Decursin and Z-ligustilide in angelica tenuissima root extract fermented by aspergillus oryzae display anti-pigment activity in melanoma cells

The anti-melanogenic effects of the extract of Angelica tenuissima (AT) root and the extract of AT root fermented by Aspergillus oryzae (FAT) were investigated. These effects were determined by measuring the inhibitory activity of AT and FAT on melanin production in B16F10 melanocytes and with in vitro tyrosinase activity assays. The AT extract inhibited melanin production at concentrations above 250 μg/ml, and this inhibitory effect was significantly enhanced by the fermentation process with A. oryzae. HPLC analysis resulted in the isolation of two active compounds from both the AT and FAT extracts. Their chemical structures were identified as decursin and Z-ligustilide through comparison with previously reported NMR data. The decursin and Z-ligustilide contents were increased in the FAT extract and could be responsible for its enhanced inhibitory effects on melanin production and tyrosinase activity compared with that of the AT extract.