高产纳豆激酶突变菌株产酶条件的研究

Optimation on Fermentation Conditions of a High-yield Nattokinase Mutant

为了获得最佳产酶条件,通过研究不同碳源(葡萄糖、木糖、麦芽糖、蔗糖、淀粉),氮源(牛肉膏、蛋白胨、大豆蛋白胨、酵母膏、硫酸铵),碳氮浓度比和无机离子组成的培养基发酵,利用纤维蛋白平板法测定纳豆激酶的活性。得到纳豆激酶的最佳产酶条件为:1.5%蛋白胨,1.5%麦芽糖,0.05%硫酸镁,0.2%氯化钙,0.2%磷酸二氢钠和0.1%磷酸氢二钠;碳氮浓度比为1∶1。

In order to obtain optimal conditions for nattokinase production,the influencing factors of carbon source（glucose,sucrose）,nitrogen source（beef extract,peptone,soy peptone,yeast extract,ammonia sulfate）,C/N concentration and inorganic ions composition were investigated by fermentation culture and the activity of nattokinase was determined by fibrin plate method.Results showed that the best condition of enzyme production was 1.5% peptone,1.5% maltose,0.05% MgSO4,0.2%CaCl2,0.2%NaH2PO4 and 0.1%Na2HPO4,with the carbon and nitrogen concentration ratio of 1∶1.