Proanthocyanidins from the leaves of Machilus philippinensis
Journal
Journal of Natural Products
Journal Volume
73
Journal Issue
8
Pages
1375-1380
Date Issued
2010
Author(s)
Lin H.-C.
Abstract
Seven proanthocyanidins (2-8) together with epicatechin (1) were isolated from the EtOH extract of the leaves of Machilus philippinensis. Of these, machiphilitannins A (7) and B (8) are new natural products, with respective IC50 values of 31.3 (7) and 18.4 μM (8) against α-glucosidase type IV from Bacillus stearothermophilus. Their structures were elucidated mainly on the basis of CD and 2D NMR analyses. In addition, aesculitannin B (2) showed inhibitory activity against α-glucosidase with an IC50 value of 3.5 μM. This work demonstrates for the first time that the purified proanthocyanidins possess inhibitory activity against α-glucosidase type IV. © 2010 The American Chemical Society and American Society of Pharmacognosy.
Type
journal article