Phenol; Picrates; Plant Extracts; Superoxides; Time Factors

Chinese water chestnut (CWC) is one of the most popular foods among Asian people due to its special taste and medical function. Experiments were conducted to test the antioxidant activity and then determine the major phenolic compound components present in CWC. CWC phenolic extract strongly inhibited linoleic acid oxidation and exhibited a dose-dependent free-radical scavenging activity against alpha,alpha-diphenyl-beta-picrylhydrazyl (DPPH) radicals, superoxide anions and hydroxyl radicals, which was superior to ascorbic acid and butylated hydroxytoluene (BHT), two commercial used antioxidants. Furthermore, the CWC extract was found to have a relatively higher reducing power, compared with BHT. The major phenolic compounds present in CWC tissues were extracted, purified and identified by high-performance liquid chromatograph (HPLC) as (-)-gallocatechin gallate, (-)-epicatechin gallate and (+)-catechin gallate. This study suggests that CWC tissues exhibit great potential for antioxidant activity and may be useful for their nutritional and medicinal functions.

Topics: Antioxidants; Biphenyl Compounds; Butylated Hydroxytoluene; Catechin; Chemistry; Chromatography, High Pressure Liquid; Dose-Response Relationship, Drug; Eleocharis; Free Radicals; Hydrazines; Linoleic Acid; Lipid Peroxidation; Models, Chemical; Phenol; Picrates

The free radical scavenging capacity and antioxidant activities of the methanolic extract of Cinnamomum verum leaf (CLE) were studied and compared to antioxidant compounds like trolox, butylated hydroxyl anisole, gallic acid and ascorbic acid. The CLE exhibited free radical scavenging activity, especially against DPPH radical and ABTS radical cation. They also exhibited reducing power and metal ion chelating activity, along with hydroxyl radical scavenging activity. The peroxidation inhibiting activity of CLE recorded using the linoleic acid emulsion system, showed very good antioxidant activity.

Topics: Antioxidants; Benzothiazoles; Biphenyl Compounds; Chelating Agents; Cinnamomum; Free Radical Scavengers; Hydroxyl Radical; Linoleic Acid; Methanol; Picrates; Plant Extracts; Plant Leaves; Solvents; Spectrophotometry, Ultraviolet; Sulfonic Acids

Caffeic acid (3,4-dihydroxycinnamic acid) is among the major hydroxycinnamic acids present in wine; sinapic acid, which is a potent antioxidant. It has also been identified as one of the active antioxidant. In the present study, the antioxidant properties of the caffeic acid were evaluated by using different in vitro antioxidant assays such as 2-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging, 1,1-diphenyl-2-picryl-hydrazyl free radical (DPPH) scavenging, total antioxidant activity by ferric thiocyanate method, total reductive capability using the potassium ferricyanide reduction method, superoxide anion radical scavenging and metal chelating activities. alpha-Tocopherol, trolox, a water-soluble analogue of tocopherol, butylated hydroxyanisole (BHA), and butylated hydroxytoluene (BHT) were used as the reference antioxidant compounds. At the concentrations of 10 and 30 microg/mL, caffeic acid showed 68.2 and 75.8% inhibition on lipid peroxidation of linoleic acid emulsion, respectively. On the other hand, 20 microg/mL of standard antioxidant such as BHA, BHT, alpha-tocopherol and trolox indicated an inhibition of 74.4, 71.2, 54.7 and 20.1% on peroxidation of linoleic acid emulsion, respectively. In addition, caffeic acid is an effective ABTS(+) scavenging, DPPH scavenging, superoxide anion radical scavenging, total reducing power and metal chelating on ferrous ions activities.

Topics: alpha-Tocopherol; Antioxidants; Benzothiazoles; Biphenyl Compounds; Butylated Hydroxyanisole; Butylated Hydroxytoluene; Caffeic Acids; Chelating Agents; Chromans; Dose-Response Relationship, Drug; Emulsions; Ferricyanides; Ferrous Compounds; Free Radical Scavengers; Hydrazines; Iron; Linoleic Acid; Lipid Peroxidation; Picrates; Reducing Agents; Sulfonic Acids; Superoxides; Thiocyanates

L-carnitine plays an important regulatory role in the mitochondrial transport of long-chain free fatty acids. In this study, the antioxidant activity of L-carnitine was investigated as in vitro. The antioxidant properties of the L-carnitine were evaluated by using different antioxidant assays such as 1, 1-diphenyl-2-picryl-hydrazyl free radical (DPPH.) scavenging, total antioxidant activity, reducing power, superoxide anion radical scavenging, hydrogen peroxide scavenging and metal chelating activities. Total antioxidant activity was measured according to ferric thiocyanate method. alpha-tocopherol and trolox, a water-soluble analogue of tocopherol, were used as the reference antioxidant compounds. At the concentrations of 15, 30 and 45 microg/mL, l-carnitine showed 94.6%, 95.4% and 97.1% inhibition on lipid peroxidation of linoleic acid emulsion, respectively. On the other hand, 45 microg/mL of standard antioxidant such as alpha-tocopherol and trolox indicated an inhibition of 88.8% and 86.2% on peroxidation of linoleic acid emulsion, respectively. In addition, L-carnitine had an effective DPPH. scavenging, superoxide anion radical scavenging, hydrogen peroxide scavenging, total reducing power and metal chelating on ferrous ions activities. Also, those various antioxidant activities were compared to alpha-tocopherol and trolox as references antioxidants.

Topics: alpha-Tocopherol; Antioxidants; Biphenyl Compounds; Carnitine; Chromans; Free Radical Scavengers; Free Radicals; Hydrazines; Hydrogen Peroxide; In Vitro Techniques; Linoleic Acid; Lipid Peroxidation; Picrates

The antiradical properties of water-soluble components of both natural and roasted barley were determined in vitro, by means of DPPH* assay and the linoleic acid-beta-carotene system, and ex vivo, in rat liver hepatocyte microsomes against lipid peroxidation induced by CCl4. The results show the occurrence in natural barley of weak antioxidant components. These are able to react against low reactive peroxyl radicals, but offer little protection against stable DPPH radicals deriving from peroxidation in microsomal lipids. Conversely, roasted barley yielded strong antioxidant components that are able to efficiently scavenge free radicals in any system used. The results show that the barley grain roasting process induces the formation of soluble Maillard reaction products with powerful antiradical activity. From roasted barley solution (barley coffee) was isolated a brown high molecular mass melanoidinic component, resistant to acidic hydrolysis, that is responsible for most of the barley coffee antioxidant activity in the biosystem.

