Inhibitory effects of Cissus barbeyana leaf extracts on α-amylase and α-glucosidase in vitro

α-amylase and glucosidase inhibitors are used in the therapeutic management of type II diabetes mellitus. Inhibition of pancreatic α-amylase and membrane bound intestinal glucosidase by enzyme inhibitors results in delayed glucose absorption and reduces post prandial blood glucose rise in diabetic patients (1). Plants serve as a rich source of medicinally active compounds, including α-amylase and glucosidase inhibitors (2). The present study was carried out to investigate the in vitroα-amylase and glucosidase inhibitory effects of Cissus barbeyana. Hot water extract (CBWE) and ethanol extract (CBEE) of C. barbeyana leaves were prepared and used. Preliminary phytochemical screening of the extracts was also done. Phyto-constituents of the extracts were carbohydrates, tannins, resins, flavonoids and phenolics. Results show both extracts significantly (P<0.05) inhibited α-amylase, especially CBEE. The extracts also showed significant inhibition (30–33.51%) of α-glucosidase compared with acarbose, a known α-glucosidase inhibitor. These observations show the inhibition of α-amylase and glucosidase by C. barbeyana as a measure of potential antidiabetic activity. This activity will be further evaluated in vivo, which is currently under investigation.

References: 1. Kim, Y.M., Jeong, Y.K., Wang, M.H., Lee, W.Y., Rhee, H.I. (2005). Inhibitory effect of pine extract on alpha-glucosidase activity and postprandial hyperglycemia. Nutrition. 21: 756–761.

2. Mai, T.T., Thu, N.N., Tien, P.G., Van Chuyen, N. (2007). Alpha-glucosidase inhibitory and antioxidant activities of Vietnamese edible plants and their relationships with polyphenol contents. J. Nutr. Sci. Vitaminol. 53: 267–276.