A Novel α-glycosidase Inhibitor

In this experiment, we used ethanol-aqueous solution as the extraction solvent. And we got the ethanolic extracts from mulberry branch barker (MBBEE), which was an inhibitor ofα-glycosidase activity. Then we explored the MBBEE's biological activity in vitro and in vivo. In this study, we also survey the relationship between the content of total flavonoids and theα-glucosidase inhibition activity of MBBEE from different varieties of mulberry branches. The results showed that the content of total flavonoids and its inhibition activity ofα-glucosidase of the MBBEE had no obvious relevance. In vitro the MBBEE had a good scavenging activity of DPPH radical with around 522~1030μg/mL of IC50 values. In vitro assay revealed that the strongly inhibited bothα-glucosidase and sucrase activities whose IC50 values were 1.91~3.5μg/mL and 0.6875~1.406μg/mL. The kinetic analysis showed that the MBBEE asα-glucosidase inhibitor characterized a competitive inhibition activity. Furthermore, the carbohydrate tolerance of normal mice was obviously enhanced (P<0.01, P<0.05, P<0.05) after the EMBB intragastric administration as compared to negative control. At 30, 60, 90 and 120 min post the intragastric administration with starch, the postprandial hyperglycemic of the type 2 diabetic mice can be very significantly decreased by supplying various concentration of the MBBEE (10~30 mg/kg body weight). Therefore, the MBBEE could effectively inhibit the postprandial hyperglycemia as a novelα-glucosidase activity inhibitor for the diabetic therapy.