单宁酶的固定化及其性质的研究

Immobilization of Tannase and Its Characters

采用海藻酸钙凝胶对单宁酶进行固定化 ,酶活力回收率高达 6 0 .6 % .对固定化单宁酶性质研究结果表明 ,以没食子酸丙酯为底物时 ,固定化单宁酶酶促反应的最适 p H为 6 .0 ,最适温度为 5 0℃ .在 p H5 .0 ,5 0℃ ,保温 1h或 p H6 .0 ,2 5℃时 1个月内保持稳定 ,或 p H4.0～ 7.0 ,2 5℃保温 6 h仍有 10 0 %的酶活 .固定化单宁酶处理没食子酸丙酯 2 0 m in,经 18个循环后 ,酶仍不失活 。

Tannase (TA) was immobilized by calcium alginate gel. 60 6% of TA was recovered.Properties of immobilized tannase (ITA) were studied. The results show that ITA is stable in the range of pH 4 0 to 7 0 for 6 hours at 25 ℃ or pH 5 0 for an hour at 50 ℃ or pH 6 0 for an month at 25 ℃. The optimal pH value for reaction was 6 0 with propyl as substrate,and the optimal temperature was 50 ℃.ITA was treated with propyl gallate and retained 100% of its activity after 18 successive hydrolysis cycles at 50 ℃. The stability of ITA is prior to TA.