2-2--azino-di-(3-ethylbenzothiazoline)-6-sulfonic-acid and Hemolysis

2-2--azino-di-(3-ethylbenzothiazoline)-6-sulfonic-acid has been researched along with Hemolysis* in 16 studies

Other Studies

16 other study(ies) available for 2-2--azino-di-(3-ethylbenzothiazoline)-6-sulfonic-acid and Hemolysis

ArticleYear
Bioprospection of novel synthetic monocurcuminoids: Antioxidant, antimicrobial, and in vitro cytotoxic activities.
    Biomedicine & pharmacotherapy = Biomedecine & pharmacotherapie, 2021, Volume: 133

    The irrational use of medications has increased the incidence of microbial infections, which are a major threat to public health. Moreover, conventional therapeutic strategies are starting to become ineffective to treat these infections. Hence, there is a need to develop and characterize novel antimicrobial compounds. Phytochemicals are emerging as a safe and accessible alternative to conventional therapeutics for treating infectious diseases. Curcumin is extracted from the dried rhizome of the spice turmeric (Curcuma longa (Zingiberaceae)). However, the bioavailability of curcumin is low owing to its lipophilic property and thus has a low therapeutic efficacy in the host. A previous study synthesized structural variants of curcumin, which are called monocurcuminoids (CNs). CNs are synthesized based on the chemical structure of curcumin with only one methyl bridge. The biological activities of four previously synthesized CNs (CN59, CN63, CN67, and CN77), curcumin, and turmeric powder were examined in this study. Gas chromatography-tandem mass spectrometry analysis of curcumin and turmeric powder revealed similar peaks, which indicated the presence of curcumin in turmeric powder. The antioxidant activity of the test compounds was evaluated using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) assays. The ABTS radical scavenging activities of the test compounds were similar to those of vitamin C. The minimum inhibitory concentration (MIC) values of the test compounds against seven microbial strains were in the range of 4.06-150 μg/mL. The MIC value was equal to minimum bactericidal concentration value for CN63 (150 μg/mL) and CN67 (120 μg/mL) against Staphylococcus aureus. The treatment combination of CN77 (8.75 or 4.37 μg/mL) and turmeric powder (9.37 or 4.68 μg/mL) exerted synergistic growth-inhibiting effects on Aeromonas hydrophila, Candida albicans, and Pseudomonas aeruginosa. Photodynamic therapy using 2X MIC of CN59 decreased the growth of Enterococcus faecalis by 4.18-fold compared to the control group and completely inhibited the growth of Escherichia coli. The results of the hemolytic assay revealed that the test compounds were not cytotoxic with half-maximal inhibitory concentration values ranging from 49.65-130.9 μM. The anticoagulant activity of most compounds was comparable to that of warfarin but higher than that of heparin. This indicated that these compounds target t

    Topics: Animals; Anti-Infective Agents; Antioxidants; Bacteria; Benzothiazoles; Bioprospecting; Biphenyl Compounds; Blood Coagulation; Candida albicans; Diarylheptanoids; Drug Resistance, Microbial; Hemolysis; Microbial Sensitivity Tests; Photochemotherapy; Photosensitizing Agents; Picrates; Sheep, Domestic; Sulfonic Acids

2021
Bergenin from Peltophorum dubium: Isolation, Characterization, and Antioxidant Activities in Non-Biological Systems and Erythrocytes.
    Medicinal chemistry (Shariqah (United Arab Emirates)), 2017, Volume: 13, Issue:6

    Bergenin, a compound derived from gallic acid, is a secondary metabolite of the plant Peltophorum dubium (Spreng.) Taub.. In this study, we aimed to characterize the ability of bergenin to eliminate the radicals in non-biological systems.. We evaluated bergenin's ability to protect erythrocytes from oxidative damage in a biological system. We have elucidated bergenin structure using nuclear magnetic resonance, X-ray diffraction, Fourier transform infrared spectroscopy, and differential scanning calorimetry. We then evaluated its antioxidant capacity in vitro against DPPH•, ABTS•+, hydroxyl radicals, and nitric oxide, and determined its ability to transfer electrons owing to its reduction potential and ability to chelate iron. We also evaluated its protective capacity against oxidative damage produced by AAPH in erythrocytes, its hemolytic properties, its ability to inhibit hemolysis, and its ability to maintain intracellular reduced glutathione homeostasis.. Bergenin concentrations between 0.1 and 3mM significantly (p < 0.05) and dose dependently decreased formation of ABTS•+, DPPH•, nitrite ions, OH•, reduced formation ferricyanide, ferrozine-Fe2+complex, inhibited AAPH-induced oxidative hemolysis of erythrocytes, raised GSH levels in the presence of AAPH, inhibited AAPH-induced lipid peroxidation in erythrocytes.. Bergenin may represent a novel alternative antioxidant, with potential applications in various industries, including drugs, cosmetics, and foods.

