iridoids and 1-1-diphenyl-2-picrylhydrazyl

The aim of the study was to identify new potential chemical markers of extra virgin olive oil (EVOO) quality by using a multicomponent analysis approach. Sixty-six EVOOs were purchased from the Italian market and classified according to their price as low price EVOOs (LEVOOs) and high price EVOOs (HEVOOs) costing 3.60-5.90euro/L and 7.49-29.80euro/L respectively. Sensory and chemical parameters strictly related to olive oil quality have been investigated, like volatile substances, polar phenolic substances, antioxidant activity, fatty acid composition, and α-tocopherol. Significant differences in terms of chemical composition and sensory features have been highlighted between the two EVOOs classes investigated, proving a generally lower level of quality of LEVOOs, clearly showed also by means of principal component analysis. Among the most interesting outcomes, R ratio (free tyrosol and hydroxytyrosol over total free and bound forms), measuring the extent of secoiridoids hydrolysis, resulted to be significantly higher in LEVOOs than in HEVOOs. Other key differences were found in the volatile substances composition, in the stearic acid percentage and in p-coumaric acid content.

Topics: Aldehydes; alpha-Tocopherol; Antioxidants; Biphenyl Compounds; Coumaric Acids; Fatty Acids; Food Quality; Humans; Iridoids; Italy; Olea; Olive Oil; Phenols; Picrates; Polyphenols; Stearic Acids; Tocopherols

This study was aimed to investigate antioxidation and α-glucosidase inhibition of the bioactive compounds in three cultivars of blueberry ('Northland' (NL) from the hybrid blueberry (V. corymbosum L.×V. angustifolium Aiton), 'Britewell' (BW), and 'Gardenblue' (GB) from the rabbiteye blueberry (Vaccinium ashei Reade)). A total of eighteen anthocyanins were identified and quantified in Anthocyanins (ACNs), among which four acylated anthocyanins were exclusively found in Northland. The blueberry anthocyanin extracts (BAEs) were further measured the antioxidant activity and α-glucosidase inhibition effect. Northland BAEs exhibited significantly superior antioxidant activity compared with BAEs of other cultivars, and the antioxidant activity was correlated with the content of anthocyanins. However, α-glucosidase inhibition test showed that Britewell BAEs had the strongest inhibitory effect. BAEs were further separated into anthocyanin fraction (AF) and copigment fraction (CF). Fifteen phenolic acids and four iridoids were identified in CF. In terms of α-glucosidase inhibition effects, the CF from three cultivars could inhibit α-glucosidase in a dose-dependent manner, while the AF did not show significant inhibitory effects. The blueberry exhibits excellent antioxidant activity and α-glucosidase inhibition.

Topics: Anthocyanins; Antioxidants; Biphenyl Compounds; Blueberry Plants; Chromatography, High Pressure Liquid; Glycoside Hydrolase Inhibitors; Iridoids; Picrates; Plant Extracts; Tandem Mass Spectrometry

Hwangryunhaedok-tang (HHT) is a traditional herbal medicine that is used for the treatment of fever, inflammation, gastritis, and hypertension. In this study, we performed simultaneous determination of the five components, geniposide (1), baicalin (2), coptisine (3), palmatine (4), and berberine (5) in HHT by using a high-performance liquid chromatography-photodiode array (HPLC-PDA) analysis. We also evaluated the antioxidative activity of HHT and compounds 1-5 by measuring their effects on low-density lipoprotein (LDL) oxidation and antiproliferative abilities in vascular smooth muscle cells (VSMCs).. Five compounds were separated within 40 min by using a Gemini C18 column (temp. 35°C; two-component gradient elution; flow rate 1.0 mL/min; detector 240 and 277 nm). The activities of HHT and compounds 1-5 were tested with the radical scavengers 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt and 2,2-diphenyl-1-picrylhydrazyl, in thiobarbituric acid reactive substance assays, and in relative electrophoretic mobility assays using CuSO4-induced LDL oxidation systems. The antiproliferative effects of samples on platelet-derived growth factor (PDGF)-induced VSMC proliferation were studied by using a cell proliferation assay.. Regression analysis of the five major compounds showed good linearity (r (2) ≥ 0.9997) in different concentration ranges. The recoveries of the five compounds were in the range 86.31-110.78%, with relative standard deviations below 2.1%; those of intra- and interday precision were 0.04-3.78% and 0.04-1.69%, respectively. HHT reduced the oxidation properties of LDL induced by CuSO4 and inhibited cell proliferation in PDGF-treated VSMCs. Among the five components, compound 2 could effectively suppress LDL oxidation and PDGF-induced VSMC proliferation.. The established HPLC-PDA method will help to improve quality control of HHT. The results demonstrate that HHT has antiatherosclerotic activity and that it functions by modulating LDL oxidation and VSMC proliferation. The effects of HHT may be attributed, at least I part, to compound 2.

