In vitro study on -amylase inhibitory activity of an Indian medicinal plant, Phyllanthus amarus

Objective : The objective of this study was to evaluate the a-amylase inhibitory activity of different extracts of Phyllanthus amarus against porcine pancreatic amylase in vitro. Materials and Methods : The plant extracts were prepared sequentially with ethanol, chloroform, and hexane. Each extract was evaporated using rotary evaporator, under reduced pressure. Different concentrations (10, 20, 40, 60, 80, and 100 g/mL) of each extract were made by using dimethyl sulfoxide (DMSO) and subjected to a-amylase inhibitory assay using starch azure as a substrate. The absorbance was read at 595 nm using spectrophotometer. Using this method, the percentage of a-amylase inhibitory activity and IC 50 values of each extract was calculated. Results : The chloroform extract failed to inhibit a-amylase activity. However, the ethanol and hexane extracts of P. amarus exhibited appreciable a-amylase inhibitory activity with an IC50 values 36.05 4.01 g/mL and 48.92 3.43 g/mL, respectively, when compared with acarbose (IC 50 value 83.33 0.34 g/mL). Conclusion : This study supports the ayurvedic concept that ethanol and hexane extracts of P. amarus exhibit considerable a-amylase inhibitory activities. Further, this study supports its usage in ethnomedicines for management of diabetes.