Radical-induced oxidation of trans-resveratrol.

Abstract

trans-Resveratrol (RVT) (3,5,4'-trihydroxystilbene), a polyphenolic constituent of red wine, is thought to be beneficial in reducing the incidence of cardiovascular diseases, partly via its antioxidant properties. However, the mechanism of action by which trans-resveratrol displays its antioxidant effect has not been totally unravelled. This study aimed at establishing a comprehensive scheme of the reaction mechanisms of the direct scavenging of HO(*) and O(2)(*-) radicals generated by water gamma radiolysis. Aerated aqueous solutions of trans-RVT (from 10 to 100μmolL(-1)) were irradiated with increasing radiation doses (from 25 to 400Gy) and further analyzed by UV-visible absorption spectrophotometry for detection of trans-RVT oxidation products. Separation and quantification of RVT and its four oxidation products previously identified by mass spectrometry, i.e., piceatannol (PCT), 3,5-dihydroxybenzoic acid (3,5-DHBA), 3,5-dihydroxybenzaldehyde (3,5-DHB) and para-hydroxybenzaldehyde (PHB), were performed by HPLC/UV-visible spectrophotometry. Determination of the radiolytic yields of trans-RVT consumption and oxidation product formation has allowed us to establish balance between trans-RVT disappearance and the sum of oxidation products formation. Under our conditions, O(2)(-) radicals seemed to poorly initiate oxidation of trans-RVT, whereas the latter, whatever its initial concentration, quantitatively reacted with HO() radicals, via a dismutation mechanism. Two reaction pathways involving HO()-induced trans-RVT primary radicals have been proposed to explain the formation of the oxidation end-products of trans-RVT.

• Authors: Laurent Camont, Fabrice Collin, Martine Couturier, Patrice Thérond, Daniel Jore, Monique Gardès-Albert, Dominique Bonnefont-Rousselot
• Journal: Biochimie (Biochimie) Vol. 94 Issue 3 Pg. 741-7 (Mar 2012) ISSN: 1638-6183 [Electronic] France
• PMID: 22120111 (Publication Type: Journal Article)
• Copyright: Copyright © 2011 Elsevier Masson SAS. All rights reserved.

Chemical References

• Reactive Oxygen Species
• Stilbenes
• Hydroxyl Radical
• Resveratrol

Topics

• Gamma Rays
• Hydroxyl Radical (chemistry)
• Oxidation-Reduction
• Reactive Oxygen Species (chemistry)
• Resveratrol
• Stilbenes (chemistry)