重组表达D-泛解酸内酯水解酶乳酸克鲁维酵母的发酵工艺优化  

Optimized fermentation condition for production of D-lactonohydrolase in a Kluyveromyces lactis recombinant

作　　者：谢颂洋 顾正华 郭自涛 朱慧霞 时祎 辛瑜 张梁 XIE Songyang;GU Zhenghua;GUO Zitao;ZHU Huixia;SHI Yi;XIN Yu;ZHANG Liang(National Engineering Laboratory for Cereal Fermentation Technology,Jiangnan University,Wuxi 214122,China;State Key Laboratory of Pulp and Paper Engineering,South China University of Technology,Guangzhou 510640,China)

机构地区：[1]粮食发酵工艺与技术国家工程实验室(江南大学),江苏无锡214122 [2]制浆造纸工程国家重点实验室(华南理工大学),广东广州510640

出　　处：《食品与发酵工业》2021年第23期38-45,共8页Food and Fermentation Industries

基　　金：江苏省科技计划项目(BE2018055)。

摘　　要：以前期构建的重组表达D-泛解酸内酯水解酶的乳酸克鲁维酵母(Kluyveromyces lactis)GG799为对象,在5 L发酵罐中,基于考察pH、搅拌转速、接种量3种单因素条件对产酶的影响结果,进一步优化补料策略,初步确定了促进重组D-泛解酸内酯水解酶高效表达的补料发酵方式。单因素条件研究结果表明,当pH 6.0、搅拌转速300 r/min、接种量2%时,可以获得最高表达水平,酶活力达5.12 U/mL,较摇瓶最佳结果提高了2倍。补料发酵研究表明,当通过补料维持发酵液恒糖质量浓度为5 g/L时,酶活力可达到8.20 U/mL,较分批发酵酶活力提高了60.1%;当分批发酵结束后,以恒速5 g/h进行补料,酶活力最高可达10.70 U/mL,较恒糖补料方式酶活力提高了30.5%,较分批发酵酶活力提高了98.6%。通过分批发酵和补料分批发酵的研究,显著提高了D-泛解酸内酯水解酶的酶活力,为进一步放大生产奠定了基础。A recombinant Kluyveromyces lactis GG799 was applied for the expression of D-lactonohydrolase.The effects of pH,agitation speed,and inoculum volume on batch fermentation of the enzyme was investigated in a 5 L fermenter.Thereafter,the fed strategy was optimized.The results indicated that the highest enzyme activity could be achieved at 5.12 U/mL under the condition of pH 6.0,300 r/min and 2%of inoculum volume,which was 2 times higher than that of the shaking flask.For the optimization of the feeding strategy,the enzyme activity could reach 8.20 U/mL when the concentration of glucose was maintained at 5 g/L during fermentation,which was 60.1%higher than that was acquired at the batch fermentation.When controlling the supplement of glucose at a rate of 5 g/h after the end of batch fermentation,the highest enzyme activity could be achieved at 10.70 U/mL which was improved by 30.5%and 98.6%compared with that of constant glucose concentration fermentation and batch fermentation,respectively.The research provided a basis for the scale-up production of D-lactonohydrolase.

关 键 词：D-泛解酸内酯水解酶 搅拌转速 接种量 分批发酵 补料发酵 

分 类 号：TQ925[轻工技术与工程—发酵工程]