抄録
Two new β-xylosyl derivatives of ginsenoside Re, 20(S)-protopanaxatriol 6-O-α-L-rhamnopyranosyl-(1→2)-[β-D-xylopyranosyl-(1→4)]-β-D-glucopyranosyl-20-O-β-D-glucopyranoside and 20(S)-protopanaxatriol 6-O-α-L-rhamnopyranosyl-(1→2)-[β-D-xylopyranosyl-(1→6)]-β-D-glucopyranosyl-20-O-β-D-glucopyranoside, were respectively synthesized from p-nitrophenyl β-D-xylopyranoside and phenyl β-D-xylopyranoside as donors and ginsenoside Re as the acceptor in 25% acetone and acetonitrile by a cellulase preparation from Trichoderma viride and a β-galactosidase preparation from Aspergillus oryzae. The latter enzyme preparation also catalyzed the hydrolysis of ginsenoside Re to the minor saponin, ginsenoside Rg2.