Topics: Animals; Antioxidants; Atherosclerosis; Berberine; Berberine Alkaloids; Biphenyl Compounds; Cell Proliferation; Chromatography, High Pressure Liquid; Coptis; Drugs, Chinese Herbal; Flavonoids; Gardenia; Iridoids; Lipoproteins, LDL; Medicine, Korean Traditional; Muscle, Smooth, Vascular; Phellodendron; Phytotherapy; Picrates; Platelet-Derived Growth Factor; Rats; Regression Analysis; Scutellaria

Genipin, the multipotent ingredient in Gardenia jasmenoides fruit extract (GFE), may be an effective candidate for treatment following stroke or traumatic brain injury (TBI). Secondary injury includes damage mediated by reactive oxygen species (ROS) and reactive nitrogen species (RNS), which can alter the biological function of key cellular structures and eventually lead to cell death. In this work, we studied the neuroprotective potential of genipin against damage stemming from ROS and RNS production in organotypic hippocampal slice cultures (OHSC), as well as its potential as a direct free radical scavenger. A 50 µM dose of genipin provided significant protection against tert-butyl hydroperoxide (tBHP), a damaging organic peroxide. This dosage of genipin significantly reduced cell death at 48 h compared to vehicle control (0.1% DMSO) when administered 0, 1, 6, and 24 h after addition of tBHP. Similarly, genipin significantly reduced cell death at 48 h when administered 0, 1, 2, and 6h after addition of rotenone, which generates reactive oxygen species via a more physiologically relevant mechanism. Furthermore, genipin significantly reduced both cell death and nitrite levels at 24 h caused by S-nitroso-N-acetylpenicillamine (SNAP), a direct nitric oxide (NO) donor, and successfully quenched 1,1-Diphenyl-2-picryl-hydrazyl (DPPH), a stable free radical, suggesting that genipin may act as a direct free radical scavenger. Our encouraging findings suggest that genipin should be tested in animal models of CNS injury with a significant component of ROS- and RNS-mediated damage, such as TBI and stroke, to assess its in vivo efficacy.

Topics: Analysis of Variance; Animals; Animals, Newborn; Ascorbic Acid; Biphenyl Compounds; Cell Death; Dose-Response Relationship, Drug; Hippocampus; Insecticides; Iridoids; Neuroprotective Agents; Nitric Oxide Donors; Organ Culture Techniques; Picrates; Reactive Nitrogen Species; Reactive Oxygen Species; Rotenone; S-Nitroso-N-Acetylpenicillamine; Time Factors

The crude extract of Swertia chirayita, an important medicinal plant of Nepal, is locally used for many diseases including type 2 diabetes. In this study, crude aqueous and 12% ethanol solution extracts of S. chirayita collected from nine districts of Nepal were analyzed for anti-diabetic-linked anti-hyperglycemia potential using in vitro biochemical assays. There was moderate-to-high positive correlation between antioxidant activity and total phenolic content of both extracts and moderate-to-high α-glucosidase inhibitory activity. Although the anti-diabetic property of S. chirayita is mainly attributed to the phytochemical swerchirin present in its hexane fraction, we propose that the crude extract of this plant used in local healing also has anti-hyperglycemia potential. The crude extracts indicated the presence of three main phytochemicals mainly mangiferin, swertiamarin, and amarogentin and their derivatives. Among the standard compounds (mangiferin, swertiamarin, and amarogentin), mangiferin showed α-glucosidase and 2,2-diphenyl-1-picrylhydrazyl radical inhibitory activity indicating anti-hyperglycemia potential.

Topics: Angiotensin-Converting Enzyme Inhibitors; Antioxidants; Biphenyl Compounds; Chromatography, High Pressure Liquid; Glycoside Hydrolase Inhibitors; Hypoglycemic Agents; Inhibitory Concentration 50; Iridoids; Nepal; Phenols; Picrates; Plant Extracts; Swertia; Xanthones

