苹果渣固态发酵产纳豆激酶的工艺优化

Optimization of Fermentation Conditions for Nattokinase Production in Solid-state Fermentation by Bacillus subtilis Natto Using Apple Pomace as Substrate

在单因素试验基础上,确定尿素添加量、培养基加水量、氧化钙添加量为影响酶产率的重要因素,应用响应面分析法对固态发酵苹果渣产纳豆激酶的工艺条件进行优化。优化得到最佳工艺条件为:尿素添加量2.58%、培养基加水量84.06mL、氧化钙添加量2.65%。采用最优化条件进行实验,结果表明:纳豆激酶产率可达到2150IU/g,比单因素试验的最高酶产率(1680IU/g)提高了27.98%。以廉价的工农业废料作为基本培养基获得了有较高酶活的产品,经济优势明显。

On the basis of the results of one-factor-at-a-time experiments,urea concentration,water amount and calcium oxide concentration were determined to be the most important factors affecting on nattokinase production.Subsequently,response surface methodology was used to optimize these factors.The results showed that the optimal values of urea concentration,water amount and calcium oxide concentration were 2.58%,84.06 mL and 2.65%,respectively.Under these conditions,the maximum nattokinase yield was 2150 IU/g,27.98% higher than that obtained in one-factor-at-a-time experiments（only 1680 IU/g）.The achievement of a high nattokinase activity using apple pomace,a low-cost industrial and agricultural waste as fermentation substrate demonstrates obvious economic advantages.