Topics: Animals; Antioxidants; beta Carotene; Biphenyl Compounds; Carbon Tetrachloride; Free Radical Scavengers; Hordeum; Hot Temperature; Linoleic Acid; Lipid Peroxidation; Maillard Reaction; Microsomes, Liver; Picrates; Polymers; Rats

In recent years, the incidence of skin cancer has risen remarkably. Sun light, especially the included ultraviolet (UV)-radiation, is seen as important trigger for the development of skin cancer. Thus, there is an increasing interest in the development of UV-protective substances to use them as sun care products. One approach is the topical application of herbal antioxidants. Plant-derived antioxidants are often extracts and therefore contain a complex mixture of constituents, like flavonoids and polyphenols, which contribute to the overall activity of the extract. In the present study an extract from buckwheat herb was compared to rutin, which is the main constituent of the extract, regarding their antioxidant and radical scavenging activity. Additionally, the photoprotective properties of the extract were compared to those of a commercial UV absorber. The antioxidant activity was quantified regarding the reactivity versus the 1,1-diphenyl-2-picryl-hydrazyl radical (DPPH). The photoprotective properties of the extract were examined by the inhibition of the photosensitized lipid peroxidation of linolic acid. In the DPPH assay, the extract had significantly better antioxidant activity than pure rutin. The extract prevented more effectively the UV-induced peroxidation of linolic acid than rutin itself or the commercial UV absorber. The use of the extract from buckwheat herb seems to be more beneficial than the use of pure rutin. This can be referred to the presence of minor phenolic compounds in the extract. The results indicate that it is advisable to use antioxidants rather than only UV absorber to obtain a maximum of photo protection.

Topics: Algorithms; Antioxidants; Biphenyl Compounds; Fagopyrum; Ketoprofen; Linoleic Acid; Lipid Peroxidation; Oxidation-Reduction; Picrates; Plant Extracts; Radiation-Protective Agents; Rutin; Solutions; Ultraviolet Rays

Antioxidative effects of methanolic extracts from six wild European Lamiaceae species have been studied with the use of three in vitro assays. The ability of scavenging free radicals was measured by DPPH reduction spectrophotometric assay. The reducing potential towards transition metals was tested by phosphomolybdenum method and the inhibition of lipid oxidation was tested by Fe/ascorbate system with photometric TBARS detection. All studied herbs exposed strong antioxidant capability, but the results were different for each species depending on the applied test. In DPPH scavenging the order from strongest to the weakest was: Leonurus cardiaca, Lamium album, Marrubium vulgare, Stachys officinalis, Lamium purpureum, Galeopsis speciosa. With phosphomolybdenum method the extract of S. officinalis was the strongest in both 40 degrees Celsius and 90 degrees Celsius but other species acted differently in both temperatures. In lipid peroxidation assay, the maximum inhibition of 78% was reached by S. officinalis and M. vulgare, whereas for both Lamium sp. and L. cardiaca slightly exceeded 70% and for G. speciosa reached 65%. The observed differences indicate the complexity of involved mechanisms and support the necessity of combining several assays in studying the antioxidant potential of medicinal plants.

Topics: Antioxidants; Biphenyl Compounds; Flavonoids; Hydrazines; Lamiaceae; Linoleic Acid; Lipid Peroxidation; Molybdenum; Phenols; Picrates; Plant Extracts; Plants, Medicinal; Polyphenols

The antioxidant capacity (AOC) of three representative citrus limonoids, limonin, nomilin, and limonin glucoside, was examined by the oxygen radical absorbance capacity (ORAC), Trolox equivalent antioxidant capacity (TEAC), beta-carotene-linoleic acid bleaching, and 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical scavenging assays. Pure compounds and proper negative (cinnamic acid) and positive (2,6-di-tert-butyl-4-methylphenol (BHT) and ascorbic acid) controls were used to remove any ambiguity in interpreting results. In all cases, limonin and nomilin gave results equivalent to those of cinnamic acid, indicating that they do not possess any inherent AOC and should not be considered antioxidants. Similar results were observed for limonin glucoside, with the exception of an anomalous result obtained from the beta-carotene-linoleic acid bleaching assay. Limonin glucoside was deemed not to be an antioxidant on the basis of the three unequivocal assays.

Topics: Antioxidants; Benzoxepins; beta Carotene; Biphenyl Compounds; Chromans; Glucosides; Limonins; Linoleic Acid; Picrates; Reactive Oxygen Species

Because of increased safety concerns about synthetic antioxidants, exploitation of cheaper and safer sources of antioxidants based on natural origin is the focus of research nowadays. Rhazya stricta is a medicinally important plant native to South Asia. Extraction of antioxidants was carried out in different solvent systems, i.e., water, 80% methanol, 70% ethanol, and diethyl ether. The methanolic extract exhibited the highest total phenolic content among the extracts; therefore for further studies the methanolic extract was employed. Antioxidant activity measurement in the linoleic acid system, metal chelating activity, reducing power, scavenging effect on 1,1-diphenyl-2-picrylhydrazyl free radical, and superoxide anion radical scavenging activity were taken as the parameters for assessment of antioxidant potential of methanolic extracts. Results were compared with alpha-tocopherol and the synthetic antioxidant butylated hydroxyanisole. The antioxidant potential of methanolic extracts of R. stricta leaves was comparable with previously exploited potent antioxidants and is strongly concentration dependent.

Topics: alpha-Tocopherol; Antioxidants; Apocynaceae; Biphenyl Compounds; Butylated Hydroxyanisole; Chelating Agents; Free Radical Scavengers; Iron; Linoleic Acid; Methanol; Oxidation-Reduction; Phenols; Picrates; Plant Extracts; Plant Leaves; Superoxides

The antioxidant activity of a commercial rectified clove leaf essential oil (Eugenia caryophyllus) and its main constituent eugenol was tested. This essential oil comprises in total 23 identified constituents, among them eugenol (76.8%), followed by beta-caryophyllene (17.4%), alpha-humulene (2.1%), and eugenyl acetate (1.2%) as the main components. The essential oil from clove demonstrated scavenging activity against the 2,2-diphenyl-1-picryl hydracyl (DPPH) radical at concentrations lower than the concentrations of eugenol, butylated hydroxytoluene (BHT), and butylated hydroxyanisole (BHA). This essential oil also showed a significant inhibitory effect against hydroxyl radicals and acted as an iron chelator. With respect to the lipid peroxidation, the inhibitory activity of clove oil determined using a linoleic acid emulsion system indicated a higher antioxidant activity than the standard BHT.

Topics: Antioxidants; Biphenyl Compounds; Butylated Hydroxyanisole; Butylated Hydroxytoluene; Eugenol; Free Radical Scavengers; Linoleic Acid; Monocyclic Sesquiterpenes; Oils, Volatile; Picrates; Plant Leaves; Polycyclic Sesquiterpenes; Sesquiterpenes; Syzygium; Thiobarbituric Acid Reactive Substances

Pregnancy is a condition that favors oxidative stress by reactive oxygen species. Oxidative stress is involved in the etiopathogenesis of disorders of pregnancy such as pre-eclampsia. An antioxidant effect of estrogens has been described and a putative role of them as antioxidants has been proposed. The aim of this work was to evaluate in vitro the antioxidant properties of dehydroepiandrosterone sulfate, estradiol, estriol, progesterone, and testosterone, five steroid hormones present in the maternofetal circulation.. The antioxidant properties of the hormones were evaluated by two methods: 1. their antioxidant effect on the auto-oxidation of linoleic acid, a hydrogen atom transfer reaction; 2. diphenylpicrylhydrazyl-scavenging capacity, a single electron transfer reaction.. Of the five hormones tested, only estradiol and estriol at 10 microM concentration exerted a strong antioxidant effect of 81.73 and 70.97% respectively on linoleic acid auto-oxidation, at the end-point of the reaction. Likewise, only these two hormones showed radical-scavenging activity on diphenylpicrylhydrazyl, noticeable only at supraphysiological concentrations of 1 mM.. Estradiol and estriol could play a role as antioxidants for maternofetal autoprotection in addition to their hormonal activity, but this role could be preferentially exerted by estriol due to its higher concentrations exhibited during pregnancy. In vivo studies are necessary to shed light on this issue.

