Exceptional Stability of Kidney Bean Inhibitor to Temperature and Pepsin Digestion

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IPFW Research and Creative Symposium

Conference Location

IPFW, Fort Wayne


Background Information: Proteins are one of the most important compounds present in living organisms. Humans are believed to contain about 25,000 different proteins, each involved in a specific function. The function of proteins is strongly dependent on their structure. Exposing the proteins to external factors such as high temperature (~100oC) or to the digestive enzyme of the stomach (pepsin) generally affect their structure and hence their function. In this poster we present our results on the effect of heat and pepsin digestion on the function of a kidney bean protein. The kidney bean protein we have studied functions as an inhibitor of the intestinal enzymes such as trypsin and chymotrypsin.

Aim: The main aim of this study was to investigate the effect of temperature and pepsin digestion on the chymotrypsin and trypsin inhibitory activity of kidney bean inhibitors.

Experiments and Results: The kidney bean extract was separately exposed to a temperature of 100oC for up to 3 hours and to pepsin digestion up to one week. The heat treated and pepsin digested samples of kidney bean extract were analyzed by the techniques of gel filtration and electrophoresis and their inhibitory activity against chymotrypsin and trypsin were determined by the spectrophotometric technique. The results suggest that the activity of kidney bean inhibitor is unaffected up to one hour of heating and up to several hours of digestion with pepsin. The main conclusion of this study is the exceptional stability of kidney bean inhibitor to heat and pepsin digestion.


Protease Inhibitors, Red Kidney bean, Pepsin Digestion, Chymotrypsin Inhibition, Trypsin Inhibition


Biochemistry | Chemistry

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