Abstract: Aim To screen for α-glucosidase inhibitor from Glycyrrhiza uralensis Fisch.. Methods Glycyrrhizic acid, glycyrrhetinic acid, flavonoids of glycyrrhiza, alkaloids of glycyrrhiza, and glycyrrhiza polysaccharides were isolated from the root of Glycyrrhiza uralensis Fisch. respectively. Three compounds were isolated from the flavonoids of glycyrrhiza as guided by the α-glucosidase inhibitory test in vitro. Moreover, the characteristics of inhibitory kinetics of glycyrol and glycyrrhetinic acid were investigated. Results The flavonoids of glycyrrhiza and glycyrrhetinic acid had the strongest α-glucosidase inhibitory activity. Glycyrol, β-sitosterol and liquiritin were isolated and identified. Glycyrol was a fast-binding, reversible, noncompetitive α-glucosidase inhibitor, showing IC50 at 0.26 μg·mL^-1. Glycyrrhetinic acid was a fast-binding, irreversible α-glucosidase inhibitor, showing IC50 at 102.4 μg·mL^-1. Conclusion Glycyrol is an effective α-glucosidase inhibitor.

Key words: α-glucosidase inhibitor, α-glucosidase inhibitor, Glycyrrhiza uralensis Fisch., Glycyrrhiza uralensis Fisch., glycyrol, glycyrol, glycyrrhetinic acid, glycyrrhetinic acid