    Topics: Animals; Antioxidants; Benzopyrans; Benzothiazoles; Biphenyl Compounds; Electron Transport; Erythrocytes; Fabaceae; Female; Glutathione; Hemolysis; Homeostasis; Hydroxyl Radical; Intracellular Space; Iron; Lipid Peroxidation; Models, Molecular; Molecular Conformation; Nitrites; Picrates; Rats; Rats, Wistar; Sulfonic Acids

2017
Antioxidant activity and acetylcholinesterase inhibition of grape skin anthocyanin (GSA).
    Molecules (Basel, Switzerland), 2014, Jul-03, Volume: 19, Issue:7

    We aimed to investigate the antioxidant and acetylcholinesterase inhibitory activities of the anthocyanin rich extract of grape skin. Grape skin anthocyanin (GSA) neutralized free radicals in different test systems, such as 2,-2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) assays, to form complexes with Fe2+ preventing 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH)-induced erythrocyte hemolysis and oxidative DNA damage. Moreover, GSA decreased reactive oxygen species (ROS) generation in isolated mitochondria thus inhibiting 2',-7'-dichlorofluorescin (DCFH) oxidation. In an in vivo study, female BALB/c mice were administered GSA, at 12.5, 25, and 50 mg per kg per day orally for 30 consecutive days. Herein, we demonstrate that GSA administration significantly elevated the level of antioxidant enzymes in mice sera, livers, and brains. Furthermore, GSA inhibited acetylcholinesterase (AChE) in the in vitro assay with an IC50 value of 363.61 µg/mL. Therefore, GSA could be an excellent source of antioxidants and its inhibition of cholinesterase is of interest with regard to neurodegenerative disorders such as Alzheimer's disease.

    Topics: Acetylcholinesterase; Animals; Benzothiazoles; Biphenyl Compounds; Cholinesterase Inhibitors; DNA Damage; Drug Evaluation, Preclinical; Erythrocytes; Female; Free Radical Scavengers; Fruit; Hemolysis; Inhibitory Concentration 50; Mice, Inbred BALB C; Mitochondria, Liver; Oxidation-Reduction; Oxidative Stress; Picrates; Plant Extracts; Sulfonic Acids; Vitis

2014
Evaluation of antioxidant activities of ampelopsin and its protective effect in lipopolysaccharide-induced oxidative stress piglets.
    PloS one, 2014, Volume: 9, Issue:9

    The aim of this study was to investigate the antioxidant potential of ampelopsin (APS) by using various methods in vitro, as well as to determine effects of APS on LPS-induced oxidative stress in piglets. The results showed that APS exhibited excellent free radical scavenging by DPPH, ABTS, O2•-, H2O2 and ferric reducing antioxidant power. Ampelopsin also protected pig erythrocytes against AAPH-induced apoptosis and hemolysis, decreased total superoxide dismutase activity, and increased lipid peroxidation. Furthermore the results demonstrated that APS enhanced the total antioxidant capacity and decreased the malondialdehyde and protein carbonyl contents in LPS-treated piglets. The results of the present investigation suggest that APS possesses a strong antioxidant activity and alleviates LPS-induced oxidative stress, possibly due to its ability to prevent reactive oxygen species.

    Topics: Amidines; Animals; Antioxidants; Apoptosis; Benzothiazoles; Biphenyl Compounds; Erythrocytes; Female; Flavonoids; Hemolysis; Hydrogen Peroxide; Inflammation; Injections, Intraperitoneal; Lipid Peroxidation; Lipopolysaccharides; Malondialdehyde; Oxidants; Oxidative Stress; Picrates; Protein Carbonylation; Sulfonic Acids; Superoxide Dismutase; Superoxides; Swine

2014
In vitro effects of arylhydrocoumarin on free radicals and oxidative stress in erythrocytes and Saccharomyces cerevisiae.
    Current pharmaceutical biotechnology, 2014, Volume: 15, Issue:11

