摘要
从 8种载体材料中选取自制的氨基含量约 2 .878mmol/ g的甲壳质作为固定化载体 ,采用吸附交联法 ,以戊二醛为交联剂 ,对木瓜蛋白酶进行固定化。 17.5 mg/ g的固定化酶 /载体比例 ,p H6 .5 ,5℃下 ,先吸附 10 min,再以 0 .7%的戊二醛终浓度交联 12 h,所得固定化酶酶活回收可达5 2 .0 % ,酶活力为 3.5 4 U / g。固定化酶在 6 5℃以下 ,溶液酶在 5 5℃以下稳定 ;固定化酶在 p H7.0以下稳定 ,溶液酶在 p H6 .0以下稳定 ;5℃条件下 ,固定化酶贮藏半衰期为 183d;以酪蛋白为底物 ,固定化酶的操作半衰期可达 2 7d。用固定化酶水解甲壳胺 ,产物分子量小于 10 0 0 0的甲壳胺低聚糖得率约为 4 5 .5 5 %。
Deacetylated chitin was chosen as support from 8 carrier materials, and glutaraldehyde as crosslinking agent to prepare immobilize d papain. The optimum conditions for immobilization were as follows: the ratio o f enzyme and carrier was 17.5mg/g; pH, 6.5; temp. 5℃;adsorption time was 10min; the final concentration of glutaraldehyde was 0.7% and crosslinking time was 12 h.The activity of the immobilized papain prepared under the optimal conditions was 3.80 Unit/g, the ratio of activity recovery was 52%.The stability of the imm obilized papain was obviously increased comparing with that of soluble papain. S oluble papain was stable under 55℃,pH6.0 while the immobilized papain was still stable under 65℃, pH7.0. The half-life time of immobilized papain stored at 5 ℃ was 183 days, and the operation half-life time was 27 days. Using the immobi lized papain to depolymerize chitosan, the yield of chitooligomers with molecula r mass under 10,000 was 45.55%. The result was better than that of soluble papai n.
出处
《青岛海洋大学学报（自然科学版）》
CSCD
北大核心
2001年第5期689-694,共6页
Journal of Ocean University of Qingdao
基金
高等学校骨干教师资助计划项目 (甲壳胺低聚糖生物法制备及其抗氧化的研究 )