The roots of Nardostachys jatamansi have been used as a substitute for valerian in Iranian traditions. Moreover, six species from Valeriana genus such as V. sisymbriifolia grow in Iran which has not been studied yet. We aimed to study of antioxidant effect of Valeriana officinalis, Nardostachys jatamansi and Valeriana sisymbriifolia and comparing their content of valerenic acid and valepotriate. Antioxidant effect was evaluated using diphenylpicrylhydrazyl (DPPH) inhibition and beta carotene-bleaching assays. Identification of valepotriates was achieved using chemical and TLC method. Qualitative and quantitative analysis of valerenic acid was performed using TLC and spectrophotometry methods. Among the tested samples, V. Officinalis showed the highest DPPH inhibition effect with IC(50) value of 38mg/mL. All of the tested plants potentially inhibited beta-carotene oxidation. The calibration curve of authentic valerenic acid was linear in the range of 2-51 mg L(-1). The most and least amount of valepotraites was detectable in V. officinalis and V. sisymbriifolia respectively. Total valerenic acid in different plant species ranged from 0.02% in V. sisymbriifolia to 0.07% (w/w) in V. Officinalis. Our results indicated that all three tested plants contain different amount of valepotriates and valerenic acid. The highest percentage of valepotriates and valerenic acid was detectable in V. officinalis. Overall can conclude that N. jatamansii and V. sisymbriifolia would be a good candidate for substitutation of V. officinalis with noticeable antioxidant effect.

Topics: Antioxidants; beta Carotene; Biphenyl Compounds; Calibration; Chromatography, Thin Layer; Indenes; Iridoids; Linear Models; Nardostachys; Oxidation-Reduction; Picrates; Plant Extracts; Plant Roots; Plants, Medicinal; Reference Standards; Rhizome; Sesquiterpenes; Spectrophotometry, Ultraviolet; Valerian

Parkinson disease (PD) is the most common progressive neurodegenerative disorder characterized by progressive death of midbrain dopaminergic neurons. Most neurodegenerative disease treatments are, at present, palliative. However, some natural herbal products have been shown to rescue neurons from death and apoptosis in some of neurodegenerative diseases. Not only Olea europaea L. olive oil, but also the leaves of this plant have been used for medical purposes. Olive leaf extract (OLE) is being used by people as a drink across the world and as an integral ingredient in their desire to maintain and improve their health. Here, we investigated the effects of OLE and its main phenolic component oleuropein on 6-hydroxydopamine (6-OHDA)-induced toxicity in rat adrenal pheochromocytoma (PC12) cells as an in vitro model of PD. Cell damage was induced by 150 μM 6-OHDA. The cell survival rate was examined by MTT assay. Generation of intra-cellular reactive oxygen species (ROS) was studied using fluorescence spectrophotometry. Immunoblotting and DNA analysis were also employed to determine the levels of biochemical markers of apoptosis in the cells. The data showed that 6-OHDA could decrease the viability of the cells. In addition, intra-cellular ROS, activated caspase 3, Bax/Bcl-2 ratio, as well as DNA fragmentation were significantly increased in 6-OHDA-treated cells. Incubation of cells with OLE (400 and 600 μg/mL) and oleuropein (20 and 25 μg/mL) could decrease cell damage and reduce biochemical markers of cell death. The results suggest that OLE and oleuropein have anti-oxidant protective effects against 6-OHDA-induced PC12 cell damage. The protective effects of OLE and oleuropein are correlative with their anti-oxidative and anti-apoptotic properties and suggest their therapeutic potential in the treatment of PD.

Topics: Animals; Antioxidants; Apoptosis; bcl-2-Associated X Protein; Biphenyl Compounds; Caspase 3; Cell Survival; DNA Fragmentation; Enzyme Activation; Free Radical Scavengers; Intracellular Space; Iridoid Glucosides; Iridoids; Olea; Oxidopamine; PC12 Cells; Picrates; Plant Extracts; Plant Leaves; Protective Agents; Pyrans; Rats; Reactive Oxygen Species

The essential oil composition of the aerial parts of Nepeta erecta Benth. (Family: Lamiaceae) from Uttarakhand, India was analysed by capillary gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). A total of 34 constituents were identified representing 94.6% of the oil composition. Oxygenated monoterpenes (74.0%) constituted the major proportion of the oil, dominated by isoiridomyrmecin (70.6%) as a single major constituent. Other significant constituents were caryophyllene oxide (9.6%), β-Bourbonene (2.0%), humulene epoxide II (1.7%) and linalool (1.0%). The in vitro antioxidant activity (AOA) was assessed using β-Carotene bleaching assay, reducing power, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and inhibition of lipid peroxidation methods. The oil was found to exhibit AOA by inhibiting β-Carotene bleaching (54.6 ± 2.52%) and by scavenging DPPH free radical (IC(50) = 0.74 ± 0.12 mg mL(-1)). The AOA of the essential oil of N. erecta and its major compound isoiridomyrmecin has not been reported so far.

