Single Factor Experimental Study on The Preparation of Chitosan Oligosaccharide

Abstract

Chitosan oligosaccharides were prepared by papain enzymatic hydrolysis. The single factor experiments were experimentalized to study the degradation of chitosan by papains. The concentration of reducing sugar and the yield of reducing sugar in the enzymatic hydrolysate were used as reference indicators. The effects of reaction time, pH, reaction temperature, amount of enzyme and substrate concentration were discussed. The results showed that the concentration of reducing sugar increased at first and then decreased with the increase of pH value and reaction temperature. With the prolonging of reaction time, the reaction slowed down and the enzymatic hydrolysis speed slowed down. The increase of the amount of enzyme promoted the reaction rate, and the concentration of reducing sugar also increased. The change of substrate concentration also led to the change of reducing sugar yield. The optimal conditions were obtained by the single factor experiment. When 50 °C of the reaction temperature, 5.0 of pH, 60 min of reaction time, substrate concentration reached 1.75% and the amount of enzyme reached 1:10. At the above condition, the concentration of chitosan oligosaccharide was 4.33 mg/mL and the chitosan oligosaccharide yield was up to 24.73%.