Inhibitory activies of different theafl avins against tyrosinase

To study the inhibitory activies of fi ve theafl avins(theafl avin, TF1; theafl avins-3-gallate, TF2A; theaflavins-3′-gallate, TF2B; theaflavins-3,3′-gallate, TF3; theaflavic acid, TF4) against tyrosinase, comparing with that of epigallocatechin gallate(EGCG) as the positive control. Tyrosinase activity was determined by the o-hydroxylation of L-tyrosine. As the results, the five kinds of theaflavins inhibited the activities of tyrosinase with different extent, and showed dose-effect relationship. Except TF4, the tyrosinase inhibition of other four theaflavins(TF1, TF2A, TF2B and TF3) was significant superior to epigallocatechin gallate.