一株新的短芽孢杆菌低温弹性蛋白酶的发酵优化

Optimization of Fermentation Conditions for Production of A Extracellular Elastase from A Newly Isolated Bacillus brevis

[目的]优化短芽孢杆菌XZE116菌株的培养条件使之产生高活性的胞外弹性蛋白酶。[方法]通过单因子和正交试验对XZE116菌株产胞外弹性蛋白酶的培养基及发酵条件进行优化。[结果]该菌株产酶最佳培养基组成为:葡萄糖0.5%、蔗糖0.1%、干酪素0.5%、酵母膏0.5%,K2HPO40.1%,KH2PO40.5%,MgCl20.01%;最佳发酵条件为:250 ml三角烧瓶中装液量40 ml、接种量5%、摇瓶转速200 r/min、pH 8.4、发酵温度为27℃、发酵时间为72 h。XZE116菌株在最佳培养条件下,该菌株的酶活力提高了1.6倍。[结论]研究可为这株新的短芽孢杆菌进行发酵工业生产提供依据,同时为进一步利用该菌株产生的弹性蛋白酶奠定基础。

[ Objective ] The present work aimed to optimize the culture conditions to produce extracellular elastase by Bacillus brevis XZE116. [ Method] Culture conditions were optimized to produce the extracellular elastase by the single factor and orthogonal tests. [ Result] The opti- mal medium components were： glucose 0.5% , sucrose 0.1% , casein 0.5% , yeast extract 0.5%, K2HPQ 0.1%, KH2PO4 0.5% , MgC12 0.01%. The optimal culture conditions were： 40 ml medium in 250 ml triangular flask, inoculum＇ s volume 5% , shaking speed of 200 r/min, initial pH 8.4, at 27 ℃ for 72 h. The enzyme activity was improved by Mg2 ＋ ; and inhibited by Co2＋ and Zn2 ＋ at 1 mol/L. The en- zyme activity was increased by 160%. [ Conclusion] This study will be helpful to the future commercial development of the new bacteria-based antiviral ribonuclease fermentation process.