Screening and identification of potent α-glycosidase inhibitors from Gardenia jasminoides Ellis

The α-glycosidase inhibition assay is used to examine the inhibition activity of traditional Chinese medicines through extraction with methanol. The α-glycosidase inhibition activity of the isolated compounds is measured by α-glycosidase inhibition assay and compared with Acarbose. Molecular docking is implemented to study the interaction between isolated compounds and CtMGAM (maltase–glucoamylase-C) or NtMGAM (maltase–glucoamylase-N). Compared with those of Acarbose, the methanol extract of Gardenia jasminoides Ellis has a higher activity to inhibit α-glycosidase among the 74 traditional Chinese medicines. Geniposide and Gardenoside, isolated compounds from Gardenia jasminoides Ellis, have better inhibition activity (IC50 values of 0.35 and 0.46 mg/ml, respectively) than Acarbose (IC50 values of 0.75 mg/ml). The molecular docking results show that Geniposide and Gardenoside have specific binding affinities with CtMGAM and can be considered comparable to those of Acarbose. Our findings illuminate the possible anti-diabetic mechanism of Gardenia jasminoides Ellis and support its use for the treatment of diabetes.