明胶-海藻酸钠固定化菊糖果糖转移酶

Effect of immobilization with gelatin and sodium alginate on the inulin fructotransferase

采用明胶和海藻酸钠为包埋载体,进行菊糖果糖转移酶固定化的初步研究,探究明胶与海藻酸钠浓度、Ca Cl2浓度、包埋时间等因素对固定化效果的影响,并对固定化酶的酶学性质进行了研究。结果表明,明胶浓度为20 g/L、海藻酸钠浓度为20 g/L、Ca Cl2浓度为40 g/L、包埋时间5 h,酶的包埋率为95.6%,重复操作8次后相对酶活力保留在50%以上。与游离酶相比,固定化酶的最适反应p H为5.5~6.0,最适反应温度为65~70℃,具有良好的操作稳定性。

Inulin fructotransferase was firstly immobilized using sodium alginate and gelatin as entrapment carri- ers. The effects of several factors such as concentrations of gelatin, sodium alginate and CaC12 and embedding time were explored. The properties of immobilized enzyme were also investigated. The results indicated that the enzyme were best immobilized with 20 g/L gelatin, 20 g/L sodium alginate, 40 g/L CaCI2 for 5 h. The enzyme entrapping rate was 95.6%. The relative enzyme activities were retained over 50% after 8 times of operation. Compared with the free enzyme, the optimum pH value and reaction temperature of immobilized enzyme were 5.5 - 6.0 and 65 - 70℃ , respectively. It showed that immobilized enzyme had good operation stability.