Undescribed Triterpenes from the Leaves of Syzygium myrsinifolium with Their α-Glucosidase and α-Amylase Inhibition Activity.

Two undescribed triterpenes, syzyfolium A (1) and syzyfolium B (2), together with twelve known compounds, terminolic acid (3), actinidic acid (4), piscidinol A (5), threo-dihydroxydehydrodiconiferyl alcohol (6), lariciresinol-4-O-ß-D-glucoside (7), icariol A2 (8), 14ß,15ß-dihydroxyklaineanone (9), garcimangosone D (10), (+)-catechin (11), myricetin-3-O-α-L-rhamnopyranoside (12), quercitrin (13), and 3, 4, 5-trimethoxyphenyl-(6'-O-galloyl)-O-ß-D-glucopyranoside (14) were isolated from the leaves of Syzygium myrsinifolium. Their chemical structures were determined by IR, HR-ESI-MS, 1D and 2D NMR spectra. Compounds 3 and 4 inhibited significantly α-glucosidase with IC50 values of 23.99 and 36.84, respectively, and compounds 1 and 2 inhibited significantly α-amylase with IC50 values of 35.48 and 43.65 µM, respectively.

Furostane Saponins from the Seeds of Allium ramosum and Their Lipid Accumulation Inhibitory Activity.

Three new furostane saponins, ramofurosides A-C (1-3), and two known saponins, fistulosaponin B (4) and (25R)-26-O-ß-D-glucopyranosyl-1ß,3ß,26-trihydroxyfurosta-5,20(22)-diene-1-O-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranoside (5) were isolated from the methanol extract of Allium ramosum seeds. Their structures were identified based on spectroscopic evidence and comparison with those reported in the literature. All compounds were evaluated for reduction of lipid accumulation in HepG2 cell lines. As a result, compounds 1 and 3 showed a significant reduction in total lipid content by 27.93±3.05 and 27.54±1.68 %, respectively, at a concentration of 100 µM.