改良甜菊苷不良味质生物酶的固定化研究

Study on the immobilization of CGTase Enzyme

目的优选环糊精葡糖基转移酶的最佳固定化工艺,并对固定化酶的性质进行考察。方法以生物酶活力为指标,对影响生物酶活性的海藻酸钠、明胶、固定化酶液量、固定化时间、氯化钙及戊二醛进行了考查,并对固定化前后酶液的性质进行了比较。结果海藻酸钠浓度5%,明胶浓度4%,固定化酶液量占海藻酸钠、明胶总量的1%,固定化时间1h,氯化钙浓度5%,戊二醛浓度0.5%时固定化酶活力最强,固定化酶的适宜作用温度范围、pH值范围均比游离酶宽,固定化酶的热稳定性高于游离酶,重复使用时批次操作也显示出较好的稳定性。结论该方法简单、准确、可行,具有实用价值。

OBJECTIVE To optimize the optimal immobilization craft of CGTase,and investigate the characteristic of the immolilized enzyme.METHODS Taking biological enzyme activity as the index,to examine influencing factors that sodium polymannuronate,gelatin,amount of immobilized enzymes solution,immobilized time,calcium chloride and glutaral.And compared the properties of enzyme fluid before and after immobilization.RESULTS When density of sodium polymannuronate was 5% and gelatin was 4%,amount of immobilized enzymes solution held 1% of total amount of sodium polymannuronate and gelatin,immobilized time was 1h,density of calcium chloride was 5% and glutaral was 0.5%,the activity of immobilized enzymes was strongest.Compared with free enzymes,the suitable range of temperature and pH value of immobilized CGTase were respectively wide.the thermostability of immobilized CGTase was better than free enzymes.After several repeated operations,the relative activity of immobilized enzyme showed high operational stability.CONCLUSION This method was simple,precise,feasible and had practical value.