纤维素酶-过氧化氢降解法制备低聚壳聚糖的研究

STUDY ON PREPARATION OF LOW-MOLECULAR WEIGHT CHITOSAN BY CELLULAS-H_2O_2 DEGRADATION

利用纤维素酶-H_2O_2降解法制备低分子量壳聚糖,分别研究了pH值、温度、酶浓度、H_2O_2加入量及反应时间等因素对产品的收率及平均分子量的影响。结果表明最佳反应条件为:pH为5.6、酶/糖为0.1、反应温度为54℃、反应时间为6 h。在反应结束前0.5h加入一定量H_2O_2进行氧化降解可以得到平均分子量为1500的低聚壳聚糖。而且由于H_2O_2的作用产物的颜色较浅。

In this paper the preparation of low-molecular weight chitosan by cellulas-H2O2 degradation was studied. The effects of pH, temperature, cellulas/chitosan, reaction time, and added amount of H2O2 on the yield and average molecular weight of product were developed. The results showed that the lowest average molecular weight of chitosan required only by hydrolysis reaction of cellulas is 4 000. The optimal reaction condition is that pH 5. 6, cellulas/chitosan 0. 1, temperature 54 C and reaction time 6 h. If more lower molecular weight chitosans were prepared, a proper amount of H2O2 should be added at 0. 5 h before the reaction finished. The low molecular weight and light color chitosan, which average molecular weight is 1 500, were obtained.