Abstract
The hydrolysis of protopanaxadiol-type saponin mixture by various glycoside hydrolases was examined. Among these enzymes, crude preparations of lactase from Aspergillus oryzae, β-galactosidase from A. oryzae, and cellulase from Trichoderma viride were found to produce ginsenoside F2 [3-O-(β-D-glucopyranosyl)-20-O-β-D-glucopyranosyl-20(S)-protopanaxadiol], compound K [20-O-β-D-glucopyranosyl-20(S)-protopanaxadiol], and ginsenoside Rd {3-O-[β-D-glucopyranosyl-(1→2)-β-D-glucopyranosyl]-20-O-β-D-glucopyranosyl-20(S)-protopanaxadiol}, respectively, from protopanaxadiol-type saponin mixture in large quantities. Moreover, the crude preparation of lactase from Penicillium sp. having a high producing activity of ginsenoside Rh1 (6-O-β-D-glucopyranosyl-20(S)-protopanaxatriol) from protopanaxatriol-type saponin mixture gave ginsenoside Rd as a main product, ginsenoside Rg3 {3-O-[β-D-glucopyranosyl-(1→2)-β-D-glucopyranosyl]-20(S)-protopanaxadiol}, and compound K from protopanaxadiol-type saponin mixture. The hydrolytic pathways of ginsenosides Rb1, Rb2, and Rc to ginsenosides Rd, Rg3, and F2, and compound K by crude preparations of four glycoside hydrolases were also studied. This is the first report on the enzymatic preparation of an intestinal bacterial metabolite, ginsenoside F2, in quantity, and a considerable amount of a minor saponin, ginsenoside Rg3, from a protopanaxadiol-type saponin mixture.
