豆粕固态发酵产纳豆激酶工艺条件研究

摘要

In order to improve the utilization ratio of agricultural byproduct and produce high valueadded bioconversion,soy-bean meal and wheat bran were used as solid medium,Bacillus Subtilis KC02 was used as the producing strain,so as to improve the enzyme activity of nattokinaseby optimizingthe culture medium composition and fermentation condition.The processing con-ditions were optimizd by single factor experiment and orthogonal experiment as follows:themass ratio of soybean meal and w heat bran 5:1,the additive amount of KCl 4%,the fermentation pH value 7.6,the fermentation temperature 37℃,and the fermentation time 36 h.Under this conditions,the average enzyme activity of nattokinase was as high as 6642 U/(g dry soy-bean meal).Compared with traditional soybean solid fermentation,the average enzyme activity of nattokinase in this study was significantly improved.At the same time,the experimental results showed that KCl played a positive role in the process of fer-mentation,and improvedthe average fermatationenzyme activity of thesoybean meal solid medium.%为提升农副产品利用率,生产高附加值生物转化物,本研究利用豆粕、麸皮等农副产品制成固体培养基,以枯草芽孢杆菌KC02为发酵剂,通过优化培养基组成成分和发酵条件,达到提高纳豆激酶酶活力的目的.通过实验,发现当豆粕与麸皮的质量比为5:1,KCl的添加量为4.0%,发酵pH值为7.6,发酵温度为37℃,发酵时间为36 h时,纳豆激酶平均酶活力最高,达6642 U/(g·干豆粕).与传统的大豆固态发酵相比,本研究的纳豆激酶平均酶活显著提高.同时,实验结果表明KCl在发酵产酶的过程中起到了积极作用,提高了豆粕固态培养基的发酵平均酶活.