纳豆菌固定化材料优化的研究

Optimized Conditions of Bacillus subtilis Natto Immobilization

为获得固定化纳豆菌材料,以海藻酸钠(SA)和聚乙烯醇(PVA)为包埋材料,采用固定化细胞技术对纳豆菌生产纳豆激酶进行了研究。结果表明:在PVA中加入SA进行细胞包埋可获得渗透性能好强度高的固定化细胞。通过正交试验进一步确定,当PVA的浓度为9%、SA的浓度为1%、硼酸的浓度为5%、CaCl2的浓度为6%时,固定化细胞的强度最好,采用摇床培养可连续发酵使用6次,活性也很高,产生的纳豆激酶酶活溶纤圈直径积达87.69 mm2.15μL-1。

Natto strains NK6 immobilized cells had higher enzyme activity than the free cells, hence immobilization was useful for industrial nattokinase fermentation continuous production. In order to obtain optimized conditions of Bacillus natto immo- bilization. Sodium alginate （SA） and polyvinyl alcohol （PVA） were used as embedding materials in studying immobilization technology to produce nattokinase. The results showed that when PVA added SA were used, immobilized cells had good per- meability and high intensity. Further defined by the orthogonal test showed that when PVA concentration was 9% , SA con- centration was 1% , boric acid concentration was 5% , and CaCl2 concentration was 6% , the immobilized cells could be used 6 batches repeatedly with high activity, resulting in the fibrinolytic activity of nattokinase circle diameter up to 87.69mm2 · 15μL-1.