Topics: Adult; Antioxidants; Biphenyl Compounds; Dehydroepiandrosterone Sulfate; Dose-Response Relationship, Drug; Estradiol; Estriol; Estrogens; Female; Humans; Hydrazines; In Vitro Techniques; Linoleic Acid; Lipid Peroxidation; Oxidation-Reduction; Oxidative Stress; Picrates; Pregnancy; Progesterone; Reactive Oxygen Species; Testosterone

Pectin was dissolved in deionized distilled water (2%, vol/vol) and irradiated at 20 kGy using a Co-60 gamma ray irradiator. The resulting solution was dialyzed and lyophilized. The samples were separated into three groups to estimate their antioxidant and cancer cell proliferation effects: non-irradiated (0 kGy), irradiated (20 kGy), and dialyzed (20 kGy-F, mol wt <10,000) samples. Antioxidant properties of each treatment was tested by a beta-carotene-linoleic acid bleaching assay and electron donating ability and compared for antioxidant index, which indicated that the activity was higher in the order of 20 kGy-F > 20 kGy > 0 kGy. Spleen cell survival effect of the irradiated pectin (20 kGy) and dialyzed (20 kGy-F) samples was higher than the non-irradiated control (0 kGy). The pectins inhibited growth of the cancer cell in the order of 20 kGy- F > 20 kGy > 0 kGy. The Ames test revealed that none of the fractions was mutagenic, and there was no indication of a dose-dependent response for any of the samples. These results suggest that a functional pectin oligosaccharide can be produced by irradiation for the food industry without any chemical treatment.

Topics: Antioxidants; beta Carotene; Biphenyl Compounds; Cell Division; Cell Line, Tumor; Citrus; Free Radical Scavengers; Fruit; Gamma Rays; Humans; Linoleic Acid; Mutagenicity Tests; Neoplasms; Oligosaccharides; Oxidation-Reduction; Pectins; Picrates

The capacity of polyphenolic compounds to reduce the beta-carotene-linoleic acid cooxidation enzymatically induced by soybean lipoxygenase was assayed to determine their comprehensive antioxidant ability. The inhibition of the coupled oxidation is a well-known spectrophotometric method for the antioxidant activity measurement. A modification of this method is proposed to reduce assay time and to gain simplicity. The antioxidant abilities of several polyphenols were determined, and quercetin and sinapic acid were most active. These results were compared to those obtained by the DPPH* procedure to evaluate the free radical scavenging contribution to the total protective action. The highest values of antiradical activity were found for ellagic and quercetin.

Topics: Antioxidants; beta Carotene; Biphenyl Compounds; Flavonoids; Free Radicals; Kinetics; Linoleic Acid; Lipoxygenase; Molecular Structure; Oxidation-Reduction; Phenols; Picrates; Polyphenols; Solutions; Spectrum Analysis

Corni fructus has been used as a tonic, analgesic, and diuretic in Korean herbal medicine. The present investigation was undertaken to evaluate the antioxidative effect of corni fructus and its capacity to protect cells against oxidative damage. The radical scavenging activity of corni fructus extracts was measured using 1,1-diphenyl-2-picrylhydrazyl (DPPH), and the antioxidant activity was determined by measuring the peroxide value in a linoleic acid emulsion system. In addition, human umbilical vein endothelial cells (HUVECs) were treated with corni fructus extracts and incubated with H(2)O(2) to investigate protection against apoptosis induction. Both ethanol and water extracts of corni fructus produced higher DPPH radical scavenging activity than hexane, chloroform, and ethyl acetate extracts. Strong antioxidative activities of both water and ethanol extracts were observed in an emulsion system containing linoleic acid and phosphate buffer. The incubation of HUVECs with the addition of ethanol extract significantly decreased H(2)O(2)-initiated damage of endothelial cells, but the water extract did not. The pretreatment with ethanol extract, but not with water extract, significantly decreased apoptotic damage of the H(2)O(2)-treated HUVECs and kept the morphological normality. This study demonstrates that corni fructus is a potent antioxidant substance, and suggests that further investigation is needed to characterize the difference between extract types and to identify its antioxidant compounds.

Topics: Antioxidants; Apoptosis; Biphenyl Compounds; Cell Division; Cornus; Emulsions; Endothelial Cells; Free Radical Scavengers; Humans; Hydrogen Peroxide; Hydroxyl Radical; Linoleic Acid; Oxidative Stress; Phosphates; Phytotherapy; Picrates; Plant Extracts; Umbilical Veins

The enzymatic hydrolysates from pollen Cistus ladaniferus were digested and prepared using three kinds of enzymes (pepsin, trypsin, and papain) and the antioxidative properties were investigated. The yields, total phenolic contents, and protein contents of these hydrolysates were as follows: yields (about 21-45%), total phenolics (10.39-14.33 microg/mg sample powder), and proteins (129.62-137.35 microg/mg sample powder), respectively. The hydrolysates possessed strongly antioxidative and scavenging abilities against reactive oxygen species. The present studies revealed that hydrolysates from honeybee-collected pollen are of benefit not only to the materials of health food diets, but also to patients with various diseases such as cancer, cardiovascular diseases, and diabetes.

Topics: Amidines; Antioxidants; Biphenyl Compounds; Cistus; Electrophoresis, Polyacrylamide Gel; Hydrogen-Ion Concentration; Hydroxyl Radical; Indicators and Reagents; Linoleic Acid; Oxidants; Oxygen; Papain; Pepsin A; Phenol; Picrates; Pollen; Protein Hydrolysates; Reactive Oxygen Species; Superoxides; Time Factors; Trypsin

Recent evidence shows that plant polyphenols exhibit antioxidant and radical scavenging properties. By three separate and complementary methods--DPPH assay, beta-carotene-linoleic acid assay and NBT-reduction assay it was established that a polyphenol-rich extract from the medicinal plant Geranium sanguineum L. with strong anti-influenza virus activity, possessed antioxidant and radical scavenging capacities. For comparative reasons caffeic acid and the synthetic antioxidant BHT were used. Total soluble phenolic constituents of the MeOH extract measured by Folin-Ciocalteu reagent were found as 34.60% (w/w). Further it was demonstrated that the EtOAc fraction, retaining the majority of the in vivo protective effect exhibited a strong O2-scavenging activity while the n-BuOH fraction, containing the majority of the in vitro antiviral activity provoked generation of O2-. The O2- scavenging activity of all three preparations correlated with the rate of the protective effect shown in the murine model of experimental influenza virus infection. The present results are in accordance with our intensive studies on the mode of the protective effect of the plant extract which showed positively that the protection may possibly be attributed to the combination of more than one biological activities and that the use of antioxidants might be an useful approach in the treatment of influenza infection.

