Isolation of the saponins from Momordica charantia and their PTP1B inhibition activity
SHI Xue-ping1, YAO Hui-yuan2, ZHANG Wei-ming1
(1 Nanjing Institute for Comprensive Utilization of Wild Plant, Nanjing, 210042, Jiangsu, China; 2 College of Food Science and Technology, Southern Yangtze University, Wuxi 214036, Jiangsu, China)
Abstract:
Five compounds were isolated from Momordica charantia L through the absorption of macroporous resin, silica gel column chromatography, reversed-phase silica gel column chromatography and detection of thin-layer chromatography (TLC). The structures of the compounds were characterized through the spectral technology including ESI-MS and NMR. They are α-spinasterol-3-O-β-D-glucopyranoside (A), 19(R)-carbonyl-25-dimethoxy-5β-5,19-epoxycucrbita-6,23-dien-3β-ol-3-O-β-D-glucopyranoside (B), momordicoside A (C), momordicoside L (D), and momordicoside K (E), respectively. The hypoglycemic activities of these five compounds were tested by using PTP1B (protein tyrosine phosphatase). The results indicated that the compounds D and E have not inhibition effect on PIP1B but the compound A, B and C have the inhibition effect. The sequence of inhibition activities is A＞C＞B.
KeyWords:
Momordica charantia L.; saponins; inhibition; protein tyrosine phosphatase (PTP1B); isolation
