摘要 : The action of Melothria extract on melanogenesis was studied. Melothria extract reduced melanin production to about 50% at final concentration of 5.0 #mu# g/mL, at which no change in cell viability was seen, in cultured B16 murine... 展开 The action of Melothria extract on melanogenesis was studied. Melothria extract reduced melanin production to about 50% at final concentration of 5.0 #mu# g/mL, at which no change in cell viability was seen, in cultured B16 murine melanoma cells. However, Melothria extract did not reduce tyrosinase activity of cultrued human melanocytes at all. Then, the action of Melothria extract in vivo was studied. We found that Melothria extract prevented hyperpigmentation induced by ultraviolet radiation in human and DBA/2 mouse skin. These results suggest that the depigmenting mechanism of Melothria extract in vivo involves suppression of some pigmentary signals in stimulating melanogenesis, rather than inhibition of tyrosinase activity. 收起