Topics: Animals; Antioxidants; Antiviral Agents; beta Carotene; Biphenyl Compounds; Bulgaria; Cells, Cultured; Cytopathogenic Effect, Viral; Dogs; Dose-Response Relationship, Drug; Enzyme-Linked Immunosorbent Assay; Flavonoids; Free Radical Scavengers; Geranium; Hemagglutination; Hemagglutinins; Hydrazines; Influenza A virus; Linoleic Acid; Mice; Orthomyxoviridae Infections; Phenols; Picrates; Plant Extracts; Polyphenols; Spectrophotometry; Superoxides

Scavenging activity of hydroxyethyl chitosan sulfate (HCS) against 2,2-diphenyl-1-picrylhydrazyl (DPPH), hydroxyl and carbon-centered radical species were studied using electron spin resonance (ESR) spectroscopy. In addition, its antioxidant activity to retard lipid peroxidation was also evaluated in a linoleic acid model system. HCS could scavenge DPPH (33.78%, 2.5 mg/mL) and carbon-centered radicals (67.74%, 0.25 mg/mL) effectively. However, chitosan sulfate did not exhibit any scavenging activity against hydroxyl radicals, but increased its generation. This was different from the published literature and was presumed due to the loss of chelating ability on Fe2+. This assumption could further confirm from the results obtained for Fe2+-ferrozine method that upon sulfation chitooligosaccharides lost its chelation properties. Therefore, HCS can be identified as antioxidant that effectively scavenges carbon centered radicals to retard lipid peroxidation.

Topics: Antioxidants; Biphenyl Compounds; Carbon; Chitin; Chitosan; Dose-Response Relationship, Drug; Edetic Acid; Electron Spin Resonance Spectroscopy; Free Radical Scavengers; Free Radicals; Indicators and Reagents; Iron; Linoleic Acid; Lipid Peroxidation; Magnetic Resonance Spectroscopy; Models, Chemical; Oligosaccharides; Picrates; Spectrophotometry; Time Factors

It is currently accepted that the consumption of fruit-derived antioxidants such as vitamin C, carotenoids, and flavonoids provides a preventive effect against cardiovascular disease. The purpose of the present study was to investigate potential cardiovascular protective properties of aqueous and 70% ethanol extracts from kiwifruit by analyzing the antioxidative, antihypertensive, hypocholesterolemic, and fibrinolytic activities in vitro. Aqueous and 70% ethanol extracts at 50 mg/ml showed DPPH-radical scavenging activities of 72.31% and 70.75%, respectively. Total antioxidant activity in linoleic acid emulsion was 85-88% at 10 mg/ml and 96-98% at 50 mg/ml of kiwifruit extract. Inhibitory activities against angiogensin I-converting enzyme of kiwifruit extracts were 21-26% at 10 mg/ml and 46-49% at 50 mg/ml, and inhibitory activities on HMG-CoA reductase were 13-14% at 10 mg/ml and 19-30% at 50 mg/ml. Fibrinolytic activity of kiwifruit was also observed at a high concentration of 100 mg/ml in both aqueous and 70% EtOH extracts. Based on our results, kiwifruit have potential cardiovascular protective properties in vitro.

Topics: Angiotensin-Converting Enzyme Inhibitors; Animals; Anticholesteremic Agents; Antihypertensive Agents; Antioxidants; Biphenyl Compounds; Cardiovascular Agents; Fibrinolysin; Fibrinolytic Agents; Free Radical Scavengers; Fruit; Humans; Hydrazines; Hydroxymethylglutaryl-CoA Reductase Inhibitors; In Vitro Techniques; Linoleic Acid; Male; Picrates; Plant Extracts; Rats; Rats, Sprague-Dawley

The chemical composition and antioxidant activity of different extracts (diethyl ether, ethyl acetate and n-butanol) obtained from Teucrium species (T. chamaedrys, T. montanum, T. polium) were investigated in this work. Phytochemical screening of the plant extracts proved the presence of flavonoids luteolin, apigenin and/or diosmetin. The chemical composition of extracts was evaluated by HPLC and spectrophotometry. Antioxidant activities of the extracts were evaluated using three complementary in vitro assays: inhibition of DPPH (1,1-diphenyl-2-picrylhydrazyl) radical, inhibition of hydroxyl radicals and protection of beta-carotene-linoleic acid model system. In the first two assays, strong inhibitory activity was shown by T. montanum and T. chamaedrys extracts. In the beta-carotene-linoleic acid model system, extracts from T. polium showed remarkable activity. These findings demonstrated that Teucrium species possess free radical and hydroxyl radical scavenging activity as well as antioxidant activity in vitro.

Topics: Antioxidants; beta Carotene; Biphenyl Compounds; Chromatography, High Pressure Liquid; Flavonoids; Hydrazines; Hydroxyl Radical; Indicators and Reagents; Linoleic Acid; Oxidants; Picrates; Plant Extracts; Solvents; Species Specificity; Spectrophotometry, Ultraviolet; Teucrium

Morphine is implicated in diverse functions, from development to immune modulation in the central and peripheral nervous systems. It has also been used extensively in the clinical management of pain due to its potent analgesic effect. This study was designed to evaluate the in vitro antioxidant capacity of morphine using different antioxidant tests, including total antioxidant activity, reducing power, free radical scavenging, superoxide anion radical scavenging, hydrogen peroxide scavenging and metal chelating activities. Morphine exhibited strong total antioxidant activity. The concentrations of 25, 50 and 75 microgml(-1) of morphine showed 79.1, 84.3 and 92.3% inhibition on peroxidation of linoleic acid emulsion, respectively. On the other hand, at 75 microgml(-1) concentration of standard antioxidant, such as butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT) and alpha-tocopherol, exhibited 88.7, 94.5 and 70.4% inhibition on peroxidation of linoleic acid emulsion, respectively. In addition, morphine had effective reducing power, free radical scavenging, superoxide anion radical scavenging, hydrogen peroxide scavenging and metal chelating activities at the same concentrations (25, 50 and 75 microgml(-1)). These various antioxidant activities were compared to standard antioxidants such as BHA, BHT and alpha-tocopherol.

Topics: alpha-Tocopherol; Antioxidants; Biphenyl Compounds; Butylated Hydroxyanisole; Butylated Hydroxytoluene; Chelating Agents; Dose-Response Relationship, Drug; Drug Evaluation, Preclinical; Ferrous Compounds; Ferrozine; Free Radical Scavengers; Hydrogen Peroxide; Linoleic Acid; Morphine; Picrates; Reducing Agents; Superoxide Dismutase

Antioxidant activities of extracts derived from sesame seed by supercritical carbon dioxide (SC-CO(2)) extraction and by n-hexane were determined using alpha,alpha-diphenyl-beta-picylhydrazyl (DPPH) radical scavenging and linoleic acid system methods. The highest extracted yield was given at 35 degrees C, 40 MPa, and a CO(2) flow rate of 2.5 mL min(-1) by an orthogonal experiment. The yields of extracts increased with increasing pressure, and yields at 40 and 30 MPa were higher than that by solvent extraction at 46.50%. Results from the linoleic acid system showed that the antioxidant activity follows the order: extract at 35 degrees C, 20 MPa > BHT > extract at 55 degrees C, 40 MPa > extract at 55 degrees C, 30 MPa > Trolox > solvent extraction > alpha-tocopherol. The SC-CO(2) extracts exhibited significantly higher antioxidant activities comparable to that by n-hexane extraction. The extracts at 30 MPa presented the highest antioxidant activities assessed in the DPPH method. At 20 MPa, the EC(50) increased with temperature, which indicated that the antioxidant activity was decreased in a temperature-dependent manner. The significant differences of antioxidant activities were found between the extracts by SC-CO(2) extraction and n-hexane. However, no significant differences were exhibited among the extracts by SC-CO(2) extraction. The vitamin E concentrations were also significantly higher in SC-CO(2) extracts than in n-hexane extracts, and its concentrations in extracts corresponded with the antioxidant activity of extracts.