    Neoflavonoids comprise a group of natural compounds with varied chemical structures and promising pharmacological properties, including antioxidant capacity. This work describes an evaluation of the in vitro antioxidant capacity of a new coumarin derivative, i.e., 7-acetoxy-4-aryl-3,4-dihydrocoumarin, in terms of its ability to quench the 2,2- diphenyl-1-picrylhydrazyl (DPPH•), 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS•+), hydroxyl (OH•) and superoxide anion (O2(•-)) radicals, as well as its capacity to initiate electron transfer by reducing potential and inhibit lipid peroxidation by TBARS (thiobarbituric acid reactive substances) method. In addition, the antioxidant capacity of 7-acetoxy-4-aryl-3,4-dihydrocoumarin was evaluated against oxidative damage induced by hydrogen peroxide in erythrocyte suspensions and S. cerevisiae strains. In all methodologies investigated, high antioxidant capacities above 65% were demonstrated by 7-acetoxy-4-aryl-3,4-dihydrocoumarin against the DPPH(•), ABTS(•+), OH(•) and O2(•-) radicals. The ability of 7-acetoxy-4-aryl-3,4-dihydrocoumarin to inhibit oxidative damage induced by hydrogen peroxide in erythrocytes and S. cerevisiae strains demonstrates the importance of this compound in the protection against oxidative stress at the cellular level. Thus, the results obtained in this study suggest that 7-acetoxy-4-aryl-3,4-dihydrocoumarin can assist the development of new antioxidant products for possible use in the prevention or reduction of diseases related to oxidative stress.

    Topics: Animals; Antioxidants; Benzothiazoles; Biphenyl Compounds; Coumarins; Dose-Response Relationship, Drug; Erythrocytes; Free Radicals; Hemolysis; Lipid Peroxidation; Oxidative Stress; Picrates; Rats; Saccharomyces cerevisiae; Sulfonic Acids

2014
Antioxidant capacity and radical scavenging effect of polyphenol rich Mallotus philippenensis fruit extract on human erythrocytes: an in vitro study.
    TheScientificWorldJournal, 2014, Volume: 2014

    Mallotus philippinensis is an important source of molecules with strong antioxidant activity widely used medicinal plant. Previous studies have highlighted their anticestodal, antibacterial, wound healing activities, and so forth. So, present investigation was designed to evaluate the total antioxidant activity and radical scavenging effect of 50% ethanol fruit glandular hair extract (MPE) and its role on Human Erythrocytes. MPE was tested for phytochemical test followed by its HPLC analysis. Standard antioxidant assays like DPPH, ABTS, hydroxyl, superoxide radical, nitric oxide, and lipid peroxidation assay were determined along with total phenolic and flavonoids content. Results showed that MPE contains the presence of various phytochemicals, with high total phenolic and flavonoid content. HPLC analysis showed the presence of rottlerin, a polyphenolic compound in a very rich quantity. MPE exhibits significant strong scavenging activity on DPPH and ABTS assay. Reducing power showed dose dependent increase in concentration absorption compared to standard, Quercetin. Superoxide, hydroxyl radical, lipid peroxidation, nitric oxide assay showed a comparable scavenging activity compared to its standard. Our finding further provides evidence that Mallotus fruit extract is a potential natural source of antioxidants which have a protective role on human Erythrocytes exhibiting minimum hemolytic activity and this justified its uses in folklore medicines.

    Topics: Acetophenones; Antioxidants; Benzopyrans; Benzothiazoles; Biphenyl Compounds; Chromatography, High Pressure Liquid; Chromatography, Thin Layer; Erythrocytes; Free Radical Scavengers; Fruit; Hemolysis; Humans; Hydroxyl Radical; Lipid Peroxidation; Mallotus Plant; Nitric Oxide; Oxidation-Reduction; Phytochemicals; Picrates; Plant Extracts; Polyphenols; Reference Standards; Sulfonic Acids

2014
Characterization and biological studies on Co(II), Ni(II) and Cu(II) complexes of carbohydrazones ending by pyridyl ring.
    Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy, 2013, Volume: 104