Topics: Acyclic Monoterpenes; Antioxidants; Biphenyl Compounds; Chromatography, Gas; Gas Chromatography-Mass Spectrometry; India; Iridoids; Molecular Structure; Monoterpenes; Nepeta; Oils, Volatile; Picrates; Polycyclic Sesquiterpenes; Sesquiterpenes

Leucosidea sericea is an important medicinal plant widely used in traditional medicine in southern Africa. Leaf and stem petroleum ether (PE), dichloromethane (DCM) and 50% aqueous methanol (MeOH) extracts were investigated for antioxidant and acetylcholinesterase inhibitory activities. The safety of the extracts was evaluated using the Ames test. In addition, the iridoid content of L. sericea stems and leaves were quantified. For DPPH radical-scavenging activity, the stem MeOH extract (EC(50) value: 1.6 μg/ml) was more potent than ascorbic acid (EC(50) value: 1.7 μg/ml). In the β-carotene-linoleic acid model system, antioxidant activity of the leaf DCM extract (89.8%) was not significantly different to that of butylated hydroxytoluene (BHT) (98.9%). All extracts showed a dose-dependent acetylcholinesterase inhibition; in terms of the IC(50) value, the leaf DCM extract (0.14 mg/ml) was the most potent sample. Total iridoid content was 35% higher in the stem extract than in the leaf extract. Based on the Ames test, L. sericea extracts were not mutagenic, either with or without S9 metabolic activation. These findings suggest the safety as well as the potential of L. sericea as a possible source of novel/alternative antioxidant and acetylcholinesterase inhibitory compounds.

Topics: Analysis of Variance; Antioxidants; Ascorbic Acid; Biphenyl Compounds; Cholinesterase Inhibitors; Drug-Related Side Effects and Adverse Reactions; Iridoids; Medicine, African Traditional; Mutagens; Picrates; Plant Extracts; Plant Leaves; Plant Stems; Plants, Medicinal; Rosaceae

The genus Veronica L. (Plantaginaceae) is represented by 79 species, 26 of which are endemic in Turkey. Some Veronica species are used for the treatment of different inflammatory diseases and cancer in traditional medicine. In addition, chemotaxonomy of the genus is important for the reclassification of the family Plantaginaceae after different phylogenetic studies.. Veronica cuneifolia subsp. cuneifolia D. Don and V. cymbalaria Bodard were studied from the view point of iridoid glucosides which are known as chemotaxonomical markers for this genus. Radical scavenging and cytotoxic activities of the extracts were also determined in this study.. Major compounds, isolated from iridoid fractions of V. cuneifolia subsp. cuneifolia were used as the standard compounds for HPLC after determination of their structures, and investigated for their presence in iridoid fractions of V. cymbalaria. Additionally, 2,2-diphenyl-1-picrylhydrazyl (DPPH) and SO radical scavenging and cytotoxic activities against three cancer and a noncancerous cell lines of both extract were also tested using the MTT method.. While aucubin, catalpol, verproside, amphicoside, verminoside, and veronicoside were obtained from V. cuneifolia subsp. cuneifolia, two more iridoid glucosides, 6-O-veratroylcatalposide and 6-O-isovanilloylcatalpol, were isolated from V. cymbalaria. Comparing both species, V. cuneifolia subsp. cuneifolia showed stronger radical scavenging and cytotoxic activities than V. cymbalaria.. Our results demonstrated that the iridoid contents of both species were very close to each other confirming to the chemotaxonomic studies on Veronica species and their different bioactivity range make the plants interesting from the view point of natural drug discovery research.

Topics: Animals; Antineoplastic Agents, Phytogenic; Biphenyl Compounds; Cell Proliferation; Chlorocebus aethiops; Chromatography, High Pressure Liquid; Dose-Response Relationship, Drug; Free Radical Scavengers; Hep G2 Cells; Humans; Inhibitory Concentration 50; Iridoids; Magnetic Resonance Spectroscopy; Mice; Molecular Structure; Picrates; Plant Components, Aerial; Plant Extracts; Plants, Medicinal; Vero Cells; Veronica

The major components of gardenia fruits are geniposide and water soluble pigment crocins. In this study, we investigate crocins and geniposide profiles of gardenia fruits from different cultivars and at the various stages of maturation. DPPH scavenging activity of gardenia fruits from different cultivars and at the various stages of fruit maturation was also assayed. Quantitative determination of crocins in the gardenia at the various stages of maturation revealed a significant increase when ripening. However, geniposide content was negatively correlated with ripening stages. A significant difference was observed when comparing crocin content of different gardenia from various cultivars and geniposide content also showed marked variety. Current study indicated no relationship between crocin and geniposide content in gardenia fruits at the various stages of maturation and DPPH radical scavenging activity. Data showed that, although crocins feature markedly less DPPH scavenging activity than gardenia ethanol extract, total crocin content of gardenias collected in various cultivars correlate, to a certain degree, with radical scavenging effects of the Chinese traditional medicine (r=0.75).

