Antinutritional factors in plants diminish the digestive action of stomach enzymes and reduce the accessible supplement for assimilation in the gut. Isolation of a trypsin-chymotrypsin inhibitor from Cyamopsis tetragonoloba seeds is being reported in this paper. The inhibitor was purified by DEAE-cellulose chromatography followed by gel permeation on Sephadex G-75. The inhibitor was found to be of 11 kDa on denaturing polyacrylamide gel electrophoresis and possess the highest inhibitory action at pH 7.5 and 37°C. The isolated inhibitor was found unusually stable at high temperatures and microwave heating. Freshly prepared inhibitor exhibits around 71% inhibition on incubation for 30 min in the temperature range from 20°C to 100°C. The inhibitory action was influenced in the presence of oxidizing and reducing agents. This inhibitor was stable in the presence of oxidizers dimethyl sulfoxide, hydrogen peroxide, and sodium hypochlorite. The effect of stabilizers shows that CaCl2 and glycerol support enhancement of the inhibitory activity. The inhibitor was also checked for antimicrobial activities. Inhibitor did not show any antimicrobial activity against Staphylococcus aureus, Escherichia coli, Klebsiella, Pseudomonas, Salmonella typhi, and Proteus.
Key words: Cyamopsis tetragonoloba, Trypsin-Chymotrypsin inhibitor, Antioxidant nature, Thermostable