海藻酸钠、卡拉胶联合固定化α-淀粉酶特性研究

Study on Immobilized Alpha-amylase Property with Alginate and Gum Kala Mixture

以海藻酸钠、卡拉胶共混包埋制备固定化α-淀粉酶,并对α-淀粉酶固定化条件和固定化酶性能进行了探讨。研究表明:在海藻酸钠浓度3.0%、卡拉胶浓度1.0%、酶浓度18g/L、氯化钙浓度0.8%条件下,可以获得最佳的固定化效果,固定化酶活力为139.66U/g.min,活力回收率为55.70%;与游离酶相比,制备固定化酶的最适酶促反应pH值由7.0降至6.0,最适酶促反应温度由60℃升至70℃,其作用温度范围、pH值范围均比游离酶范围宽;固定化酶在连续操作5次后仍显示出良好的活性,固定化酶的耐热性也显著提高。

Alpha-amylase was immobilized by encapsulating in hydrogel beads prepared with alginate-carrageenan.Their mobilization conditions and partial properties of immobilized enzyme were investigated.The best efficiency of immobilization could be obtained under the condition that the concentration of alginate was 3.0%、carrageenan was 1.0% 、Alpha-amylase was 18g/L and CaC12 was 0.8% and the immobilized enzyme activity was 139.66 U/g.min.The recovery of activity was 55.70%.Compared with the free enzyme,the optimum pH value and temperature of immobilized alpha-amylase were shifted from 7.0 to 6.0 and from 60℃ to 70℃ respectively.It showed a wider range of reaction pH value and temperature than the free enzyme.The thermostability of immobilized alpha-amylase was better than native enzymes.After 5 times repeated batch operations,the relative activity of immobilized enzyme was about 65%,showing a high operational stability.