Methylation of tea catechins by rat liver homogenates

Biosci Biotechnol Biochem. 1999 Feb;63(2):430-2. doi: 10.1271/bbb.63.430.


Methylation of (-)-epigallocatechin (EGC), (-)-epicatechin gallate (ECg), and (-)-epigallocatechin gallate (EGCg) was carried out with a rat liver homogenate and S-adenosyl-L-methionine. A structural analysis of the reaction products by MS and NMR showed that 4'-O-methyl EGC, 4"-O-methyl ECg, and 4"-O-methyl EGCg had been formed from EGC, ECg, and EGCg, respectively. These results suggest that methylation may be one of the metabolic pathways to the catechins.

MeSH terms

  • Animals
  • Catechin / analogs & derivatives
  • Catechin / metabolism*
  • Chromatography, High Pressure Liquid
  • Flavonoids / metabolism
  • Liver / metabolism*
  • Magnetic Resonance Spectroscopy
  • Male
  • Methylation
  • Rats
  • Rats, Wistar
  • S-Adenosylmethionine / metabolism
  • Spectrometry, Mass, Fast Atom Bombardment
  • Tea / metabolism*


  • Flavonoids
  • Tea
  • S-Adenosylmethionine
  • Catechin
  • epicatechin gallate
  • epigallocatechin gallate
  • gallocatechol