Antioxidative Activity of Tea Leaf Catechins

Abstract

Instant green tea was extracted with chloroform and ethyl acetate to obtain a crude catechin mixture. The four main tea catechin components (–)-epicatechin (EC), (–)-epigallocatechin (EGC), (–)-epicatechin gallate (ECg) and (–)-epigallocatechin gallate (EGCg) were isolated from the crude catechin by HPLC and purified. The antioxidative effects of the four catechins were tested by the active oxygen method (AOM) at 97.8°C on lard. The antioxidative activity increased in molarity in the following order: EC