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

Resveratrol (3,5,4'-trihydroxystilbene) is a phytoalexin produced by plants. Resveratrol is known for its anti-cancer, antiviral and antioxidant properties. We prepared imine analogs of resveratrol ((hydroxyphenyliminomethyl)phenols) and tested their antioxidant activity. All prepared resveratrol analogs were able to scavenge 2,2-diphenyl-1-picrylhydrazyl (DPPH), galvinoxyl radical (GOR) and 2,2'-azino-bis(3-ethylbenzothiazoline)-6-sulphonic acid (ABTS) radicals. The antioxidant activity efficiency correlated with the number and position of hydroxyl groups. The most effective antioxidants were resveratrol analogs containing three hydroxyl groups in the benzylidene part of their molecules. These results provide new insights into the relationship between the chemical structure and biological activity of resveratrol analogs.

Topics: Benzhydryl Compounds; Benzothiazoles; Biphenyl Compounds; Free Radical Scavengers; Molecular Structure; Picrates; Resveratrol; Stilbenes; Sulfonic Acids

Evidence shows beneficial effects of resveratrol (RES) on human health. However, its poor aqueous solubility limits therapeutic effectiveness. Thus, the use of nanostructured delivery systems for RES, such as a liquid-crystalline system (LCS), could be viable. The purpose of this study was to develop, characterize, and determine the in vivo effectiveness of a RES-loaded LCS. We studied an LCS containing silicon glycol copolymer, polyether functional siloxane, and the polymeric dispersion carbomer homopolymer type B (C974) in the ratio 20:55:25 with and without RES. Results obtained using polarized light microscopy, small-angle X-ray scattering, and rheology analysis showed that the RES-loaded LCS system presents a lamellar structure and behaves as a non-Newtonian fluid presenting pseudoplastic (the apparent viscosity decreases as the stress increases) and thixotropic (the apparent viscosity decreases with the duration of stress) behaviors. Cytotoxicity studies showed that the formulation components are noncytotoxic. Topical application of a RES-loaded LCS protected hairless mice from UVB-irradiation-induced skin damage by inhibiting edema, neutrophil recruitment, lipid hydroperoxide and superoxide anion production, gp91phox mRNA expression, and oxidative stress. The RES-loaded LCS maintained 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and ferric reducing abilities, catalase activity, reduced glutathione levels, and mRNA expression of glutathione peroxidase 1 and glutathione reductase. The RES-loaded LCS also up-regulated matrix metalloproteinase-9 activity, IL-10 production, and mRNA expression of transcription factor Nrf2 and heme oxygenase-1. Therefore, a RES-loaded LCS is a promising new therapeutic approach to mitigate skin photodamage.

Topics: Animals; Antioxidants; Benzothiazoles; Edema; Female; Glutathione; Glutathione Peroxidase; Glutathione Peroxidase GPX1; Heme Oxygenase-1; Humans; Inflammation; Interleukin-10; Matrix Metalloproteinase 9; Mice; Mice, Hairless; Molecular Structure; Oxidative Stress; Resveratrol; Skin; Stilbenes; Sulfonic Acids; Superoxides; Ultraviolet Rays

Eight phenolic compounds including: p-coumaric acid, vanillic acid, caffeic acid, chlorogenic acid, trolox, quercetin, curcumin, and resveratrol were treated with riboflavin (RF) photosensitization and in vitro antioxidant capacities of the mixtures were determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2' azino bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), and ferric reducing antioxidant power (FRAP) assays. Mixtures containing p-coumaric acid and vanillic acid under RF photosensitization showed increases in ferric ion reducing ability and radical scavenging activity of DPPH, whereas mixtures of other compounds had decreases in both radical scavenging ability and ferric reducing antioxidant power. Hydroxycoumaric acid and conjugated hydroxycoumaric and coumaric acids were tentatively identified from RF photosensitized p-coumaric acid, whereas dimmers of vanillic acid were tentatively identified from RF photosensitized vanillic acid. RF photosensitization may be a useful method to enhance antioxidant properties like ferric ion reducing abilities of some selected phenolic compounds.