    The chelating behavior of ligands based on carbohydrazone core modified with pyridine end towards Co(II), Ni(II) and Cu(II) ions have been examined. The ligands derived from the condensation of carbohydrazide with 2-acetylpyridine (H(2)APC) and 4-acetylpyridine (H(2)APEC). The (1)H NMR, IR data and the binding energy calculations of H(2)APC revealed the presence of two stereoisomers syn and anti in the solid state and in the solution. The (1)H NMR, IR data and the binding energy calculations confirmed the presence of H(2)APEC in one keto form only in the solid state and in the solution. The spectroscopic data confirmed that H(2)APC behaves as a monobasic pentadentate in Co(II) and Cu(II) complexes and as mononegative tetradentate in Ni(II) complex. On the other hand, H(2)APEC acts as a mononegative tridentate in Co(II) complex, neutral tridentate in Ni(II) complex and neutral bidentate in Cu(II) complex. The electronic spectra and the magnetic measurements of complexes as well as the ESR of the copper complexes suggested the octahedral geometry. The bond length and bond angles were evaluated by DFT method using material studio program. The thermal behavior and the kinetic parameters of degradation were determined using Coats-Redfern and Horowitz-Metzger methods. The antioxidant (DDPH and ABTS methods), anti-hemolytic and in vitro Ehrlich ascites of the compounds have been screened.

    Topics: Animals; Antineoplastic Agents; Antioxidants; Benzothiazoles; Biphenyl Compounds; Carcinoma, Ehrlich Tumor; Cobalt; Copper; Electron Spin Resonance Spectroscopy; Electrons; Erythrocytes; Free Radical Scavengers; Hemolysis; Hydrazones; Inhibitory Concentration 50; Kinetics; Ligands; Magnetic Resonance Spectroscopy; Mice; Models, Molecular; Nickel; Picrates; Pyridines; Rats; Spectrophotometry, Infrared; Sulfonic Acids; Thermogravimetry

2013
Evaluation of antioxidant activity of vanillin by using multiple antioxidant assays.
    Biochimica et biophysica acta, 2011, Volume: 1810, Issue:2

    Vanillin, a compound widely used in foods, beverages, cosmetics and drugs, has been reported to exhibit multifunctional effects such as antimutagenic, antiangiogenetic, anti-colitis, anti-sickling, and antianalgesic effects. However, results of studies on the antioxidant activity of vanillin are not consistent.. We systematically evaluated the antioxidant activity of vanillin using multiple assay systems. DPPH radical-, galvinoxyl radical-, and ABTS(+)-scavenging assays, ORAC assay and an oxidative hemolysis inhibition assay (OxHLIA) were used for determining the antioxidant activity.. Vanillin showed stronger activity than did ascorbic acid and Trolox in the ABTS(+)-scavenging assay but showed no activity in the DPPH radical- and galvinoxyl radical-scavenging assays. Vanillin showed much stronger antioxidant activity than did ascorbic acid and Trolox in the ORAC assay and OxHLIA. In the ABTS(+)-scavenging assay, ORAC assay and OxHLIA, vanillin reacted with radicals via a self-dimerization mechanism. The dimerization contributed to the high reaction stoichiometry against ABTS(+) and AAPH-derived radicals to result in the strong effect of vanillin. Oral administration of vanillin to mice increased the vanillin concentration and the antioxidant activity in plasma. These data suggested that antioxidant activity of vanillin might be more beneficial than has been thought for daily health care.. Based on the results of the present study, we propose the addition of antioxidant capacity to the multifunctionality of vanillin.

    Topics: Animals; Antioxidants; Ascorbic Acid; Benzaldehydes; Benzhydryl Compounds; Benzothiazoles; Biphenyl Compounds; Chromans; Chromatography, High Pressure Liquid; Dose-Response Relationship, Drug; Drug Evaluation, Preclinical; Erythrocytes; Free Radical Scavengers; Hemolysis; Mice; Molecular Structure; Oxidation-Reduction; Picrates; Sheep; Sulfonic Acids

2011
Cytotoxic and protective DNA damage of three new diterpenoids from the brown alga Dictoyota dichotoma.
    European journal of medicinal chemistry, 2011, Volume: 46, Issue:1

    Three new diterpenes Amijiol acetate (3), dolabellane, Dolabellatrienol (4), and dolastane, Amijiol-7, 10-diacetate (9) were isolated together with the previously described Pachydictyol A (1), Isopachydictyol A (2), 8β-hydroxypachydictyol A (5), Amijiol (6), Isodictyohemiacetal (7) and Dictyol C (8) from the Red Sea brown alga Dictyota dichotoma var. implexa. The structures and relative stereochemistry of the new diterpenoids were proposed on the basis of their spectral data. Compounds 3 and 9 have potent activity against DNA damage, cytotoxicity against WI-38, HepG2, and MCF-7 cell lines, and antioxidant using ABTS and erythrocytes hemolysis.

