Terpenoids from fruits of Amomum villosum and their hypoglycemic activity

Abstract

Eight terpenoids were isolated from the fruits of Amomum villosum by silica gel, Sephadex LH-20, Rp-C_(18), MCI GEL CHP20 P column chromatography, preparative TLC, and HPLC. Their structures were identified by HR-ESI-MS, ~1H and ~(13)C-NMR, IR, UV, [α]_D, and ECD spectroscopic data as kravanhin A 3-O-β-D-glucopyranoside(1), kravanhin B(2), 6-eudesmene-1β,4β-diol(3), oplodiol(4), vicodiol(5),(1R,2S,4R,7S)-vicodiol 9-O-β-D-glucopyranoside(6),(1R,2S,4S,5R)-angelicoidenol 2-O-β-D-glucopyranoside(7), and(1S,2S,4R,6S)-bornane-2,6-diol 2-O-β-D-glucopyranoside(8). Compound 1 was a new compound, and compounds 2-5 were isolated from A. villosum for the first time. Their hypoglycemic activity was tested based on STC-1 cell model and two enzymatic models(GPa and PTP1 B). The results showed that compounds 1, 7, and 8 could stimulate GLP-1 with the secretion rates of 692.8%, 398.6%, and 483.3% at 25.0 μmol·L~(-1), and compound 6 showed inhibitory activity against GPa with an IC_(50) value of 78.6 μmol·L~(-1).