Topics: Antioxidants; Biphenyl Compounds; Carotenoids; Free Radical Scavengers; Fruit; Gardenia; Genotype; Iridoids; Molecular Structure; Picrates; Plant Extracts

From Veronica longifolia were isolated three chlorinated iridoid glucosides, namely, asystasioside E (6) and its 6-O-esters 6a and 6b, named longifoliosides A and B, respectively. The structures of 6a and 6b were proved by analysis of their spectroscopic data and by conversion to the catalpol ester verproside (5a) or to catalpol (5), respectively. The configuration of the previously known vanilloyl analogue, urphoside B, was shown to be the 6β-epimer (6c) of the structure originally reported. Longifoliosides A (6a) and B (6b) were found to exhibit radical-scavenging activity against nitric oxide, superoxide, and 2,2-diphenyl-1-picrylhydrazyl radicals.

Topics: Antioxidants; Biphenyl Compounds; Esters; Germany; Glucosides; Hydrocarbons, Chlorinated; Iridoids; Molecular Structure; Nitric Oxide; Picrates; Superoxides; Veronica

The neurosedative and antioxidative properties of some major compounds isolated from a citral chemotype of Lippia alba were investigated. Binding assays were performed on two CNS inhibitory targets: benzodiazepine and GABA(A) receptors. The most active compound was luteolin-7-diglucuronide, with half maximal inhibitory concentrations (IC(50)) of 101 and 40 microm, respectively. Fifteen compounds isolated from Lippia alba were tested for their radical scavenging capacities against DPPH. Four of the major compounds (verbascoside, calceolarioside E, luteolin-7-diglucuronide and theveside) were also tested for their antioxidant activity against superoxide radical-anion in cell-free (hypoxanthine-xanthine oxidase) and cellular (PMA-stimulated neutrophil granulocytes) systems.

Topics: Antioxidants; Binding, Competitive; Biphenyl Compounds; Female; Flavonoids; Free Radical Scavengers; Humans; Hydrazines; Hypnotics and Sedatives; Iridoids; Lippia; Male; Molecular Structure; Neutrophils; Oxidation-Reduction; Phenols; Picrates; Plant Extracts; Polyphenols; Reactive Oxygen Species; Receptors, GABA-A

Two new phenyldihydronaphthalene-type lignan glucosides, vitecannasides A (1) and B (2) were isolated from the fruit of Vitex cannabifolia Sieb. et. Zucc. (Verbenaceae) along with the six known lignan derivatives (3-8), four known iridoid glucosides (9-12), three known flavonoids (13-15), and one known phenylbutanone glucoside (16). Their chemical structures were determined on the basis of spectroscopic data as well as chemical evidence. The scavenging effect of 1, 2, and 11-16 on the stable free radical 1,1-diphenyl-2-picrylhydrazyl was examined. Compounds 1, 2, 14, and 15 exhibited stronger activity than that of L: -cysteine. Especially, 14 and 15 showed more potent activity than that of alpha-tocopherol.

Topics: alpha-Tocopherol; Biphenyl Compounds; Cysteine; Flavonoids; Free Radical Scavengers; Fruit; Glucosides; Iridoids; Lignans; Magnetic Resonance Spectroscopy; Molecular Structure; Picrates; Vitex

The seeds and the pulp of Gardenia volkensii yielded one new iridiod, namely 4-(2N-gardenamide)n-butanoic acid, together with the known iridoids genipin and genipin gentiobioside, the pterocarpin medicarpin, coumarins, phenylpropanoids, benzenoids and triterpenes. The structures of these were determined on the basis of spectroscopic data and by comparison of obtained data with those from literature. The fruit extracts of this plant exhibited moderate radical scavenging activity against DPPH radical and moderate lethality against brine shrimps (Artemia salina).

