添加氨基酸对捷安肽素发酵的影响

在枯草芽孢杆菌ZK(Bacillus subtili)发酵产捷安肽素的过程中,通过Asp、Asn、Glu、Gln、Pro、Ser、Thr、Lys和Tyr等9种氨基酸的单因素添加试验发现,发酵12 h时,160 mg/L的Asp和150 mg/L的Asn对细胞生长和捷安肽素的产量都有明显的促进作用,而200 mg/L的Pro和Lys仅对细胞生长有明显的促进作用;发酵24 h时,Asp、Asn、Glu和Pro等4种氨基酸对捷安肽素的产量有明显的促进作用,最适添加浓度分别为Asp 200 mg/L、Asn 100 mg/L、Pro 100 mg/L、Glu 300 mg/L。在单因素试验基础上,用响应面方法进一步研究了添加氨基酸对细胞生长和产素的促进及其交互作用,并优化了它们的混合添加策略,结果表明,发酵12h时,Asn、Lys和Pro的添加浓度分别为156.3、155.5、153.5 mg/L时,细胞浓度达到3.91×109个/mL,比对照提高37.6%;发酵24 h时,Asn、Glu和Pro的添加浓度分别为145.62、254.78、50.00 mg/L时,捷安肽素效价达到13 118.2 U,比对照提高了28.6%。

Influence of amino acid addition on Jiean-peptide fermentation

The experiment investigated the relationship between the supplication of Asp,Asn,Glu,Gln,Pro,Ser,Lys,Tyr or Thr and the production of Jiean-peptide or the concentration of Bacillus subtilis ZK cell.Asp or Asn not only affected the production of Jiean-peptide but also affected the concentration of Bacillus subtilis ZK cell,and Pro or Lys had obvious effect on the concentration of Bacillus subtilis ZK cell while had little effect on the production of Jiean-peptide.The optimal concentration for Asp,Asn,Pro and Lys were 160 mg/L,150 mg/L,200 mg/L and 200 mg/L at the 12th hour.It provided a significant increase in the production of Jiean-peptide when the concentration for Asp,Asn,Pro and Glu were 200 mg/L,100 mg/L,100 mg/L and 300 mg/L at 24th hour,but the four kinds of acid amino had no effect on the concentration of Bacillus subtilis ZK cell.Based on the single factor experiment,the response surface methodology(RSM) was selected to investigate the coefficient among them.The Jiean-peptide production was 13 118.2 U,increased significantly by 28.6%,when 145.62 mg/L Asn,254.78 mg/L Glu and 50.00 mg/L Pro were addicted to the medium at 12 th hour the the cell concentration of the Bacillus subtilis ZK was 3.91×109/mL,increased by 37.6% when 156.3 mg/L Asn,153.5 mg/L Pro and 155.5 mg/ L Lys were addicted to the medium.