Inhibitoiy effects of Dendropanax morbifera leaf extracts on melanogenesis through down-regulation of tyrosinase and TRP-2

Abstract

Dendropanax morbifera (D. morbifera) grows in the southern coastal areas and on Jeju Island in Korea. In this study, D. morbifera leaf extract was investigated to determine the mechanism of its whitening effect. The inhibitory activities of the extract on melanogenesis were tested in B16 melanoma cells treated with the α-melanocyte stimulating hormone (α-MSH). D. morbifera leaf extracts remarkably decreased the melanin content at 25 and 50 µg/mL. The extracts significantly inhibited the intracellular tyrosinase activity and protein expression of tyrosinase and tyrosinase related protein-2 (TRP-2). In conclusion, D. morbifera leaf extracts would show a whitening effect by inhibiting intracellular tyrosinase activities and the expression of enzymes directly involved in the melanin biosynthesis. The results indicate that fractions of D. morbifera leaf extracts show potential for application as a whitening agent in the new whitening cosmetics.