Topics: Animals; Artemia; Biphenyl Compounds; Butyrates; Butyric Acid; Chromatography, Thin Layer; Dose-Response Relationship, Drug; Free Radical Scavengers; Gardenia; Hydrazines; Iridoid Glycosides; Iridoids; Magnetic Resonance Spectroscopy; Molecular Structure; Picrates; Plant Extracts; Pyridones; Seeds

The antioxidant effects of two major secoiridoid glucosides (nuezhenoside and G13, separated in our laboratory) from Fructus Ligustri Lucidi had already been assayed though DPPH radicals, respectively. The results revealed that these ingredients showed significant antioxidant activities. A positive correlation existed between total content and antioxidant activity. G13 had shown higher antioxidant activity than nuezhenoside. It implied that the structure of secoiridoid glucoside was postitive to antioxidant activity. Otherwise, the results could promote the deep research of Furctus Ligustri Lucidi on antioxidant mechanism.

Topics: Antioxidants; Biphenyl Compounds; Free Radical Scavengers; Free Radicals; Fruit; Glucosides; Iridoids; Ligustrum; Molecular Structure; Picrates; Plants, Medicinal

Rapid production of reactive oxygen species (ROS) and upregulation of beta2 integrin by leucocytes are two important inflammatory responses in human leucocytes. To evaluate whether three phenylpropanoid glycosides (acteoside, crenatoside, and rossicaside B) and two iridoid glucosides (boschnaloside and 8-epideoxyloganic acid) identified from two medicinal plants with similar indications (Orobanche caerulescens and Boschniakia rossica) exhibited anti-inflammatory activity, their effects on N-formyl-methionyl-leucyl-phenylalanine (fMLP) and phorbol-12-myristate-13-acetate (PMA)-activated peripheral human neutrophils (PMNs) and mononuclear cells were examined. Pretreatment with 1-50 microM phenylpropanoid glycoside concentration-dependently diminished PMA- and fMLP-induced ROS production with IC50 values of approximately 6.8-23.9 and 3.0-8.8 muM, respectively. Iridoid glucoside was less effective than phenylpropanoid glycoside with an IC50 value of approximately 8.9-28.4 microM in PMA-activated PMNs and 19.1-21.1 microM in fMLP-activated mononuclear cells. Phenylpropanoid glycosides also effectively inhibited NADPH oxidase (NOX) and displayed potent free radical-scavenging activity, but did not interfere with pan-protein kinase C (PKC) activity. Furthermore, all compounds, except rossicaside B, significantly inhibited PMA- and fMLP-induced Mac-1 (a beta2 integrin) upregulation at 50 microM but not that of fMLP-induced intracellular calcium mobilization. These drugs had no significant cytotoxicity as compared with the vehicle control. Our data suggested that inhibition of ROS production, possibly through modulation of NOX activity and/or the radical scavenging effect, and beta2 integrin expression in leucocytes indicated that these compounds had the potential to serve as anti-inflammatory agents during oxidative stress.

Topics: Anti-Inflammatory Agents, Non-Steroidal; Biphenyl Compounds; Caffeic Acids; CD18 Antigens; Cells, Cultured; Free Radicals; Glucosides; Humans; Hydrazines; Iridoids; Leukocytes, Mononuclear; Macrophage-1 Antigen; N-Formylmethionine Leucyl-Phenylalanine; NADPH Oxidases; Neutrophils; Phenols; Picrates; Protein Kinase C; Reactive Oxygen Species; Tetradecanoylphorbol Acetate

From the hydromethanolic extract of the aerial parts of Globularia alypum grown in Morocco, a new chlorinated iridoid glucoside, globularioside has been isolated beside 5 known iridoid glycosides, globularin, globularicisin, globularidin, globularinin and globularimin. This is the first report of a chlorinated iridoid in G. alypum and in the Globulareaceae. Unlike all other known 7-chlorinated iridoid glucosides where the chlorine atom exhibits an alpha configuration, globularioside incorporate the chlorine atom as a 7beta substituent. The structures of the isolated compounds were established on the basis of ESI-MS, MS-MS, 1D and 2D NMR spectral analysis.

Topics: Antioxidants; Biphenyl Compounds; Carbohydrate Sequence; Chromatography, Liquid; Free Radicals; Glucosides; Iridoids; Magnetic Resonance Spectroscopy; Mass Spectrometry; Molecular Sequence Data; Picrates; Plant Extracts; Scrophulariaceae; Spectrometry, Mass, Electrospray Ionization; Spectrophotometry, Ultraviolet; Spectroscopy, Fourier Transform Infrared

