Potent α-glucosidase inhibitors from the roots of Panax japonicus C. A. Meyer var. major

Bioassay-guided fractionation of the CHCl3 soluble portion of the roots of Panax japonicus C. A. Meyer var. major afforded an active fraction with inhibitory activity against baker's yeast alpha-glucosidase with an IC50 value 1.02 mg/mL. Furthermore, the active fraction isolated contained three previously unreported polyacetylenes, designated panaxjapynes A-C, together with 11 other compounds, including four polyacetylenes, five phenolic compounds, a sesquiterpenoid, and a sterol glucoside. The structures of the compounds were elucidated by spectroscopic and chemical methods. Compared with the control acarbose (IC50 677.97 mu M), six compounds were shown to be more potent alpha-glucosidase inhibitors with IC50 values in the range 22.21-217.68 mu M. Crown Copyright (C) 2010 Published by Elsevier Ltd. All rights reserved.