摘要
为提高微生物菌株β-D-葡萄糖醛酸苷酶产酶数量和活性,缩短发酵产酶时间,对一株鸡源饲用枯草芽孢杆菌JY24菌株产β-D-葡萄糖醛酸苷酶的发酵工艺和初步催化转化进行研究。采用单因素试验对枯草芽孢杆菌JY24菌株产β-D-葡萄糖醛酸苷酶的产酶条件及培养基成分进行筛选;采用正交试验对培养基组成进行优化分析,采用HPLC法对酶催化黄芩苷转化试验进行初步研究。试验结果表明,鸡源饲用枯草芽孢杆菌JY24菌株产β-D-葡萄糖醛酸苷酶最佳产酶条件:发酵时间42 h,发酵转速240 r/min,装液量10%,培养基初始pH 7.0,发酵温度35℃,接种量4%;最佳产酶培养基组成:蔗糖8.0 g/L,酵母膏11.0 g/L,磷酸二氢钾0.38 g/L,磷酸氢二钾0.38 g/L,氯化钙0.27 g/L,硝酸钾0.20 g/L,Tween-202.0 mL/L,玉米浆1.0 mL/L,黄芩苷1.5 g/L。在此最佳发酵工艺条件下,JY24菌株发酵液β-D-葡萄糖醛酸苷酶酶活性达935.50 U/mL,较优化前提高25.68倍,发酵产酶时间缩短2.25~12.25 d,酶催化初步研究表明黄芩苷转化率为31.20%。
In order to improve the enzyme quantity and activity from microbial strains,shorten fermentation time of enzyme production,this article aimed to study the optimization of fermentation process and preliminary catalytic conversion ofβ-D-glucuronidase from Bacillus subtilis,JY24 strain.Culture conditions for the production ofβ-D-glucuronidase from Bacillus subtilis JY24 strain were optimized by single factor method;the compositions of culture medium and conversion of baicalin were respectively studied by orthogonal design and HPLC.The result showed that the optimal culture conditions were:fermentation time,42 h;rotational speed,240 r/min;50 mL culture in 500 mL liquid volume;initial culture medium,pH 7.0;temperature,35℃;inoculation amount,4%.The optimal compositions of medium were:sucrose,8.0 g/L;yeast extract,11.0 g/L;KH 2 PO 4,0.38 g/L;K 2 HPO 4,0.38 g/L;CaCl 2,0.27 g/L;KNO 3,0.20 g/L;tween-20,2.0 mL/L;corns steep,1.0 mL/L;baicalin,1.5 g/L.Under the optimized fermentation process,the enzyme activity ofβ-D-glucuronidase of Bacillus subtilis JY24 strain could reach 935.50 U/mL,which was 25.68 times higher than that before optimization,and the fermentation time for enzyme production was greatly shortened by 2.25-12.25 d.The preliminary results of catalytic conversion showed that the conversion rate of baicalin was 31.20%.
作者
高书锋
孔利华
雷平
曾发姣
王升平
龚平
周小玲
刘惠知
GAO Shufeng;KONG Lihua;LEI Ping;ZENG Fajiao;WANG Shengping;GONG Ping;ZHOU Xiaoling;LIU Huizhi(Hunan Institute of Microbiology,Changsha 410009,China)
出处
《生物学杂志》
CAS
CSCD
北大核心
2021年第5期110-115,共6页
Journal of Biology
基金
湖南省自然科学基金项目(2017JJ2166)。