Topics: Antioxidants; Benzothiazoles; Biphenyl Compounds; Caffeic Acids; Chlorogenic Acid; Chromans; Coumaric Acids; Curcumin; Light; Molecular Structure; Oxidation-Reduction; Phenols; Picrates; Plant Extracts; Propionates; Quercetin; Resveratrol; Riboflavin; Stilbenes; Sulfonic Acids; Vanillic Acid

Stilbenoids are polyphenolic phytoalexins that exhibit potential health applications in humans. Hairy root cultures of muscadine grape (Vitis rotundifolia Michx.) were used to study the biochemical and molecular regulation of stilbenoid biosynthesis upon treatment with 100 μM methyl jasmonate (MeJA) or 10 mM hydrogen peroxide (H2O2) over a 96-h period. Resveratrol, piceid, and ε-viniferin were identified in higher concentrations in the tissue whereas resveratrol was the most abundant stilbenoid in the medium under either treatment. An earlier increase in resveratrol accumulation was observed for the MeJA-treated group showing a maximum at 12 h in the tissue and 18 h in the medium. Furthermore, the antioxidant capacity of extracts from the tissue and medium was determined by the 2,2'-azinobis[3-ethylbenzthiazoline sulfonic acid] (ABTS) and the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assays showing correlation with the stilbenoid content. Fourteen candidate reference genes for qPCR were tested under the described experimental conditions and resulted in the selection of 5 reference genes. Quantitative analyses of transcripts for phenylalanine ammonia-lyase (PAL), resveratrol synthase (RS), and two stilbene synthases (STS and STS2) showed the highest RNA level induction at 3 h for both treatments with a higher induction for the MeJA treatment. In contrast, the flavonoid-related chalcone synthase (CHS) transcripts showed induction and a decrease in expression for MeJA and H2O2 treatments, respectively. The observed responses could be related to an oxidative burst triggered by the exposure to abiotic stressor compounds with signaling function such as MeJA and H2O2 which have been previously related to the synthesis of secondary metabolites.

Topics: Acetates; Antioxidants; Benzothiazoles; Biphenyl Compounds; Culture Media; Cyclopentanes; Genes, Plant; Hydrogen Peroxide; Oxylipins; Picrates; Plant Roots; RNA, Plant; Stilbenes; Sulfonic Acids; Vitis

A new stilbene, 2',3,4',5,5'-pentahydroxy-cis-stilbene (1), along with 13 known compounds, resveratrol (2), oxyresveratrol (3), norartocarpetin (4), kuwanon C (5), morusin (6), cudraflavone A (7), kuwanon G (8), albafurane C (9), mulberrofuran G (10), 3-O-acetyl-α-amyrin (11), 3-O-acetyl-β-amyrin (12) ursolic acid-3-O-acetate (13) and uvaol (14), were isolated from the barks of Morus nigra. Compounds 2, 8, 10, 12 and 14 are reported for the first time from this plant. The isolated compounds were elucidated by means of 1D and 2D NMR, UV, IR and MS, as well as by comparison with the literature data. The isolated compounds and the different extracts were evaluated for their potential antioxidant activity using 2,2'-azino-bis-(3-ethylbenzthiazoline-6-sulfonic acid)(+) radical-scavenging capacity assay and compared with ascorbic acid. The new stilbene (1) exhibited remarkable antioxidant capacity with IC50 of 4.69 μM.

Topics: Antioxidants; Benzofurans; Benzothiazoles; Egypt; Flavonoids; Molecular Structure; Morus; Nuclear Magnetic Resonance, Biomolecular; Plant Bark; Plant Extracts; Resveratrol; Stilbenes; Sulfonic Acids; Terpenes

Smilax china root, which is rich in resveratrol and oxyresveratrol, has been used as emergency foods as well as folk medicine. This study investigated changes in concentration of bioactive components and the free-radical scavenging capacity of Smilax china root during fermentation by Aspergillus usami and Saccharomyces cerevisiae.. Resveratrol, oxyresveratrol and piceid were quantified as major constituents in Smilax china root by using UPLC-ESI-MS. The concentration of oxyresveratrol and resveratrol remarkably increased through fermentation and the transformation of piceid to resveratrol. Its concentration in 4% Smilax china root was 1.16-2.95 times higher than that of a 2% preparation throughout fermentation. The vitamin C equivalent antioxidant capacity of 2% Smilax china root was 1.51-1.91 times higher than that of 4% Smilax china root during fermentation. Meanwhile, ABTS free-radical scavenging capacity was enhanced up to 95.07 and 99.35% for 2% and 4% Smilax china root, respectively.. Results from our study propose that bioactive components in Smilax China root were highly extracted by fermentation followed by saccharification and ethanol production, resulting in enhanced free-radical scavenging capacity. © 2013 Society of Chemical Industry.

