[Pharmacological studies on leaf of Arctostaphylos uva-ursi (L.) Spreng. IV. Effect of 50% methanolic extract from Arctostaphylos uva-ursi (L.) Spreng. (bearberry leaf) on melanin synthesis].

Effects of 50% methanolic extract (U-ext) from the leaf of Arctostaphylos uva-ursi (L.) Spreng. (bearberry leaf) on melanin synthesis were investigated in vitro. The U-ext and arbutin isolated from the bearberry leaf had an inhibitory effect on tyrosinase activity. Furthermore, the U-ext inhibited the production of melanin from dopa by tyrosinase and from dopachrome by autoxidation. These results suggest that the bearberry leaf was found to be an effective inhibitor of the production of melanin.