Topics: Antioxidants; Biphenyl Compounds; Carbon Dioxide; Chromatography, Supercritical Fluid; Free Radical Scavengers; Linoleic Acid; Picrates; Plant Extracts; Seeds; Sesamum

This study was designed to examine the in vitro antimicrobial and antioxidant activities of the essential oil and various extracts obtained from aerial parts of Thymus eigii. The essential oil was particularly found to possess stronger antimicrobial activity, whereas other nonpolar extracts and subfractions showed moderate activity and polar extracts remained almost inactive. GC-MS analysis of the oil resulted in the identification of 39 compounds, representing 93.7% of the oil; thymol (30.6%), carvacrol (26.1%), and p-cymene (13.0%) were the main components. The samples were also subjected to a screening for their possible antioxidant activity by using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and beta-carotene-linoleic acid assays. In the former case, the polar subfraction of the methanol extract was found to be superior to all extracts tested, only 16.8 microg/mL of which provided 50% inhibition, whereas all extracts, particularly the polar ones, seem to inhibit the oxidation of linoleic acid in the latter case. These data were further supported by total phenolics analysis, indicating that the antioxidative potential of the extracts was closely related to their phenolic constituents.

Topics: Anti-Bacterial Agents; Antioxidants; beta Carotene; Biphenyl Compounds; Cymenes; Gas Chromatography-Mass Spectrometry; Lamiaceae; Linoleic Acid; Monoterpenes; Oils, Volatile; Oxidation-Reduction; Picrates; Plant Extracts; Plant Oils; Thymol

The antioxidant and antiradical activities of 5,7,3'-trihydroxy-3,6,4'-trimethoxyflavone or centaureidin isolated and characterized from Brickellia veronicaefolia were elucidated by heat-induced oxidation in a beta-carotene and linoleic acid system and by the 1,1-diphenyl-2-picrylhydrazyl decoloration test. The centaureidin (32.1%) exhibited antioxidative activity less than that of BHT (95.5%) and alpha-tocopherol (95.9%) on oxidation in a beta-carotene and linoleic acid system. A moderate antiradical effect (47.6%) compared with BHT (96.7%) and alpha-tocopherol (94.6%) in DPPH decoloration test was found.

Topics: Antioxidants; Asteraceae; beta Carotene; Biphenyl Compounds; Flavonoids; Free Radical Scavengers; Humans; Linoleic Acid; Phytotherapy; Picrates; Plant Extracts; Plant Leaves

A flavonoid-rich extract of Hypericum perforatum L. (FEHP) was prepared by adsorption on macroporous resin and desorption by ethanol. Total flavonoid content of FEHP was determined by a colorimetric method. The major constituents of FEHP, including rutin, hyperoside, isoquercitrin, avicularin, quercitrin, and quercetin, were determined by HPLC analysis and confirmed by LC-MS. Different antioxidant assays were utilized to evaluate free radical scavenging activity and antioxidant activity of FEHP. FEHP was an effective scavenger in quenching DPPH and superoxide radical with IC50 of 10.63 microg/mL and 54.3 microg/mL, respectively. A linear correlation between concentration of FEHP and reducing power was observed with a coefficient of r2 = 0.9991. Addition of 150 microg of FEHP obviously decreased the peroxidation of linoleic acid during 84 h incubation, but the amount of FEHP over 150 microg did not show statistically significant inhibitory effect of peroxidation of linoliec acid (p > 0.05). FEHP exhibited inhibitory effect of peroxidation of liposome induced both by hydroxyl radical generated with iron-ascorbic acid system and peroxyl radical and showed prominent inhibitory effect of deoxyribose degradation in a concentration-dependent manner in site-specific assay but poor effect in non-site-specific assay, which suggested that chelation of metal ion was the main antioxidant action. According to the results obtained in the present study, the antioxidant mechanism of FEHP might be attributed to its free radical scavenging activity, metal-chelation activity, and reactive oxygen quenching activity.

Topics: Antioxidants; Biphenyl Compounds; Chromatography, High Pressure Liquid; Deoxyribose; Flavonoids; Free Radical Scavengers; Hypericum; Kinetics; Linoleic Acid; Lipid Peroxidation; Oxidation-Reduction; Picrates; Plant Extracts; Superoxides

Propolis is a resinous substance collected by honeybees from various plant sources. The composition of propolis depends on time, vegetation, and the area of collection. This study examined the antioxidant activity of propolis from various areas of Korea: Chilgok, Cheongju, Geochang, Muju, Pocheon, and Sangju. Ethanol extracts of propolis (EEP) were prepared and evaluated for their antioxidant activity by beta-carotene bleaching, 1,1-diphenyl-2-picrylhydrazyl free radical scavenging, and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radical cation decolorization assays. Furthermore, the major constituents in EEP were identified by high-performance liquid chromatography analysis with a photodiode array and mass spectrometric detection, and each component was quantitatively analyzed. EEP from Cheongju and Muju had relatively strong antioxidant activity accompanied by high total polyphenol contents. Propolis from Cheongju contained large amounts of antioxidative compounds, such as caffeic acid, kaempferol, and phenethyl caffeate. On the other hand, propolis from Pocheon had compounds not seen in propolis from other areas.

Topics: Antioxidants; Benzothiazoles; Biphenyl Compounds; Chromatography, High Pressure Liquid; Ethanol; Flavonoids; Free Radical Scavengers; Korea; Linoleic Acid; Oxidation-Reduction; Phenols; Picrates; Plant Extracts; Polyphenols; Propolis; Sulfonic Acids

The stem and root of Porcelainberry (Ampelopsis brevipedunculata (Maxim.) Trautv.) (AB) was traditionally used as an anti-inflammatory, diuretic and anti-hepatotoxic agent in folk medicine. In this study, cell-free and cell culture systems were employed to investigate the antioxidant activity of the methanol extract of AB (MEAB). The cell-free system showed that the MEAB exhibited dose-dependent antioxidant activities against linoleic acid peroxidation and plasmid DNA oxidation. We also demonstrated that the MEAB possessed strong reducing power and scavenging effects of hydroxyl radicals and DPPH free radicals. The harmful effects of reactive oxygen metabolites on HepG2 cells and the possible antioxidant effects of the MEAB were also investigated. Pretreatment or cotreatment of HepG2 cells with the MEAB could significantly protect cells from H2O2-induced oxidative stress. This implies that the antioxidant effects in cell culture may result from the direct interaction between the MEAB and exogenous oxidant sources, as these occur in cell free systems, as well as from the induction of cellular stress gene expression. The antioxidant activity of the MEAB may partially explain its anti-inflammatory and anti-hepatotoxic effects.

