纳豆芽孢杆菌Bacillus natto NK4液态发酵产纳豆激酶的工艺优化

Optimization of liquid fermentation condition of Bacillus natto NK4 for nattokinase production

为提高纳豆激酶的产量,采用单因素试验及正交试验对纳豆芽孢杆菌Bacillus natto NK4进行发酵条件优化,获得该菌种液体发酵产酶的最优条件。结果表明,纳豆芽孢杆菌产纳豆激酶最佳的发酵条件为接种量2%,培养基初始pH值6.0,培养温度34℃,发酵时间72 h。此时,纳豆激酶酶活力由848.28 IU/mL提高到1569.31 IU/mL。

To improve the production of nattokinase,single-factor experiments and orthogonal experiments were conducted to optimize the fermentation conditions of Bacillus natto NK4.The optimal conditions for liquid fermentation of this strain were obtained.The results showed that the optimal fermentation conditions for Bacillus natto to produce nattokinase were an inoculum size of 2%,an initial pH of 6.0,a fermentation temperature of 34℃,and a fermentation time of 72.0 h.Under these conditions,the enzyme activity of nattokinase increased from 848.28 IU/mL to 1569.31 IU/mL.