Influence factors of the chitosan degradation by pawpaw protease

Abstract

The pawpaw protease is used to degrade chitosan to prepare a low molecular weight chitosan-reducing sugar.The effect of temperature, pH value, reaction time and enzyme addition on the degradation of chitosan was investigated by single factor experiment with the reducing sugar concentration of the degradation solution as the index. The experimental results show that with the increase of the amount of enzyme added and the prolongation of the reaction time, and the degradation rate of chitosan increased and the concentration of reducing sugar increased. As the increase of pH and reaction temperature, the concentration of reducing sugar first increases and then decreases. The optimal conditions for chitosan degradation is 4.1 of the pH value, 42 °C of the reaction temperature, 1.4 h of the reaction time, and enzyme addition amount is 30 U/mg. Under the above conditions, the reducing sugar concentration reaches 1.57 g/L, and the rate is 15.7%.