Effect ofBetula pendulaLeaf Extract onα-Glucosidase and Glutathione Level in Glucose-Induced Oxidative Stress

Abstract

B. pendulaleaf is a common ingredient in traditional herbal combinations for treatment of diabetes in southeastern Europe. Present study investigatedB. pendulaethanolic and aqueous extract as inhibitors of carbohydrate hydrolyzing enzymes, as well as their ability to restore glutathione concentration in Hep G2 cells subjected to glucose-induced oxidative stress. Phytochemical analysis revealed presence of rutin and other quercetin derivatives, as well as chlorogenic acid. In general, ethanolic extract was richer in phenolic substances than the aqueous extract. Furthermore, a comprehensive analysis of antioxidant activity of two extracts (determined by DPPH and ABTS radical scavenging activity, total antioxidant activity, and chelating activity as well as ferric-reducing antioxidant power) has shown that ethanolic extract was better radical scavenger and metal ion reductant. In addition, ethanolic extract effectively increased cellular glutathione levels caused by hyperglycemia and inhibitedα-glucosidase with the activity comparable to that of acarbose. Therefore,in vitroresearch usingB. pendulaplant extracts has confirmed their antidiabetic properties.