iridoids and swerchirin

The crude extract of Swertia chirayita, an important medicinal plant of Nepal, is locally used for many diseases including type 2 diabetes. In this study, crude aqueous and 12% ethanol solution extracts of S. chirayita collected from nine districts of Nepal were analyzed for anti-diabetic-linked anti-hyperglycemia potential using in vitro biochemical assays. There was moderate-to-high positive correlation between antioxidant activity and total phenolic content of both extracts and moderate-to-high α-glucosidase inhibitory activity. Although the anti-diabetic property of S. chirayita is mainly attributed to the phytochemical swerchirin present in its hexane fraction, we propose that the crude extract of this plant used in local healing also has anti-hyperglycemia potential. The crude extracts indicated the presence of three main phytochemicals mainly mangiferin, swertiamarin, and amarogentin and their derivatives. Among the standard compounds (mangiferin, swertiamarin, and amarogentin), mangiferin showed α-glucosidase and 2,2-diphenyl-1-picrylhydrazyl radical inhibitory activity indicating anti-hyperglycemia potential.

Topics: Angiotensin-Converting Enzyme Inhibitors; Antioxidants; Biphenyl Compounds; Chromatography, High Pressure Liquid; Glycoside Hydrolase Inhibitors; Hypoglycemic Agents; Inhibitory Concentration 50; Iridoids; Nepal; Phenols; Picrates; Plant Extracts; Swertia; Xanthones

Concentrations of seven phytochemical constituents (swertiamarin, mangiferin, swertisin, oleanolic acid, 1,5,8-trihydroxy-3-methoxyxanthone, 1,8-dihydroxy-3,7-dimethoxyxanthone and 1,8-dihydroxy-3,5-dimethoxyxanthone) of "ZangYinChen" (Swertia mussotii, a herb used in Tibetan folk medicine) were determined and compared in plants collected from naturally distributed high-altitude populations and counterparts that had been artificially cultivated at low altitudes. Levels of mangiferin, the most abundant active compound in this herb, were significantly lower in cultivated samples and showed a negative correlation with altitude. The other constituents were neither positively nor negatively correlated with cultivation at low altitude. Concentrations of all of the constituents varied substantially with growth stage and were highest at the bud stage in the cultivars, but there were no distinct differences between flowering and fruiting stages in this respect.

Topics: Agriculture; Altitude; Drug Evaluation, Preclinical; Flowers; Geography; Glucosides; Iridoid Glucosides; Iridoids; Medicine, Tibetan Traditional; Oleanolic Acid; Plant Physiological Phenomena; Plants, Medicinal; Pyrones; Seeds; Swertia; Time Factors; Xanthones

Topics: Flavonoids; Glucosides; Iridoid Glucosides; Iridoids; Japan; Luteolin; Plant Extracts; Plants, Medicinal; Pyrones; Xanthenes; Xanthones