Kinetics of Tyrosinase Catalyzing Reaction Activated by 3-O-Caffeoylquinic Acid

Abstract

The effect of 3-O-caffeoylquinic acid on the monophenolase and diphenolase activity was tested. The experimental results showed that the activation effected of 3-O-caffeoylquinic acid on both monophenolase and diphenolase activity .3-O-caffeoylquinic acid concentration leading 50% activity increase (AC 50 ) was 10.50mg/L for monophenolase and 1.10g/L for diphenolase. 3-O-caffeoylquinic acid can remove the lag time of monophenolase. The activation kinetics of 3-O-caffeoylquinic acid analyzed by Lineweaver-Burk plots demonstrated a competitive activation for the oxidation of L-DOPA and the activation constants (K A ) was determined to be 1.12g/L.