Chemical Constituents of Hypoglycemic Activity in Vitro from Urtica fissa

Objective:To study the hypoglycemic activity in vitro and chemical constituents of Urtica fissa. Methods:In vitro hypoglycemic activities of roots,stems and leaves of Urtica fissa and the different polar solvent extraction phase of roots were compared by activity tracing method through inhibition of α-glucosidase. The compounds were isolated and purified by silica gel chromatography and recrystallization. The structures of compounds were identified according to physicochemical properties and spectral data,and the hypoglycemic of compounds were evaluated. Results:The ethyl acetate phase of ethanol extract in the roots of Urtica fissa showed the most significant in vitro hypoglycemic activity with the IC₅₀ value of 8.499mg/mL. Six compounds were isolated and identified as β-sitosterol,methyl p-hydroxycinnamate,n-hexadecanoic acid,p-methoxybenzaldehyde,trans-p-hydroxylcinnamic acid and carotenoid. Trans-p-hydroxylcinnamic acid and carotenoid exhibited significant inhibitory activities againstα-glucosidase with the IC₅₀ values of 5.234 and 1.693 mg/mL. Conclusion:The chemical constituents in the ethyl acetate phase of the ethanol extract from the root of Urticaria lobata had obvious hypoglycemic activity in vitro.