Reactions of tea polyphenol four constituents with hydroxyl radical: A pulse radiolytic study

摘要

Using the electron pulse radiolytic techniques, the reactions between hydroxyl radical and tea polyphenol four constituents epigallocatechin gallate (EGCG), epicatechin gallate (ECG), epigallocatechin (EGC) and epicatechin (EC) have been investigated in detail, their corresponding rate constants for scavenging hydroxyl radicals have been determined to be 1.5×10 10 , 1.4×10 10 , 9.7×10 9 and 9.2×10 9 dm+3·mol -1 ·s -1 , respectively. On the basis of their structures and transient absorption spectra, the OH adducts of EGCG and ECG undergo unimolecular elimination of gallate group.