Topics: Antioxidants; Biphenyl Compounds; Cell Line, Tumor; DNA, Neoplasm; Drugs, Chinese Herbal; Humans; Hydrazines; Linoleic Acid; Oxidation-Reduction; Oxidative Stress; Picrates; Plant Extracts; Plants, Medicinal

Water, aqueous methanol, and aqueous ethanol extracts of freeze-dried leaves of Moringa oleifera Lam. from different agroclimatic regions were examined for radical scavenging capacities and antioxidant activities. All leaf extracts were capable of scavenging peroxyl and superoxyl radicals. Similar scavenging activities for different solvent extracts of each collection were found for the stable 1,1-diphenyl 2-picrylhydrazyl (DPPH(*)) radical. Among the three different moringa samples, both methanol and ethanol extracts of Indian origins showed the highest antioxidant activities, 65.1 and 66.8%, respectively, in the beta-carotene-linoleic acid system. Nonetheless, increasing concentration of all the extracts had significantly (P < 0.05) increased reducing power, which may in part be responsible for their antioxidant activity. The major bioactive compounds of phenolics were found to be flavonoid groups such as quercetin and kaempferol. On the basis of the results obtained, moringa leaves are found to be a potential source of natural antioxidants due to their marked antioxidant activity. This is the first report on the antioxidant properties of the extracts from freeze-dried moringa leaves. Overall, both methanol (80%) and ethanol (70%) were found to be the best solvents for the extraction of antioxidant compounds from moringa leaves.

Topics: Adenosine Diphosphate; Antioxidants; Ascorbic Acid; beta Carotene; Biphenyl Compounds; Chromatography, High Pressure Liquid; Ferric Compounds; Flavonoids; Free Radical Scavengers; Hydrogen Peroxide; Linoleic Acid; Lipid Peroxidation; Moringa oleifera; NADP; Oxidation-Reduction; Phenols; Picrates; Plant Extracts; Plant Leaves; Reducing Agents; Solvents; Superoxides

Seven antioxidative compounds were isolated from the EtOAc extract of the aerial part of C. sessiliflora (Japanese name, tanukimame) by activity-guided fractionation with 2,2-diphenyl-1-picrylhydrazyl (DPPH). Among the isolated compounds, hydroxyeucomic acid showed the strongest free radical-scavenging activity, which was almost identical to that of epigallocatechin gallate, against DPPH. Orientin and isoorientin showed strong anti-peroxidative activities toward linoleic acid and protective effects against the bactericidal action of the tert-butyl peroxyl radical. Their activities were nearly equal to that of epigallocatechin gallate.

Topics: Antioxidants; Biphenyl Compounds; Catechin; Chemical Fractionation; Crotalaria; Free Radical Scavengers; Free Radicals; Hydrazines; Linoleic Acid; Lipid Peroxidation; Oxidation-Reduction; Picrates; Plant Components, Aerial; Plant Extracts; tert-Butylhydroperoxide

Radical scavenging activities of extracts and constituents in Cornus capitata adventitious root cultures were evaluated by using 1,1-diphenyl-2-pycrylhydrazyl (DPPH) and superoxide anion radicals. Inhibitory activity against peroxidation of linoleic acid was assayed by using the thiobarbituric acid (TBA) method. Ethyl acetate and aqueous fractions were prepared from adventitious roots cultured in Murashige-Skoog liquid medium with 0.1 microM Cu(2+) (0.1CuMS) or 10 microM Cu(2+) (10CuMS). The highest scavenging activities on DPPH and superoxide anion radicals were observed in the ethyl acetate fraction from 0.1CuMS. In the inhibitory activity against linoleic acid oxidation, the ethyl acetate fraction from 10CuMS was highest among the fractions tested. The ethyl acetate fraction of adventitious roots cultured in 0.1CuMS contained mainly galloylglucoses (1,2,3,6-tetragalloylglucose and 1,2,3,4,6-pentagalloylglucose). The ethyl acetate fraction of adventitious roots cultured in 10CuMS contained mainly ellagic acid derivatives [3,3'-di-O-methylellagic acid 4-(5"-acetyl)-alpha-L-arabinofuranoside and stenophyllin H1]. Aqueous fractions prepared from both media contained iridoid glycosides (dihydrocornin and cornin). Tetra- and pentagalloylglucoses showed strong inhibitory activities (61.9 and 85.2%, respectively) against linoleic acid oxidation relative to those of butylated hydroxytoluene (BHT) (91.1%) or alpha-tocopherol (49.5%) at 50 microM concentration. Although both ellagic acid derivatives had weak activities (<50%) on DPPH and superoxide anion radical scavenging, 3,3'-di-O-methylellagic acid 4-(5"-acetyl)-alpha-L-arabinofuranoside was stronger (74.7%) than alpha-tocopherol (49.5%) in inhibiting linoleic acid oxidation at 50 microM concentration. Iridoid glycosides exhibited little activity against DPPH and superoxide anion radicals or against oxidation of linoleic acid.

Topics: Acetates; Antioxidants; Biphenyl Compounds; Cornus; Free Radical Scavengers; Linoleic Acid; Lipid Peroxidation; Picrates; Plant Extracts; Plant Roots; Superoxides; Thiobarbituric Acid Reactive Substances

The polysaccharide and flavonoid concentrations of two-, three-, and four-year-old Aloe vera were determined, and their antioxidant activities were evaluated compared to BHT and alpha-tocopherol by the DPPH radical scavenging method and the linoleic acid system at 100 microg of soluble solids per mL of ethanol. The results showed that three-year-old Aloe vera contained significantly higher levels of polysaccharides and flavonoids than two- and four-year-old Aloe vera, and no significant differences in flavonoid levels were found between three- and four-year-old Aloe vera. All the aloe extracts showed significant antioxidant activity. The antioxidant activity of Aloe vera extracts and reference compounds followed the order: three-year-old Aloe vera > BHT > four-year-old Aloe vera > alpha-tocopherol > two-year-old Aloe vera. The three-year-old extract exhibited the strongest radical scavenging activity of 72.19%, which is significantly higher than that of BHT at 70.52% and alpha-tocopherol at 65.20%. These data suggest that the growth stage plays a vital role in the composition and antioxidant activity of Aloe vera.

Topics: Aloe; alpha-Tocopherol; Antioxidants; Biphenyl Compounds; Butylated Hydroxyanisole; Ethanol; Flavonoids; Free Radical Scavengers; Linoleic Acid; Picrates; Plant Extracts; Polysaccharides; Time Factors

An attempt to synthesize 6-hydroxypyridoxine (OPN), hydroxylation on C-6 of pyridoxine (PN) by hydroxyl radical (OH*). was conducted. Application of two well-known OH* generating reactions, i.e. the Fenton reaction and the Fe2+-EDTA/ascorbate reaction, were unsuccessful, as large amounts of by-products were formed. Although generation of OH* by autoxidation of ascorbic acid in the absence of metal ions was slow, by-products were formed in small quantities, and OPN was easily obtained in colorless crystals. Its structure was confirmed by spectral analyses. OPN was comparable to polyphenols such as (+)-catechin, rutin and gallic acid in the antioxidative activity against linoleic acid peroxidation, and was an effective DPPH radical scavenger, though the DPPH radical-scavenging activity of OPN was somewhat lower than that of the polyphenols. PN was relatively inactive under the conditions used here, indicating that the introduction of a hydroxyl group on C-6 of PN greatly enhanced both activities.

