Biotechnology Letters, Vol.35, No.1, 91-95, 2013
Microbial transformation of 20(S)-protopanaxatriol by Absidia corymbifera and their cytotoxic activities against two human prostate cancer cell lines
Seven hydroxylates of 20(S)-protopanaxatriol (1) transformed by Absidia corymbifera AS 3.3387 were isolated and identified by spectral methods including 2D-NMR. Among them, 7 beta-hydroxyl-20(S)-protopanaxatriol (2), 7 alpha-hydroxyl-20(S)-protopanaxatriol (3), and 7 beta, 15 alpha-dihydroxyl-20(S)-protopanaxatriol (7) are new compounds. The metabolites 2, 6, 7, and 8 showed the more potent inhibitory effects against DU-145 and PC-3 cell lines than the substrate.