Enzymatic Degradation Of Chitosan

The characteristics of some non-specific enzymes (Trypsin, Lysozyme, Cellulase, Amylase, which were from commercial enzymatic reagents.) on degrading chitosan were studied in this paper to find a better way for making chitosan oligomers. A pilot study was also done on the selection of microorganisms which could synthesize chitosanase effectively. The results showed that:1,For the same substrate of chitosan which was of 83.97% deacetylated degree, the Trypsin and Lysozyme showed different hydrolyzing characteristics. The optimum reaction conditions for trypsin were as following: pH value of 5.0, reaction temperature of 30℃, V_max of 8.03 mg·L^-1·min^-1 and K_m of 9.54g·L^-1, meanwhile the same parameters for lysozyme were pH4.0, 60℃, V_max 34.6 mg·L^-1·mm^-1, and K_m 5.46g L^-1 respectively; meaning that the appetency of lysozyme to chitosan was higher than lrypsin.2, When degrading the chitosan which was of 95.31% deacetylated degree, the cellulase and amylase had the same optimum reaction pH of 5.4 and the same optimum temperature of 50℃, while having different V_max and K_m . The V_max and K_m of cellulase were 1.24 mg·L^-1·min^-1 and 1.68g·L^-1 respectively, vs. that of amylase: 1.22 mg·L^-1·min^-1 and 0.117g· L^-1, also indicating that the Amylase had higher appetency to chitosan than Cellulase.