Abstract: Objective To investigate the inhibitory effects of traditional Chinese medicine (TCM) on hypermelanosis and provide experimental evidence for treating skin pigmentary disorders. Methods Five TCMs with strong inhibitory effects on tyrosinase activity were tested. The changes of the number and morphology of melanocytes induced by UVB were observed in the experimental hypermelanosis model (brownish guinea pig). Results Decreased melanocytes and melanin granules were found with the treatment of Poria cocos, Polyporus umbellatus, Cornus officinalis Sieb. et Zucc., Atractylodes macrocephala Koidz., Astoagalus complanatus R. Br. ex Bge. Conclusion There are inhibitory effects on hypermelanosis induced by UVB with the treatment of Poria cocs, Polyporus umbellatus, Cornus officinalis Sieb.et Zucc., Atractylodes macrocephala Koidz., Astoagalus complanatus R. Br.ex Bge.

Key words: Atractylodes macrocephala, Astrogalus complanatus, Cornus officinalis, Polyporus umbellatus, Poria cocos, Skin pigmentation, Monophenol monooxygenase