Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7585317 | Food Chemistry | 2018 | 7 Pages |
Abstract
There are eight most abundant green tea catechins (GTCs) existing in four pairs of eipimers, and carbon-3 configuration represents the only steric difference within each pair. This study aimed to use a new kinetic approach to elucidate the effect of stereochemical changes on the antioxidant activity. A mixture of eight GTCs was treated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) prepared in a series of concentrations, their relative reaction rates towards scavenging DPPH were revealed by the recently introduced parameter, i.e. Dm. The 3-R configuration in (â)-epicatechin, (â)-epigallocatechin and (â)-epigallocatechin gallate gave lower Dm values demonstrating faster kinetics as opposed to their 3-S counterparts, with the only exception of the pair of (â)-catechin gallate and (â)-epicatechin gallate in which 3-S configuration was faster. These results suggested that the kinetic approach adopted in this study could reflect the different antioxidant activity of GTCs attributed by minor steric changes.
Related Topics
Physical Sciences and Engineering
Chemistry
Analytical Chemistry
Authors
Hong Yang, Xuejia Xue, Huan Li, Siti Norasikin Apandi, Su Chin Tay-Chan, Seng Poon Ong, Edmund Feng Tian,