摘要
为提高解淀粉芽孢杆菌和硫酯酶的产量,试验以活菌量和芽孢量为指标,采用响应面分析方法对解淀粉芽孢杆菌H6的发酵工艺进行了优化,同时应用qPCR法对硫酯酶基因mRNA表达水平和蛋白质活性进行评估,并测定其对玉米赤霉烯酮的降解活性。结果表明:通过单因素试验筛选出培养基组成的最优碳源、氮源、无机盐分别为可溶性淀粉、酵母浸粉、MgSO_(4)。可溶性淀粉浓度、酵母浸粉浓度、发酵时间是发酵的关键因素。培养基和发酵工艺的最优参数为可溶性淀粉32.16 g/L,酵母浸粉16.27 g/L,MgSO_(4) 10.00 g/L,发酵时间39.28 h,初始pH 5.0,接种量1%,摇床转速200 r/min,发酵温度37℃。在摇瓶中解淀粉芽孢杆菌H6活菌生物产量达到6.33×10^(9)CFU/mL,50 L发酵罐验证活菌产量达到1.09×10^(10)CFU/mL。通过响应面法优化了解淀粉芽孢杆菌H6的发酵工艺,与初始培养基相比,发酵水平显著提高(P<0.05),硫酯酶活性显著升高(P<0.05)。
In order to improve the yield of bacteria and thioseterase,the fermentation process of Bacillus amyloliquefaciens H6 was screened and optimized.The nutrient requirements and fermentation conditions of Bacillus amyloliquefaciens H6 were optimized by response surface methodology with viable bacteria count and spore count as indexes.Meanwhile,the mRNA expression level and the recombinant protein activity of thioesterase were also evaluated.The results showed that the optimum carbon source,nitrogen source and inorganic salt screened by single factor experiment were soluble starch,yeast extract powder and MgSO_(4) respectively.The soluble starch concentration,yeast leaching concentration and fermentation time were the key factors of fermentation.The optimal parameters of culture medium and fermentation process were 32.16 g/L soluble starch,16.27 g/L yeast powder,10.00 g/L MgSO_(4),the fermentation time was 39.28 h,the initial pH was 5.0,the inoculation amount was 1%,the rotation speed was 200 r/min,and the fermentation temperature was 37℃.The biological yield of Bacillus amyloliquefaciens H6 reached 6.33×10^(9) CFU/mL by shaking flask and 1.09×10^(10) CFU/mL by 50 L fermenter.The fer⁃mentation process of Bacillus amyloliquefaciens H6 was optimized by response surface optimization.Compared with the initial culture-medium,the fermentation level was significantly increased(P<0.05),and the thioesterase activity was significantly increased(P<0.05).
作者
耿凯伟
李克克
王俊峰
宫玉杰
田亚东
康相涛
王彦彬
孙向丽
GENG Kaiwei;LI Keke;WANG Junfeng;GONG Yujie;TIAN Yadong;KANG Xiangtao;WANG Yanbin;SUN Xiangli(College of Veterinary Medicine,Henan Agricultural University,Henan Zhengzhou 450046,China;Henan Jinbaihe Biotechnology Co.,Ltd.,Henan Anyang 455000,China;College of Animal Science and Technology,Henan Agricultural University,Henan Zhengzhou 450046,China)
出处
《饲料工业》
北大核心
2023年第13期21-30,共10页
Feed Industry
基金
中央引导地方科技发展资金项目[Z20221343015]。
关键词
解淀粉芽孢杆菌H6
硫酯酶
发酵
响应面法优化
玉米赤霉烯酮
Bacillus amyloliquefaciens H6
thioesterase
fermentation
response surface optimization
zearalenone
