ISOLATION AND IDENTIFICATION OF ACETYL-COA CARBOXYLASE INHIBITORS FROM GREEN TEA (CAMELLIA-SINENSIS)

An aqueous methanol extract from green tea showed potent acetyl-CoA ca rboxylase inhibitory activity. An active compound was isolated from th e extract and identified as (-)-epigallocatechin gallate by instrument al analyses, The IC50 value of (-)-epigallocatechin gallate was 3.1 x 10(-4) M. Among tea catechins and related compounds, nearly equal acti vity was found in(-)-epigallocatechin gallate and (-)epicatechin galla te, whereas (+)-catechin, (-)-epicatechin, (-)-epigallocatechin, galli c acid and methyl gallate each had no inhibitory activity. These resul ts indicate that the 3-O-gallate group of the catechin structure was n ecessary for this activity. (-)-Epigallocatechin gallate inhibited tri glyceride accumulation in 3T3-L1 cells at a concentration of 1.0 x 10( -7) M or higher.