Method for preparing chitooligosaccharide based on composite enzyme

Abstract

The application belongs to the technical field of chitosan oligosaccharide preparation, and particularly relates to a method for preparing chitosan oligosaccharide based on a composite enzyme. The application provides a method for preparing chitosan oligosaccharide based on a composite enzyme through a multi-enzyme synergistic system and cooperation of a specific protective agent, wherein chitosanase and chitinase can synergistically cut the beta-1,4 glycosidic bond of chitosan, the molecular weight distribution of the product is controlled, at the same time, the chitinase can also directionally cut the beta-1,4 bond at the end of chitosan, and the papain is used for removing the protein impurities in the chitosan to realize accurate control of the degree of polymerization. In addition, the application specifically designs a specific protective agent matched with the above multi-enzyme synergistic system, the specific protective agent and the multi-enzyme composition jointly act, can significantly reduce the molecular weight distribution width, improve the yield and the DP 4-8 proportion, and at the same time, a physical field ultrasonic assistance is added in the process of enzymatic treatment, further promotes the combination of the substrate and the enzyme, and shortens the reaction time.