Enzymatic Synthesis of (+)Catechin-α-glucoside and Its Effect on Tyrosinase Activity

Abstract

The glycosidation of (+)catechin, which has five hydroxyl groups with cyclodextrin glucanotransferase (CGTase, EC 2.4.1.19) and soluble starch has been studied. One of the transfer products was purified and its structure was determined to be (+)catechin 3ʹ-0-α-D-glucopyranoside. This glucoside noncompetitively inhibited the activity of tyrosinase from mushroom, IC₅₀ being 5.8 mM, but didn’t inhibit that from mouse melanoma. In contrast, arbutin (hydroquinone-0-β-D-glucopyranoside) inhibited both tyrosinases.