Increasing interest in phenolic compounds in olives is due to their antioxidant and health-enhancing properties. In this study the phenolics in fruits of the Tunisian olive cultivar Chemlali were extracted by methanol-water and fractionated using Sephadex LH-20 column chromatography. The identification of phenolic monomers and flavonoids was based on separation by high-performance liquid chromatography equipped with a diode array detector followed by liquid chromatography-mass spectrometry and gas chromatography-mass spectrometry analysis. Oleuropein, a secoiridoid glycoside esterified with a phenolic acid, was the major compound. Eight phenolic monomers and 12 flavonoids were also identified in Chemlali olives. Five flavonoids were isolated and purified using Sephadex LH-20 column chromatography and preparative paper chromatography. The antioxidant activity of the extract and the purified compounds was evaluated by measuring the radical scavenging effect on 1,1-diphenyl-2-picrylhydrazyl and by using the beta-carotene-linoleate model assay. Acid hydrolysis of the extract enhanced its antioxidant activity. Hydroxytyrosol and quercetin showed antioxidant activities similar to that of 2,6-di-tert-butyl-4-methylphenol. A hydroxyl group at the ortho position at 3' on the B ring of the flavonoid nucleus could contribute to the antioxidant activity of the flavonoids.

Topics: Antioxidants; beta Carotene; Biphenyl Compounds; Chromatography, High Pressure Liquid; Flavonoids; Fruit; Gas Chromatography-Mass Spectrometry; Iridoid Glucosides; Iridoids; Molecular Weight; Olea; Phenols; Picrates; Pyrans; Tunisia

Antioxidative activities of methanol extracts from five Plantago species (P. afra, P. coronopus, P. lagopus, P. lanceolata, and P. serraria) were characterized by the DPPH scavenging test and the inhibition of Fe2+/ascorbate-induced lipid peroxidation on bovine brain liposomes. All extracts showed antioxidant activity in both methods. Whereas P. serraria exhibited the strongest activity as a DPPH scavenger, P. lanceolata and P. serraria were found to be the most active in the lipid peroxidation inhibition assay. The extracts were investigated regarding their composition by different colorimetric techniques, such as the content of total phenolic compounds by the Folin-Ciocalteu assay, flavonoids by AlCl3 reagent, phenylpropanoid glycosides (PPGs) by Arnow reagent, and iridoids by Trim-Hill assay. A high correlation was found between the scavenging potency and the total phenolic and phenylpropanoid content of the extracts but not between the lipid peroxidation potency and the extract composition. P. serraria is presented as a possible new source of natural antioxidants.

Topics: Antioxidants; Biphenyl Compounds; Colorimetry; Flavonoids; Free Radical Scavengers; Glycosides; Iridoids; Methanol; Phenols; Picrates; Plant Extracts; Plantago

Purification of a n-BuOH-soluble partition of the MeOH extract of Morinda citrifolia (Noni) fruits led to the isolation of two new iridoid glucosides, 6alpha-hydroxyadoxoside (1) and 6beta,7beta-epoxy-8-epi-splendoside (2), as well as 17 known compounds, americanin A (3), narcissoside (4), asperuloside, asperulosidic acid, borreriagenin, citrifolinin B epimer a, citrifolinin B epimer b, cytidine, deacetylasperuloside, dehydromethoxygaertneroside, epi-dihydrocornin, d-glucose, d-mannitol, methyl alpha-d-fructofuranoside, methyl beta-d-fructofuranoside, nicotifloroside, and beta-sitosterol 3-O-beta-d-glucopyranoside. The structures of the new compounds were determined by spectroscopic data interpretation. Compound 4, borreriagenin, cytidine, deacetylasperuloside, dehydromethoxygaertneroside, epi-dihydrocornin, methyl alpha-d-fructofuranoside, and methyl beta-d-fructofuranoside were isolated for the first time from M. citrifolia. The antioxidant activity was evaluated for all isolates in terms of both DPPH and ONOO(-) bioassays. The neolignan, americanin A (3), was found to be a potent antioxidant in these assays.

Topics: Antioxidants; Biphenyl Compounds; Cyclopentane Monoterpenes; Dioxins; Fruit; Glucosides; Iridoids; Molecular Structure; Morinda; Picrates; Plants, Medicinal; Pyrans

Two new iridoid glucosides of 10-O-caffeoyl scandoside methyl ester (3), and 6-methoxy scandoside methyl ester (4) besides the known compounds of scandoside methyl ester (1), methyl deacetyl asperulosidate (2), 10-O-caffeoyl daphylloside (5), phytol (6), and ursolic acid (7) were isolated from the leaves of Wendlandia formosana. Structure elucidation of the new iridoid glucosides was based on interpretation of high-resolution 1D and 2D NMR spectral data and chemical conversions. Antioxidant activity of Compounds (1-5) against diphenylpicrylhydrazyl (DPPH) and hydroxyl radical, and peroxynitrite was reported.

