Initial study on alpha-glucosidase inhibitory effect of polypore fungi sample and blepharis maderapatensis

Abstract

Alpha-glucosidase enzymes play important role in hyrolysis polysaccharides and oligosaccharides to glucose in human body after meal. Thus, controlling blood glucose level by alpha-glucosidase enzyme inhibitors is considered as a therapy for carbonhydrate mediated diseases. Triterpenes extracted from natural sources have been reported to have a wide range of biological activities. The aims of this study were to evaluate alpha-glucosidase inhibitory effects of triterpenes isolated from Ganoderma species and Blepharis maderaspatensis collected from Vietnam. Crude triterpene yield of Ganoderma applanatum was found to be as 6.695% whereas those of Ganoderma capense, Ganoderma submubraculum, and B. maderaspatensis were 0.44%, 0.6%, 4.97%, respectively. In vitro alpha-glucosidase inhibitory assay was conducted by using enzyme alpha-glucosidase (Sigma) with the test concentration range of 20-10000 μg/ml and Acarbose (Bayer Pharmaceuticals) was used as the positive control. Triterpenses from all three species and the herbal plant possessed alpha-glucosidase inhibitory effects and had lower IC50 values compared to the positive control (Acarbose, Bayer Pharmaceuticals). The lowest IC50 values was of Ganoderma applanatum 105.1967179 (μg/ml), while G. capense, G. submubraculum and B. maderaspatensis were 138.1597126, 134.5170837, 13513.51351 (μg/ml) repectively. Whereas, that of the positive control was 125000 (μg/ml). From the above results, it would be concluded that these fungal specimens, especially G. applanatum might be a potential source of alternative compounds for diabetes treatment. Keywords: alpha-glucosidase inhibitors, triterpenes, Ganoderma species, Blepharis maderaspatensis.