    Topics: Animals; Antineoplastic Agents; Antioxidants; Benzothiazoles; Cell Line, Tumor; Cell Survival; Chlorocebus aethiops; Diterpenes; DNA Damage; Erythrocytes; Hemolysis; Humans; Phaeophyceae; Sulfonic Acids; Vero Cells

2011
The antioxidant properties of carnitine in vitro.
    Cellular & molecular biology letters, 2010, Volume: 15, Issue:1

    Many of the effects of carnitine are ascribed to its antioxidant properties. The aim of this study was to evaluate the antioxidant properties of carnitine in vitro. Carnitine was found to decolorize ABTS(*+), and to protect fluorescein against bleaching induced by AAPH-derived peroxyl radicals and peroxynitrite, thiol groups against oxidation induced by hydrogen peroxide, peroxyl radicals, hypochlorite and peroxynitrite, and erythrocytes against hemolysis induced by peroxyl radicals and hypochlorite. These results show that carnitine has a direct antioxidant action against physiologically relevant oxidants.

    Topics: Antioxidants; Benzothiazoles; Carnitine; Erythrocytes; Hemolysis; Hypochlorous Acid; Peroxides; Peroxynitrous Acid; Sulfonic Acids

2010
Reassessment of antioxidant activity of arbutin: multifaceted evaluation using five antioxidant assay systems.
    Free radical research, 2010, Volume: 44, Issue:4

    Arbutin, a practically used skin-lightening agent, has been reported to possess a weak antioxidant activity compared to that of its precursor, hydroquinone. However, its antioxidant activity has not been systematically evaluated. Hence, this study reassessed its activity using five assay systems. Assays were first performed using model radicals, DPPH radical and ABTS(*+). Arbutin showed weak DPPH radical-scavenging activity compared to that of hydroquinone, but showed strong ABTS(*+)-scavenging activity. Its activity by ORAC assay was then evaluated using a physiologically relevant peroxyl radical. Arbutin exerted weak but long-lasting radical-scavenging activity and showed totally the same antioxidant activity as that of hydroquinone. Finally, it was shown that, in two cell-based antioxidant assays using erythrocytes and skin fibroblasts, arbutin exerted strong antioxidant activity comparable or even superior to that of hydroquinone. These findings indicate that the antioxidant activity of arbutin may have been under-estimated and suggest that it acts as a potent antioxidant in the skin.

    Topics: Animals; Antioxidants; Arbutin; Benzothiazoles; Biphenyl Compounds; Cell Survival; Cells, Cultured; Dose-Response Relationship, Drug; Erythrocytes; Fibroblasts; Hemolysis; Humans; Hydroquinones; Oxidative Stress; Picrates; Sheep; Structure-Activity Relationship; Sulfonic Acids; Thiazoles; Time Factors

2010
Phenolic and enolic hydroxyl groups in curcumin: which plays the major role in scavenging radicals?
    Journal of agricultural and food chemistry, 2009, Nov-25, Volume: 57, Issue:22

    The aim of this work is to clarify the antioxidant abilities of phenolic and enolic hydroxyl groups in curcumin. 1,7-bis(4-benzyloxy-3-methoxyphenyl)-1,6-heptadiene-3,5-dione (BEC), 1,7-bis(4-hydroxy-3-methoxyphenyl)heptane-3,5-diol (OHC), 1,7-bis(4-hydroxy-3-methoxyphenyl)heptane-3,5-dione (THC), and 1,7-bis(3,4-dihydroxyphenyl)-1,6-heptadiene-3,5-dione (BDC) are synthesized to determine the antioxidant activities by using antiradical assays against 2,2'-diphenyl-1-picrylhydrazyl (DPPH) radical, galvinoxyl radical, and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonate) cation radical (ABTS*+) and by protecting DNA and erythrocyte against 2,2'-azobis(2-amidinopropane hydrochloride) (AAPH) induced oxidation. The phenolic hydroxyl is the main group for curcumin to trap DPPH, galvinoxyl, and ABTS*+ radicals. The conjugative system between enolic and phenolic hydroxyl groups is beneficial for curcumin to protect erythrocytes against hemin-induced hemolysis and to protect DNA against AAPH-induced oxidation, but is not beneficial for curcumin to protect erythrocytes against AAPH-induced hemolysis. More hydroxyl groups enhance the antioxidant effectiveness of curcumin in the experimental systems employed herein. Therefore, curcumin acts as an antioxidant through the phenolic hydroxyl group.