Topics: Antioxidants; Biphenyl Compounds; Humans; Iridoids; Phytotherapy; Picrates; Plant Extracts; Rubiaceae

Six new iridoid glucosides, 6'-O-trans-feruloylnegundoside (1), 6'-O-trans-caffeoylnegundoside (2), 2'-O-p-hydroxybenzoyl-6'-O-trans-caffeoylgardoside (3), 2'-O-p-hydroxybenzoyl-6'-O-trans-caffeoyl-8-epiloganic acid (4), 2'-O-p-hydroxybenzoyl gardoside (5), and 2'-O-p-hydroxybenzoyl-8-epiloganic acid (6), along with two known iridoids, agnuside and negundoside, have been isolated from the ethyl acetate extractive of the leaves of Vitex altissima. The structures of these compounds were elucidated on the basis of spectral data interpretation. These isolates did not exhibit significant 5-lipoxygenase enzyme inhibitory activity, but compounds 2-4 showed potent antioxidant activity by both the superoxide (NBT riboflavin photoreduction) free-radical-scavenging and DPPH-radical-scavenging methods. Compounds 1, 2, and negundoside were evaluated in a rat paw edema assay.

Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Biphenyl Compounds; Edema; Enzyme Inhibitors; Free Radical Scavengers; Glucosides; India; Iridoids; Lipoxygenase Inhibitors; Molecular Structure; Picrates; Plant Leaves; Plants, Medicinal; Rats; Rats, Wistar; Vitex

Activity-guided fractionation of the EtOAc and MeOH extract of the leaves of Syringa dilatata NAKAI furnished one free radical scavenger, the secoiridoid glucoside oleuropein together with ligstroside and an iridoid glucoside, syringopicroside. Oleuropein interacted with the stable free radical, 1,1-diphenyl-2-picrylhydrazyl (DPPH), and showed an IC(50) value of 40.4 microM. L-Ascorbic acid as a positive control showed an IC(50) value of 50.3 microM.

Topics: Biphenyl Compounds; Chromatography, High Pressure Liquid; Free Radical Scavengers; Humans; Inhibitory Concentration 50; Iridoids; Phytotherapy; Picrates; Plant Extracts; Plant Leaves; Syringa

Typical components of the Mediterranean diet, such as olive oil and red wine, contain high concentrations of complex phenols, which have been suggested to have an important antioxidant role. The aim of the present work was to determine the inhibitory potency of compounds such as oleuropein, hydroxytyrosol, and other structurally related compounds, such as gallic acid, toward reactive oxygen species generation and free radical scavenging ability. The potency of these compounds was also examined with respect to protecting in vitro low-density lipoprotein oxidation. These studies indicate that complex phenols, such as hydroxytyrosol, and gallic acid both inhibit free radical generation and act as free radical scavengers. The use of three different approaches to determine antioxidant potency demonstrates that activity in one test does not necessarily correlate with activity in another. It was also demonstrated that the presence of two phenolic groups is not always associated with antioxidant activity.

Topics: Animals; Antioxidants; Aryl Hydrocarbon Hydroxylases; Bepridil; Biphenyl Compounds; Cytochrome P-450 CYP3A; Cytochrome P-450 Enzyme Inhibitors; Enzyme Inhibitors; Free Radical Scavengers; Gallic Acid; Humans; Iridoid Glucosides; Iridoids; Lipid Peroxidation; Lipoproteins, LDL; Male; Microsomes, Liver; Olive Oil; Oxidoreductases, N-Demethylating; Phenylethyl Alcohol; Picrates; Plant Oils; Pyrans; Rats; Rats, Wistar; Reactive Oxygen Species; Steroid 16-alpha-Hydroxylase; Steroid Hydroxylases

From the ethanolic extract of the aerial parts of Globularia davisiana, a new iridoid glycoside, davisioside (1), was isolated. Davisioside (1) comprises a rare iridoid aglycone structure with a saturated double bond between C-3 and C-4. Nine known iridoid glycosides, asperuloside (2), alpinoside (3), geniposide (4), globularin (5), globularicisin (6), 10-O-benzoylcatalpol (7), lytanthosalin (8), melampyroside (9), agnuside (10), and three known phenylethanoid glycosides, verbascoside, isoacteoside and leucosceptoside A were also isolated and characterized. The structures of the isolates were established by spectroscopic methods (one-dimensional (1D)- and two-dimensional (2D)-NMR, MS).

Topics: Biphenyl Compounds; Chromatography, High Pressure Liquid; Iridoids; Magnetic Resonance Spectroscopy; Optical Rotation; Picrates; Scrophulariaceae; Spectrometry, Mass, Electrospray Ionization; Spectrometry, Mass, Fast Atom Bombardment; Spectrophotometry, Infrared