In vitro inhibitory effects of cranberry bean (Phaseolus vulgaris L.) extracts on aldose reductase, α-glucosidase and α-amylase

摘要

The in vitro inhibitory activities of different seed extracts prepared from cranberry bean mutant SA-05 and its wild-type variety Hwachia against aldose reductase, α-glucosidase and α-amylase were examined. The results indicated that the polyphenolics-rich extracts obtained using 800 g kg~(-1) methanol and 500 g kg~(-1) ethanol demonstrated inhibitory activities against aldose reductase (IC_(50) of 0.36-0.46 mg mL~(-1)) and α-glucosidase (IC_(50) of 1.32-1.94 mg mL~(-1)). The 500 g kg~(-1) ethanol extracts also showed α-amylase inhibitory activities (IC_(50) of 70.11-80.22 μg mL~(-1)). Subsequent extracts, prepared further with NaCl and H_2O from precipitates of 800 g kg~(-1) methanol or 500 g kg~(-1) ethanol extracts, exhibited potent α-amylase inhibitory activities (IC_(50) of 17.68-38.68 μg mL~(-1)). A combination of 500 g kg~(-1) ethanol extraction plus a subsequent H_2O extraction produced highest polyphenolics and α-amylase inhibitors. The SA-05 α-amylase inhibitor extracts showed greater inhibitory activities than that of Hwachia. Thus, cranberry bean mutant SA-05 is an advantageous choice for producing anti-hyperglycaemic compounds.