Topics: Antioxidants; Ascorbic Acid; Biphenyl Compounds; Crystallization; Edetic Acid; Ferrous Compounds; Flavonoids; Free Radical Scavengers; Hydroxyl Radical; Hydroxylation; Linoleic Acid; Oxidation-Reduction; Phenols; Picrates; Polyphenols; Pyridoxine

Both the pro- and antiradical water soluble activity, toward DPPH(*), ROO(*), OH(*) radicals found in seven diet vegetables belonging to the Cichorium genus, and the effects of boiling, freezing, and freeze-drying on such activities were investigated. The vegetables were three red cultivars of Cichorium intybus var. silvestre from three different areas of production, that is, chicory from Chioggia, Treviso, and Verona, C. intybus var. foliosum (Belgian chicory), C. endivia var. latifolium (escarole), C. endiviavar. crispum ("crispa"), and a hybrid vegetable obtained by the cross between C. intybus var. silvestre and C. endivia var. latifolium (chicory from Castelfranco). The juices obtained by simple centrifugation of vegetables operating at 2 or 25 degrees C and submitted to the thermal technological treatments were assessed for antiradical activity using the DPPH(*) assay, the linoleic acid-beta-carotene system, and the deoxyribose assay. In all three assays used, each vegetable juice was shown to possess antiradical activity; there was a significant level in the C. endivia and the Belgian chicories and higher levels in the red C. intybus vegetables and the hybrid vegetable. All juice behaviors in the linoleic acid-beta-carotene system indicate that they also contain a thermally unstable component, which in a cold medium promptly promoted and accelerated linoleic acid peroxidation, therefore masking the presence of any thermally stable antiperoxyl radical components. The presence of these components, which efficiently protect linoleic acid from peroxidation, can be singled out only after inactivation by heating, or separation by dialysis, of the pro-oxidant components. Dialysis fractions showed that the pro-oxidant component has MW > 50000 Da and that the juices contain a number of antioxidant components which contribute to their antiradical activity.

Topics: Antioxidants; beta Carotene; Beverages; Biphenyl Compounds; Cichorium intybus; Deoxyribose; Dialysis; Free Radicals; Freeze Drying; Freezing; Hot Temperature; Linoleic Acid; Oxidants; Picrates; Solubility; Water

Squalene was identified by gas chromatography-mass spectrometry and high-performance liquid chromatography (HPLC) spiking analyses in the supercritical CO(2) extracts of freeze-dried abscisic leaves of Terminalia catappa L. When the freeze-dried abscisic, senescent, mature, and immature leaves and seeds were subjected to supercritical CO(2) extraction at 40 degrees C and 3000 psi and HPLC quantitation, squalene contents were 12.29, 2.42, 1.75, 0.9, and 0% in the extracts and corresponding to 1499, 451, 210, 65, and 0 microg/g in the freeze-dried sample, respectively. When the extracts were applied for antioxidative characterization by supplementation in an iron/ascorbate system with linoleic acid and in a pork fat storage system for inhibition of conjugated diene hydroperoxide (CDHP) formation or in a free radical scavenging system with 1,1-diphenyl-2-picryl-hydrazyl (DPPH), the extracts of leaves exhibited potent antioxidative and DPPH scavenging activities and increased with an increase of leaf maturity. However, the seed extracts only exhibited potent inhibition of CDHP formation and very low DPPH scavenging activity.

Topics: Animals; Antioxidants; Ascorbic Acid; Biphenyl Compounds; Chromatography, High Pressure Liquid; Chromatography, Supercritical Fluid; Free Radical Scavengers; Freeze Drying; Gas Chromatography-Mass Spectrometry; Hydrogen Peroxide; Iron; Linoleic Acid; Lipid Peroxidation; Picrates; Plant Extracts; Plant Leaves; Seeds; Squalene; Swine; Terminalia

Beans were pearled to evaluate the feasibility of increasing antioxidant activity and phenolic antioxidants. Phenolics were concentrated mostly in the hull fraction at about 56 mg of catechin equivalents per gram of sample. The methanolic extracts of the pearled bean samples were screened for antioxidant potential using the beta-carotene-linoleate and the 1,1-diphenyl-2-picrylhydrazyl (DPPH) in vitro model systems. The pearled material, also referred to as milled samples, exhibited antioxidant activity that correlated with phenolic content and inhibited DPPH significantly in a dose-dependent manner. Phenolics and antioxidant activities were also examined in chromatographic fractions of methanolic extracts of manually obtained hulls that represented a model used previously to ascertain antimutagenic activity. Fractions extracted with ethyl acetate/acetone and acetone displayed antioxidant activity, which implies potent free radical scavenging activity with antimutagenic activity.

Topics: Acetates; Acetone; Antimutagenic Agents; Antioxidants; beta Carotene; Biphenyl Compounds; Free Radical Scavengers; Kinetics; Linoleic Acid; Methanol; Phaseolus; Phenols; Picrates; Plant Extracts; Seeds

The yam (Dioscorea batatas Decne) tuber mucilage (YTM) was extracted and partially purified by SDS and heating treatments. This purified YTM exhibited antioxidant activities in a series of in vitro tests, including 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical (half-inhibition concentration, IC 50, was 0.86 mg/mL) and hydroxyl radical (IC 50 was 22 microg/mL) scavenging activity assays, reducing power test, anti-lipid peroxidation and anti-human low density lipoprotein peroxidation tests (IC 50 was 145.46 microg/mL) using butylated hydroxytoluene (BHT), reduced glutathione, or ascorbic acid for comparisons. With electron paramagnetic resonance (EPR) spectrometry for DPPH radical detection, the intensities of the EPR signals were decreased by the increased amounts of YTM added (IC 50 was 1.62 mg/mL). These results suggest that mucilage of yam tuber might play roles as antiradicals and antioxidants.

Topics: Adhesives; Antioxidants; Biphenyl Compounds; Dioscorea; Dose-Response Relationship, Drug; Electron Spin Resonance Spectroscopy; Hydroxyl Radical; Linoleic Acid; Lipid Peroxidation; Oxidation-Reduction; Picrates; Plant Extracts; Plant Stems

Antioxidant activity of 24 ferulic acid related compounds together with 6 gallic acid related compounds was evaluated using several different physical systems as well as their radical scavenging activity. The radical scavenging activity on 1,1-diphenyl-2-picrylhydrazyl (DPPH) decreased in the order caffeic acid > sinapic acid > ferulic acid > ferulic acid esters > p-coumaric acid. In bulk methyl linoleate, test hydroxycinnamic acids and ferulic acid esters showed antioxidant activity in parallel with their radical scavenging activity. In an ethanol-buffer solution of linoleic acid, the activity of test compounds was not always associated with their radical scavenging activity. Ferulic acid was most effective among the tested phenolic acids. Esterification of ferulic acid resulted in increasing activity. The activity of alkyl ferulates was somewhat influenced by the chain length of alcohol moiety. When the inhibitory effects of alkyl ferulates against oxidation of liposome induced by AAPH were tested, hexyl, octyl, and 2-ethyl-1-hexyl ferulates were more active than the other alkyl ferulates. Furthermore, lauryl gallate is most effective among the tested alkyl gallates. These results indicated that not only the radical scavenging activity of antioxidants, but also their affinity with lipid substrates, might be important factors in their activity.

