非专一性酶纤维素酶降解壳聚糖的研究  

STUDY ON THE DEGRADATION OF CHITOSAN WITH NON-SPECIFIC CELLULASE

作　　者：谢宇[1] 胡立明[2] 

机构地区：[1]南昌航空大学环境与化学工程学院,江西南昌330063 [2]徐州空军学院航空军需系,江苏徐州221006

出　　处：《河南工业大学学报（自然科学版）》2008年第3期47-50,共4页Journal of Henan University of Technology：Natural Science Edition

基　　金：江西省自然科学基金(0620071);江西省教育厅科技项目(赣教技字[2007]168号);南昌航空大学科研基金(EA200502138)

摘　　要：采用非专一性酶纤维素酶降解壳聚糖，探讨了不同条件对壳聚糖降解的影响．结果表明：在pH4．0～8．0、温度40～50℃、壳聚糖与酶比值为5：1～20：1范围内，该酶能达到较好的降解效果，在pH5．0、温度50℃、壳聚糖与酶比值为10：1的条件下，降解5min、30min、60min和240min，壳聚糖的平均相对分子质量从酶解前的5．18×10^5分别降到8．58×10^4、7．02×10^4、5．23×10^4和2．44×10^4，降解率分别为初始值的16．5％、13．5％、10．9％和4．7％．从降解情况可以得到酶降解过程中的几个特点：水解初期，溶液粘度迅速下降，说明酶以内切方式作用；提高酶浓度可加快反应速度．The preparation of low-molecular-weight chitosan with cellulase was studied. The effects of different conditions on the degradation of chitosan were investigated. The optimum degradation conditions of cellulase were as follows： pH4.0 - 8.0, 40 - 55℃ , the ratio of chitosan to cellulase is 5：1-20： 1. On the condition of pH5.0, 50℃ and the 10：1 （ the ratio of chitosan to cellulase） , chitosan was degraded for 5 minutes, 30minutes, 60 minutes and 240 minutes respectively, its average molecular weight was about 8.58×10^4 ,7.02 ×10^4,5. 23×10^4 and 2.44×10^4. Compared with chitosan of average molecular weight 5.18×10^5 before enzymatic degradation, cellulase had relatively apparent effect on degradation. The rates of degradation were 16.5% ,13.5% ,10.9% and 4.7% in contrast to the initial molecular weight. From degradation some traits can be concluded in the course of enzymatic degradation ： the viscidity of solution declines quickly in the initial stage of hydrolysis, which suggests that cellulase functions by the way of endo-cut; Increasing the concentration of enzyme will increase the speed of reaction.

关 键 词：壳聚糖 纤维素酶 降解 低相对分子质量壳聚糖 

分 类 号：TS201.3[轻工技术与工程—食品科学]