Hydrolysis of epigallocatechin gallate using a tannase from Paecilomyces variotii

Epigallocatechin (EGC) and gallic acid (GA) were prepared by the degalloylation of an epigallocatechin gallate (EGCG) extract from green tea. EGCG was entirely hydrolyzed using a tannase (from Paecilomyces variotii) at pH 6.0, incubating at 40 degrees C for 30 min. The antiradical properties and the reducing power of these samples were assessed using the DPPH and FRAP assays, respectively. This work established a relationship between the antioxidant effects of epigallocatechin gallate and the enzymatic reaction products (epigalocatechin and gallic acid). The enzymatic reaction products showed higher scavenging activity and antioxidant capacity when compared to epigallocatechin gallate. (C) 2007 Elsevier Ltd. All rights reserved.