张弓老酒大曲中高产纤维素酶菌株的分离鉴定

Isolation and Identification of High-yield Cellulase Strains from ZhangGongLaoJiu Daqu

本研究以羧甲基纤维素钠为唯一碳源作初筛培养基,利用刚果红变色圈法从张弓老酒酒业有限公司大曲中分离得到一株高产的纤维素酶细菌D39。经细菌形态学观察,生理生化实验,并结合16S rDNA序列分析,初步鉴定其为枯草芽孢杆菌(Bacillus subtilis)。并通过单因素试验和响应面试验优化确定最佳产酶条件为:接种量4%,培养时间3 d,pH值4。优化后其酶活为1014 U/mL,与优化前相比产酶能力提高1.3倍。本研究结果可为后续提高酿酒原料利用率,缩短发酵时间,以及控制大曲发酵培养工艺提供参考依据。

In this experiment,sodium carboxymethyl cellulose was used as the sole carbon source as the primary screening medium.A high-yield cellulase bacterium D39 was isolated from the ZhangGongLaoJiu Daqu by Congo red color circle method.Through bacterial morphology,physiological and biochemical experiments,combined with 16 S rDNA sequence analysis,D39 was initially identified as Bacillus subtilis.The optimal fermentation conditions were determined by single factor and response surface test optimization:inoculation amount 4%,culture time 3 d,pH=4.After optimization,the enzyme activity was 1014 U/mL,which was 1.3 times higher than that before optimization.The results of this study could provide references for further improving the utilization rate of brewing materials,shortening the fermentation time,and controlling the fermentation culture technology of Daqu.