Topics: Aspergillus; Benzothiazoles; Fermentation; Free Radical Scavengers; Glucosides; Humans; Plant Extracts; Plant Roots; Resveratrol; Saccharomyces cerevisiae; Smilax; Stilbenes; Sulfonic Acids

Although polyphenols represent the paradigm of the health-promoting effects ascribed to grape products, recently, attention has been paid to dietary melatonin, significantly present in Mediterranean foods. In this work, we measured melatonin, its isomers, stilbenes (trans- and cis-resveratrol and their glucosides, piceids) and total polyphenols in some different grape products (red, white and dessert wines, grape juices and Modena balsamic vinegars) of distinct Italian areas. We also evaluated their antiradical activity by DPPH(·) and ABTS(·+) assays. For indoleamine analysis, the separation was carried out on a 1.7-μm C18 BEH column and the detection performed by means of mass spectrometry with electrospray ionization in positive ion mode with multiple reaction monitoring. The confirmation of the peak identity was accomplished by injection into the high-resolution system (Orbitrap) using accurate mass measurements (error below 1.0 ppm). Mass spectrometry analyses revealed, for the first time, the presence of melatonin in dessert wines and balsamic vinegars, as well as the occurrence of three different melatonin isomers in grape products.

Topics: Analysis of Variance; Antioxidants; Benzothiazoles; Beverages; Biphenyl Compounds; Chromatography, High Pressure Liquid; Isomerism; Linear Models; Melatonin; Picrates; Spectrometry, Mass, Electrospray Ionization; Stilbenes; Sulfonic Acids; Tandem Mass Spectrometry; Vitis; Wine

Mulberry fruits (Morus alba L.), rich in health beneficial compounds such as polyphenols, flavonoids, and anthocyananis, have traditionally been used as nutritional foodstuffs and fork medicines. In this study, physicochemical properties and antioxidant activities of a traditional Korean alcoholic beverage ``yakju'' enriched with mulberry were evaluated. The beverage was enriched with smoothies prepared from Korean mulberry cultivars of Cheongilppong (CP), Suwonppong (SP), and Daesungppong (DP). In comparison to the control, an increase in alcohol content and total acidity and a decrease in sugar level in yakju enriched with mulberry were observed during 15 d of fermentation. The total polyphenol and total flavonoid content increased in the following order: DP yakju > SP yakju > CP yakju > control yakju. In contrast, the anthocyanin content decreased during the fermentation periods. The trans-resveratrol content of mulberry yakju increased during the fermentation and the resveratrol content of DP yakju (0.24 mg/L) was significantly higher than that of SP yakju (0.21 mg/L) and CP yakju (0.14 mg/L) on the 15th day of fermentation (P < 0.05). The antioxidant activities of mulberry yakju, which was assessed using the 1,1-diphenyl-2-picryl hydrazyl (DPPH), 2,2'-azino-bis-(3-ethylbenozothiazoline-6-sulfonic acid) (ABTS), ferric reducing antioxidant power (FRAP), and reducing power assays, decreased during the 1st day of fermentation and increased into thereafter. The increase in antioxidant activities of mulberry yakju might have been affected primarily by the total flavonoid and total polyphenol content with increasing alcohol concentration, as a good extractor, during the fermentation; however, the antioxidant activities may have also been affected by the total anthocyanin content up to the 1st day of fermentation.. The physicochemical properties and antioxidant activities of a traditional Korean alcoholic beverage ``yakju'' enriched with mulberry were investigated. This analysis is important for the potential applications of mulberry yakju as functional alcoholic drinks.

Topics: Alcoholic Beverages; Anthocyanins; Antioxidants; Benzothiazoles; Biphenyl Compounds; Chemical Phenomena; Fermentation; Flavonoids; Food Handling; Fruit; Morus; Picrates; Polyphenols; Republic of Korea; Resveratrol; Stilbenes; Sulfonic Acids

The antioxidant activity of resveratrol in the absence and presence of increasing concentrations of HP-β-CDs was determined using three different methods: ORAC, ABTS and DPPH. The three methods were validated and compared for their linearity, precision and accuracy in measuring resveratrol antioxidant activity. The results indicated that the most sensitive method is the ORAC assay, which can measure the lowest resveratrol concentration (0.15-2 μM) with the highest precision. In the presence of increasing concentrations of HP-β-CDs, the antioxidant activity of resveratrol was seen to increase when it was measured by the ORAC and ABTS assays. However, no increase was observed when the DPPH assay was used. With the ORAC assay, the antioxidant activity increased until all the resveratrol had been included in HP-β-CDs (0.4 mM CDs), whereas in the case of ABTS assay the plateau in antioxidant activity was reached after 2 mM HP-β-CDs, suggesting that the CDs interferences in the measurement method. When the DPPH assay was used, no effect was observed when increasing concentrations of HP-β-CDs, indicating that in a methanolic medium resveratrol is free. Therefore, so this method cannot be used to measure the effect of resveratrol complexation with CDs on its antioxidant activity.

