纳豆激酶高产菌株筛选及发酵条件优化

Selection of high Nattokinase-producing Strains and Optimization of the Fermentation Conditions

摘要:

本实验对日本产优质纳豆中分离纯化得到的15株纳豆激酶菌株进行了研究。通过对其产纳豆激酶能力的测试，筛选出1 mL发酵液产酶为900 IU的N-15株；然后通过单因素试验和正交试验，最终确定其最佳培养条件：培养基由2%蔗糖和2%豆粕组成，发酵温度为37 ℃，起始pH为7；用此优化培养基发酵菌株，菌株产酶量为1033 IU/mL，比优化前有显著的提高。

Abstract:

Fifteen Nattokinase-producing strains separated from Japanese food-natto were investigated in this study. The strain N-15 was selected from the examined striains for its high level of nattokinase-producing activity (900 IU/mL). The fermention conditions of the strain N-15 for the nattokinase production were optimized by single factor and orthogonal tests. It was found that the optimal soybean residue content, sucrose content, incubation temperature and the original pH value were 20%, 2%, 37 ℃ and 7.0, respectively. Under the optimized fermentation conditions, Nattokinase was produced with a high activity level of 1033 IU/mL.