Antioxidant activity of the isoflavonoids from the roots of Maackia amurensis

摘要

Seven isoflavonoids, including a new glycoside, (6aR,11aR)-medicarpin-3-O- gentiobioside (6), were isolated from the roots of Maackia amurensis using repeated column chromatography on a Toyopearl HW-50F sorbent and identified by HPLC-PDA-MS, ~1H NMR, ~(13)C, ~1H-~1H COSY, HSQC NMR and HMBC NMR analyses as daidzin (1), genistein-7-O-gentiobioside (2), pseudobaptigenin-7-O-gentiobioside (3), formononetin-7-O-gentiobioside (4), (6aR,11aR)-maackiain-3-O-gentiobioside (5), and 5-O-methylgenistein-7-O- gentiobioside (7). In the model of oxidative stress induced by formalin injection, the isolated isoflavone and pterocarpan glucosides 1-7 were shown to reduce the formation of malondialdehyde (MDA) and other thiobarbituric acid reactive substances (TBARS), as well as glutathione peroxidase (GPO) activity in rats.