Topics: Antioxidants; Benzothiazoles; Biphenyl Compounds; Cyclodextrins; Limit of Detection; Oxidation-Reduction; Picrates; Reactive Oxygen Species; Reproducibility of Results; Resveratrol; Stilbenes; Sulfonic Acids; Thiazoles

New resveratrol analogues containing five- and six-membered nitroxides and isoindoline nitroxides were synthesized. These new compounds were compared to resveratrol based on their ABTS radical scavenging ability as well on their capacity to suppress inflammatory process in macrophages induced by lipopolysaccharides. The ABTS and ROS scavenging activities of new molecules were the same or weaker than that of resveratrol, but some of paramagnetic resveratrol derivatives suppressed nitrite and TNFα production more efficiently than resveratrol. Based on these results the new nitroxide and phenol containing hybrid molecules can be considered as new antioxidant and anti-inflammatory agents.

Topics: Animals; Anti-Inflammatory Agents; Benzothiazoles; Cell Line; Free Radical Scavengers; Lipopolysaccharides; Macrophages; Mice; Reactive Oxygen Species; Resveratrol; Stilbenes; Sulfonic Acids; Tumor Necrosis Factor-alpha

The antioxidant capacity of butylated hydroxytoluene (BHT; 2,6-di-tert-butyl-p-cresol), propyl gallate (3,4,5-trihydroxybenzoic acid n-propyl ester), resveratrol (trans-3,4',5-trihydroxystilbene), and vitamins C (l-ascorbic acid) and E [(+)-alpha-tocopherol] was studied in chemical and biological systems. The chemical assays evaluated the capacity of these antioxidants to sequester 2,2'-azinobis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS.) and 1,1 diphenyl-2-picrylhydrazyl (DPPH.). A new colorimetric method to determine hydroxyl radical scavenging is also described. The biological tests use the eucaryotic cells of Saccharomyces cerevisiae treated with the antioxidants in the presence of the stressing agents apomorphine, hydrogen peroxide, and paraquat dichloride (methylviologen; 1,1'-dimethyl-4,4'-bipyridinium dichloride). The results in chemical systems showed that all of the antioxidants were able to significantly inhibit the oxidation of beta-carotene by hydroxyl free radicals. The assays in yeast showed that the antioxidant activity of the tested compounds depended on the stressing agent used and the mechanism of action of the antioxidant.

Topics: Antioxidants; Apomorphine; Ascorbic Acid; Benzothiazoles; beta Carotene; Biphenyl Compounds; Butylated Hydroxytoluene; Hydrogen Peroxide; Hydroxyl Radical; Oxidation-Reduction; Paraquat; Picrates; Propyl Gallate; Resveratrol; Saccharomyces cerevisiae; Stilbenes; Sulfonic Acids; Vitamin E

A number of model compounds resembling the fundamental bonding patterns of residual kraft lignin, including a series of stilbenes, were incubated with laccase from Trametes versicolor in the presence and absence of delignification 'mediators' ABTS and HBT. The condensed kraft lignin model compounds seem to undergo initial degradation by laccase mainly via benzylic oxidation, demethylation and hydroxylation reactions. Phenolic 5-5', diphenylmethane and alpha-5 lignin models were found to be degraded mainly via side-chain oxidation reactions. Among the models studied, a phenolic stilbene was found to be the most reactive, yielding several products showing side-chain oxidation/transposition, demethoxylation and hydroxylation reactions. Non-phenolic 5-5', diphenylmethane and stilbene model compounds were found unreactive even in the presence of the laccase-mediator system.

Topics: Basidiomycota; Benzothiazoles; Biodegradation, Environmental; Indicators and Reagents; Laccase; Lignin; Models, Molecular; Molecular Structure; Oxidation-Reduction; Oxidoreductases; Stilbenes; Structure-Activity Relationship; Substrate Specificity; Sulfonic Acids