摘要
木瓜蛋白酶经戊二醛固定于自制的甲壳质上制成固定化木瓜蛋白酶 ,其水解甲壳胺的最佳条件是 :4 5℃ ,pH 4 .0的 1%的甲壳胺溶液 (醋酸缓冲液配置 ) ,酶 /底物比 1∶3.5 (质量比 )。震荡反应 2 4h后 ,用超滤器分离不同分子量的甲壳胺低聚糖产物 ,结果产物中分子量小于 10 0 0 0的甲壳胺低聚糖得率约为 4 5 .5 5 % ,分子量小于 5 0 0 0的约为 34 .0 % ,优于游离木瓜蛋白酶水解甲壳胺的效果。此固定化酶可反复使用至少 10次以上 ,总反应时间达 192h ,提高了酶的使用效率和酶解效果。
Glutaric aldehyde as cross linking agent was used to immobilize papain on chitin. The optimum conditions for depolymerizing chitosan by the immobilized papain were as follows: temperature 45℃, pH 4.0, and the weight ratio of immobilized papain to substrate was 1∶3.5. After 24 h's reaction with stirring, the ultrafiltration was used to isolate the chitooligomers into different ranges of molecular weight. The yield rate of chitooligomers with molecular weight below 10 000 was 45.55% to total substrate, and 34% below molecular weight 5 000. The immobilized papain could be used at least 10 times repeatedly, and the total reaction time was more than 192 h, which is longer than 182 h reported previously. When the free papain was used to depolymerize chitosan, the yield rate of chitooligomers with molecular weight below 10 000 was 38.32%. The free papain could be used only once. The result indicated that the depolymerization efficiency of immobilized papain was obviously higher than that of free papain.
出处
《中国水产科学》
CAS
CSCD
北大核心
2001年第3期77-80,共4页
Journal of Fishery Sciences of China
基金
高等学校骨干教师资助计划项目
关键词
木瓜蛋白酶
酶固定化
甲壳胺
水解
低聚糖
papain
enzyme immobilization
chitosan
depolymerization
chtooligomers
