Purification and characterization of alpha‐amylase inhibitor from the seeds of underutilized legume,Mucuna pruriens

Abstract

An α-amylase inhibitor (EC 3.2.1.1) was purified by buffer extraction, ammonium sulfate fractionation, CM-cellulose, and sephadex G-75 chromatography from the soaked seeds of Mucuna pruriens. The molecular weight determined by gel permeation chromatography on Sephadex G-100 and SDS-PAGE, both in the presence and absence of 2-mercaptoethanol, was found to be 27.24 kDa and 25.6 kDa, respectively. The purified Mucuna pruriens amylase inhibitor showed a specific inhibitor activity of 61.18, fold purity of 36.68, and the yield obtained was 14.01%. The purified amylase inhibitor was found to be heat-stable and retained 80.50% activity at 65°C. Inhibitor was found to have pH optima of 6.9. Hundred percent zone of inhibition was observed when added on the plated organisms of purified inhibitor. Purified amylase inhibitor was found to inhibit the activity of human salivary α-amylase. Inhibitory activity of α-amylase inhibitor against mammalian amylases could suggest its potential in treatment of diabetes and cure of nutritional problems, which results in obesity. Practical applications Purified amylase inhibitor was found to inhibit the activity of human salivary α-amylase. The potential of this inhibitory activity from α-amylase inhibitors, especially in the mammalian α-amylase, could play an important role in the management of nutritional and diabetes-related disorders. Mucuna, an underutilized legume found in tropical region and also cultivated as food by various tribal's in Asia and Africa can be used as a potential source for extraction of these beneficiary protease inhibitors, which in turn finds its applications in various human therapeutic and/or disorder management.