解淀粉芽抱杆菌产碱性蛋白酶发酵条件的优化

Optimization of Fermentation Medium for Production of Alkaline Protease by Bacillus amyloliquefaciens

通过单因素试验对解淀粉芽孢杆菌菌株发酵产碱性蛋白酶的培养基组分及培养条件进行优化。利用单因素实验确定了产酶的最优培养基:玉米淀粉30g/L,棉籽蛋白粉70g/L,氯化钙3.89g/L,硫酸镁4.21g/L,磷酸氢二钠85.18g/L,磷酸二氢钾81.65g/L;同时对控制工艺进行优化,得到最优发酵条件:接种量4%,温度38T,pH控制7.3,罐压0.05Mpa,通过调整转速和风量,使溶氧水平维持在10%-20%。采用连续补料的方式,补麦芽糖浆控制发酵液的还原糖含量在20g/100g左右;优化后的补料培养基配方为:40%浓度的麦芽糖浆。发酵产酶周期:100h左右。经过上述一系列的优化后,最终酶活达到65200U/mL,较初始配方酶活15680U/mL提高了3.16倍。

The medium components and culture conditions for Bacillus amyloliquefacienswere optimized by single-factor to increase the production of alkaline protease.The results showedthat the optimized medium consisted of soybean powder 30g/L,cottonsced protein powder 70g/L,CaCl1,3.89g/L,MgSO,4.21g/L,Na,HPO,85.18g/L and KH,PO.81.65g/L;At the same time,the control process was optimized,culture conditions were 38℃,4%,7.3 and 0.05MPa for temperature,innoculation amount,pH respectively and tank pressure.By adjusting the speed and airvolume,the dissolved oxygen level is maintained at 10%-20%.The results showed that the con-lent of reducing sugar in fermentation broth was about 20g/100g by contiuous feeding,and theoptimized medium formula was maltose syrup with 40%concentration.The fermentation cycle wasabout 100 h.After a series of optimization,the final enzyme activity reached65200 U/ml,whichwas 3.16 times higher than that of 15680 U/ml.