In vitro Simulation of Gastric and Pancreatic Phase Digestion of Meat and Bone Meal – Studies of Pepsin Autolysis

North Carolina State University Swine Nutrition Research from 2001. It was demonstrated that the deactivation of pepsin took the form of autolysis. The more unfavorable the condition (less favorable pH, higher concentration), the less autolysis and the more denaturation occurred. The autolysis of pepsin was faster at more favorable pH (pH 2.0 versus pH 4.0). The higher the concentration, the slower the autolysis was. Both pH and concentration had significant effects on the maximal degree of autolysis. However, the degree of autolysis varied within a narrow range. On average, the maximal degree of autolysis was 11.0 %, and pepsin autolysate peptide contained 9.1 amino acid residual. The autolysis of pepsin at 0.5 mg/ml in pH 4.0 buffer became sigmoidal rather than exponential. No substrate protection was found.