    Topics: Antioxidants; Benzhydryl Compounds; Benzothiazoles; Biphenyl Compounds; Curcumin; DNA; Free Radical Scavengers; Hemolysis; Humans; Oxidation-Reduction; Phenols; Picrates; Sulfonic Acids

2009
Antioxidant properties of 2-O-beta-D-glucopyranosyl-L-ascorbic acid.
    Bioscience, biotechnology, and biochemistry, 2008, Volume: 72, Issue:6

    The antioxidant activity of a provitamin C agent, 2-O-beta-D-glucopyranosyl-L-ascorbic acid (AA-2betaG), was compared to that of 2-O-alpha-D-glucopyranosyl-L-ascorbic acid (AA-2G) and ascorbic acid (AA) using four in vitro methods, 1,1-diphenyl-picrylhydrazyl (DPPH) radical-scavenging assay, 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radical cation (ABTS(*+))-scavenging assay, oxygen radical absorbance capacity (ORAC) assay, and 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH)-induced erythrocyte hemolysis inhibition assay. AA-2betaG slowly and continuously scavenged DPPH radicals and ABTS(*+) in roughly the same reaction profiles as AA-2G, whereas AA quenched these radicals immediately. In the ORAC assay and the hemolysis inhibition assay, AA-2betaG showed similar overall activities to AA-2G and to AA, although the reactivity of AA-2betaG against the peroxyl radical generated in both assays was lower than that of AA-2G and AA. These data indicate that AA-2betaG had roughly the same radical-scavenging properties as AA-2G, and a comprehensive in vitro antioxidant activity of AA-2betaG appeared to be comparable not only to that of AA-2G but also to that of AA.

    Topics: Amidines; Animals; Antioxidants; Ascorbic Acid; Benzothiazoles; Erythrocytes; Hemolysis; Hydrogen-Ion Concentration; Molecular Structure; Sheep; Sulfonic Acids

2008
Antioxidative effect of melatonin on DNA and erythrocytes against free-radical-induced oxidation.
    Chemistry and physics of lipids, 2008, Volume: 151, Issue:2

    The aim of this work is to investigate the antioxidative effect of melatonin (N-acetyl-5-methoxytryptamine) on the oxidation of DNA and human erythrocytes induced by 2,2'-azobis(2-amidinopropane hydrochloride) (AAPH). First, the 50% inhibition concentration (IC50) of melatonin is measured by reacting with two radical species, i.e., 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonate) radical cation (ABTS*+) and 2,2'-diphenyl-1-picrylhydrazyl (DPPH). The IC50 of melatonin are 75microM and 300microM when melatonin reacts with ABTS*+ and DPPH, respectively. Especially, the reactions of melatonin with ABTS*+ and DPPH are the direct evidence for melatonin to trap radicals. Then, melatonin is applied to protect DNA and human erythrocytes against oxidative damage and hemolysis induced by 2,2'-azobis(2-amidinopropane hydrochloride) (AAPH). The presence of melatonin prolongs the occurrence of the oxidative damage of DNA and hemolysis of erythrocytes, generating an inhibition period (t(inh)). The proportional relationship between t(inh) and the concentration of melatonin ([MLT]) is treated by the chemical kinetic equation, t(inh)=(n/R(i))[MLT], in which n means the number of peroxyl radical trapped by an antioxidant, and R(i) stands for the initiation rate of the radical reaction. It is found that every molecule of melatonin can trap almost two radicals in protecting DNA and erythrocytes. Furthermore, quantum calculation proves that the indole-type radical derived from melatonin is much stable than amide-type radical. Finally, melatonin is able to accelerate hemolysis of erythrocytes induced by hemin, indicating that melatonin leads to the collapse of the erythrocyte membrane in the presence of hemin. This may provide detailed information for the usage of melatonin and helpful reference for the design of indole-related drugs.