Topics: Antioxidants; Bepridil; Biphenyl Compounds; Buffers; Caffeic Acids; Coumaric Acids; Esterification; Ethanol; Free Radical Scavengers; Free Radicals; Gallic Acid; Hot Temperature; Linoleic Acid; Liposomes; Oryza; Picrates; Plant Structures; Solutions

Three tests of increasing complexity were used to assess the antioxidant activity of five synthetic gallic esters of sucrose bearing 3, 6, 7, or 8 galloyl units. In addition, two of these compounds had 1 or 2 hydrocarbon (C10-C12) acyl chains. Reaction with the DPPH radical led to the evaluation of the number of radicals trapped per galloyl unit n (3-4), as well as the apparent second-order rate constant for H atom donation k (1200-1500/M/s). These results indicated similar contribution and reactivity of all the galloyl units. Inhibition of the AAPH-initiated peroxidation of linoleic acid in a micellar medium confirmed the additive contribution of the galloyl units, whereas the presence of the hydrocarbon acyl chains had no influence. These results suggest an inhibition of initiation at high antioxidant levels and an underlying prooxidant effect of the galloyl radicals at low concentrations. Finally, LDL peroxidation was inhibited in proportion to the number of galloyl units, in agreement with the preceding tests.

Topics: Amidines; Biphenyl Compounds; Esters; Free Radical Scavengers; Free Radicals; Gallic Acid; Hydrolyzable Tannins; Linoleic Acid; Lipid Peroxidation; Lipoproteins, LDL; Oxidants; Picrates; Sucrose; Tannins

Conjugated linoleic acid (CLA) isomers were investigated for free radical scavenging properties against the stable 2,2-diphenyl-1-picryhydrazyl radical (DPPH(*)) by electron spin resonance (ESR) spectrometry and spectrophotometric methods. ESR measurements confirmed that both c9,t11-CLA and t10,c12-CLA directly reacted with and quenched DPPH radicals, whereas spectrophotometric analysis demonstrated that c9,t11-CLA and t10,c12-CLA differed in their kinetic and thermodynamic properties in reacting with DPPH radicals. t10,c12-CLA was shown to exhibit a greater initial velocity in CLA-DPPH radical reactions at levels of 2.5-80 mg/mL, and c9,t11-CLA scavenged more DPPH radicals at steady state. Similar dose and time relationships were observed for both isomers. In addition, a mixture of c9,t11- and t10,c12-CLA isomers demonstrated a greater initial velocity in quenching DPPH radicals than either isomer alone on the same concentration basis, suggesting that a synergistic effect between CLA isomers existed in their reactions with DPPH radicals. These results support the conclusion that individual CLA isomers differ in their biological actions and indicate that interaction(s) between isomers may contribute to their beneficial effects.

Topics: Antioxidants; Biphenyl Compounds; Body Fluids; Chromatography, Gas; Drug Interactions; Drug Synergism; Electron Spin Resonance Spectroscopy; Free Radical Scavengers; Free Radicals; Isomerism; Kinetics; Linoleic Acid; Picrates; Stomach; Structure-Activity Relationship; Thermodynamics

The aim of this paper was to clarify whether the interaction of the lazaroid U-74389G with phospholipid membranes might be relevant as to its antioxidant activity. Thus we evaluated the "in vitro" antioxidant activity of U-74389G in two experimental models: 1) bleaching of the stable 1,1-diphenyl-2-picrylhydrazyl radical; 2) peroxidation, induced by the water-soluble radical initiator 2,2'-azobis(2-amidino-propane) hydrochloride, on mixed dipalmitoyl-phosphatidylcholine/linoleic acid unilamellar vesicles. Moreover, given that biophysical techniques may help in explaining the role of a drug in its interaction with the microenvironment of the model lipid membranes, we used a classical approach to investigate the U-74389G/model membrane interaction: the differential scanning calorimetry technique on dimyristoylphosphatidylcholine multilamellar and unilamellar vesicles and the Langmuir-Blodgett technique on dimyristoylphosphatidylcholine monolayers. The results evidenced the strong antioxidant activity of U-74389G (especially in a membranous system) and its capability to interact with and be transported across model membranes. Thus one can speculate that U-74389G can act as scavenger of chain-propagating lipid peroxyl radicals within the membranes and may be able to protect not only cell membranes, but also intracellular components against peroxidative attack. Furthermore, also if there is no certain proof that the effect on the lipid packing order may play a key role in its antioxidant activity, the fluidifying effect on phospholipid bilayers of U-74389G favourably complements its free radical scavenging characteristics.

Topics: 1,2-Dipalmitoylphosphatidylcholine; Amidines; Antioxidants; Bepridil; Biphenyl Compounds; Calorimetry, Differential Scanning; Dexamethasone; Free Radical Scavengers; Free Radicals; In Vitro Techniques; Linoleic Acid; Lipid Bilayers; Lipid Peroxidation; Oxidation-Reduction; Picrates; Pregnatrienes

Fenretinide, N-(4-hydroxyphenyl)retinamide (4-HPR), is a cancer chemopreventive and antiproliferative agent whose mechanism of action is unknown. 4-HPR is a potent inducer of apoptosis in HL60 human leukemia cells which generates intracellular reactive oxygen species. The structural similarity of retinoic acid (RA), 4-HPR, and alpha-tocopherol (vitamin E) led us to investigate whether 4-HPR exhibits antioxidant activity. It was found that 4-HPR scavenged alpha,alpha-diphenyl-beta-picrylhydrazyl (DPPH) radicals in a 1:1 ratio in contrast to vitamin E, where a 1:2 ratio relative to DPPH radicals was observed. In addition, linoleic acid peroxidation initiated by hydroxyl radicals was decreased by 4-HPR to the same extent as by vitamin E. Furthermore, lipid peroxidation in rat liver microsomes was reduced by 4-HPR to a greater extent than by vitamin E. Based on these results, 4-HPR appears to be an effective antioxidant that may have clinical utility for diseases treated with vitamin E.

Topics: Animals; Antineoplastic Agents; Antioxidants; Ascorbic Acid; Bepridil; Biphenyl Compounds; Fenretinide; Free Radical Scavengers; Free Radicals; Humans; Hydroxyl Radical; In Vitro Techniques; Linoleic Acid; Lipid Peroxidation; Male; Microsomes, Liver; Picrates; Rats; Rats, Sprague-Dawley; Reactive Oxygen Species; Retinoids; Vitamin E

Diaryl tellurides were found efficiently to retard azo-initiated lipid peroxidation of linoleic acid in methanol. The most efficient compounds, 31 and 39, contained one and two hydroxyl groups, respectively, in the para positions and methyl groups in all four positions ortho to tellurium. As determined by the values of n.kinh, these materials were as effective retarders of lipid peroxidation as vitamin E. Contrary to the conventional antioxidants examined, diaryl tellurides were found to inhibit peroxidation for long times, seemingly with an autocatalytic mechanism. Diaryl tellurides were found to be partially oxidized during the peroxidation. The reduction of tellurium (IV) compounds to the divalent state during the conditions of the experiment is discussed. The reactivity of some diaryl chalcogenides toward 2,2-diphenyl-1-picrylhydrazyl (DPPH) in methanol was studied. All compounds investigated were less reactive than vitamin E. One of the most active organotellurium compounds, bis(4-aminophenyl) telluride, reacted considerably faster with DPPH than the corresponding selenide or sulfide. It was concluded that mechanisms involving both hydrogen atom transfer and electron transfer were operative in the reaction of organotellurides with DPPH.

Topics: Antioxidants; Bepridil; Biphenyl Compounds; Linoleic Acid; Linoleic Acids; Lipid Peroxidation; Methanol; Molecular Structure; Organometallic Compounds; Picrates; Structure-Activity Relationship; Vitamin E