Microbial deglycosylation and ketonization of ginsenosides Rg1 and Rb1 by Fusarium oxysporum

Two major ginsenosides, ginsenoside-Rg(1) (1) and ginsenoside-Rb-1 (2), were transformed by the fungus Fusarium oxysporum f. sp. Lycopersici (Z-001). 1 was converted into five metabolites, ginsenoside-F-1 (3), 6a, 12 beta-dihydroxydammar-3-one-20(S)-O-beta-D-glucopyranoside (4), 3a-oxa-3a-homo-6 alpha, 12 beta-dihydroxydammar-3-one-20(S)-O-beta-D-glucopyranoside (5), 20(S)-protopanaxatriol (6), and 3-oxo-20(S)-protopanaxatriol (7). 2 was converted into four metabolites, ginsenoside-Rd (8), ginsenoside-F-2 (9), compound K (10), and 12 beta-hydroxydammar-3-one-20(S)-O-beta-D-glucopyranoside (11). The structures of these metabolites were determined by the analysis of extensive spectroscopic data. Among them, 4 and 5 were two new compounds. Deglycosylation and ketonization at C-3 were recognized as the characteristic reactions of this strain.