    Topics: Antioxidants; Benzothiazoles; Biphenyl Compounds; DNA; Erythrocytes; Free Radicals; Hemin; Hemolysis; Humans; Hydrazines; Melatonin; Models, Molecular; Molecular Structure; Oxidation-Reduction; Picrates; Sulfonic Acids

2008
Antioxidant properties of Aller-7, a novel polyherbal formulation for allergic rhinitis.
    Drugs under experimental and clinical research, 2004, Volume: 30, Issue:3

    Allergic rhinitis, a frequently occurring immunological disorder affecting men, women and children worldwide, is a state of hypersensitivity that occurs when the body overreacts to a substance such as pollen, mold, mites or dust. Allergic rhinitis exerts inflammatory response and irritation of the nasal mucosal membranes leading to sneezing; stuffy/runny nose; nasal congestion; and itchy, watery and swollen eyes. A novel, safe polyherbal formulation (Aller-7/NR-A2) has been developed for the treatment of allergic rhinitis using a unique combination of extracts from seven medicinal plants including Phyllanthus emblica, Terminalia chebula, Terminalia bellerica, Albizia lebbeck, Piper nigrum, Zingiber officinale and Piper longum. In this study, the antioxidant efficacy of Aller-7 was investigated by various assays including hydroxyl radical scavenging assay, superoxide anion scavenging assay, 1,1-diphenyl-2-picryl hydrazyl (DPPH) and 2,2-azinobis-ethyl-benzothiozoline-sulphonic acid diammonium salt (ABTS) radical scavenging assays. The protective effect of Aller-7 on free radical-induced lysis of red blood cells and inhibition of nitric oxide release by Aller-7 in lipopolysaccharide-stimulated murine macrophages were determined. Aller-7 exhibited concentration-dependent scavenging activities toward biochemically generated hydroxyl radicals (IC50 741.73 microg/ml); superoxide anion (IC50 24.65 microg/ml by phenazine methosulfate-nicotinamide adenine dinucleotide [PMS-NADH] assay and IC50 4.27 microg/ml by riboflavin/nitroblue tetrazolium [NBT] light assay), nitric oxide (IC50 16.34 microg/ml); 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical (IC50 5.62 microg/ml); and 2,2-azinobis-ethyl-benzothiozoline-sulphonic acid diammonium salt (ABTS) radical (IC50 7.35 microg/ml). Aller-7 inhibited free radical-induced hemolysis in the concentration range of 20-80 microg/ml. Aller-7 also significantly inhibited nitric oxide release from lipopolysaccharide-stimulated murine macrophages. These results demonstrate that Aller-7 is a potent scavenger of free radicals and that it may serve.

    Topics: Animals; Antioxidants; Benzothiazoles; Biphenyl Compounds; Butylated Hydroxyanisole; Catechin; Dose-Response Relationship, Drug; Drug Evaluation, Preclinical; Erythrocytes; Gallic Acid; Hemolysis; Humans; Hydrazines; Hydroxyl Radical; Inhibitory Concentration 50; Lipopolysaccharides; Macrophages; Medicine, Traditional; Mice; Nitric Oxide; Nitroblue Tetrazolium; Phytotherapy; Picrates; Plant Extracts; Plants, Medicinal; Rhinitis, Allergic, Perennial; Rhinitis, Allergic, Seasonal; Riboflavin; Sulfonic Acids; Superoxides

2004
Evaluation of the enzymatic assay of serum uric acid with 2,2'-azino-di(3-ethylbenzthiazoline-6-sulphonate) (ABTS) as chromogen.
    Annals of clinical biochemistry, 1984, Volume: 21 ( Pt 6)

    A spectrophotometric method for the determination of serum uric acid based on the oxidation of 2,2'-azino-di(3-ethylbenzthiazoline-6-sulphonate) by use of uricase and peroxidase has already been reported. The method is very precise (CV less than 4.7%). The standard curve is linear up to 4640 mumol/L. Comparison with other enzymatic methods gave good correlation. The method gave results 9% lower than the phosphotungstate method. The effects of bilirubin, haemoglobin, glucose, ascorbic acid, anticoagulants and purine compounds were studied. The reference values for this method are 140.8-407.8 mumol/L for female subjects and 145.6-514.7 mumol/L for male subjects.

    Topics: Anticoagulants; Ascorbic Acid; Benzothiazoles; Bilirubin; Blood Glucose; Hemolysis; Humans; Indicators and Reagents; Purines; Reference Values; Sulfonic Acids; Uric Acid

1984