【摘要】 采用酶酸连续降解壳聚糖制备低分子量水溶性壳聚糖。首先确定了单因素降解壳聚糖的最佳技术参数:木瓜蛋白酶降解壳聚糖时最优条件为45℃、2 h;醋酸降解壳聚糖时最优条件为30℃、4 h;盐酸降解壳聚糖最优条件为90℃、8 h;然后根据单因素降解壳聚糖最优条件确定了酶酸连续降解壳聚糖新工艺,并优化反应时间为7 h。在相同条件下,酶酸连用方法最终降解产物的粘度低于单因素降解产物的粘度,产物表面性状有很大不同,分子量由降解前的33 523.14下降到3 134.11。更多还原

【Abstract】 The preparation of low molecular weight chitosan are investigated. The optimal conditions for degradation of chitosan are determined as follows :reaction temperature 45 ℃ and reaction time 2 h by papain; reaction temperature 30 ℃ and reaction time 4 h by hydrochloric acid; reaction temperature 90 ℃ and reaction time 8 h by acetic acid. Then, on the basis of these, the preparation method is set and the reaction time is optimized to 7 h. The experimental results show that, under the same conditions, the viscosity of the final product degraded by both papain and acid is lower than that of final product degraded by papain or acid only. The molecular weight of degraded product decreases from 33 523.14 to 3 134.11.更多还原