α-乙酰乳酸脱羧酶的3种固定化方法的比较

Comparison of three methods for ALDC immobilization

用磁性淀粉微球作为载体 ,采用溴化氰活化法、戊二醛交联法及物理吸附法固定化α 乙酰乳酸脱羧酶 (ALDC) ,并对它的理化性质进行了对比 ,得到的结果是戊二醛交联法固定法ALDC的各种理化性质最为理想 ,它的总活力为 1 660U/g ,蛋白载量为 1 2 3 .1 7mg/ g ,比活为 1 6.4 8U/mg ,活性回收率为 1 4 .92 %。它的催化最适温度为 3 0℃ ,最适pH为 5 ,连续 1 0次催化底物后其活力仍保持 77.2 % ,且其半衰期为 2 1 6d。

By the methods of CNBr-activating, physical-absorbing, and cross-linking with glutaldehyde,we immobilize ALDC onto the magnetic starch functional composite micro-sphere. Compared with other methods, the last one is the best. Its characteristic values are listed as follows: mass activity, 1?660?U/g; protein binding, 123.17?mg/g; specific activity, 16.48?U/mg; activity retentions, 14.92%. The optimum temperature is 30?℃ and optimum pH value, 5. After reducing the substrate ten times continually, it still keeps 77.2% in activity, 216-day for half-life.