氨基酸补料对伊枯草菌素A发酵的影响

Influences of amino acid addition on iturin A fermentation

对枯草芽胞杆菌(Bacillus subtilis ZK8)进行4种不同工艺(分批发酵和3种氨基酸浓度的补料-分批发酵)的发酵,测定并分析了发酵过程中各时间点样品中菌量、伊枯草菌素A(iturin A)的效价、还原糖、总氮及16种游离氨基酸的含量及变化趋势。结果表明,在工艺2(补料浓度分别为天冬氨酸55mg/L,谷氨酸12mg/L,脯氨酸6mg/L)发酵条件下,枯草芽胞杆菌ZK8菌量最高,达2.163×1010个/mL,比分批发酵(对照组)提高9.5%;在工艺1(补料浓度分别为天冬氨酸50mg/L,谷氨酸9mg/L,脯氨酸5mg/L)发酵条件下,iturin A效价最高,达20 101.1U,比对照提高了93.94%。

Batch and fed-batch fermentation of Bacillus subtilis ZK8 were carried out to investigate the effects of amino acid addition on iturin A fermentation.Biomass,potency of iturin A,reducing sugar,total nitrogen and 16 free amino acid concentrations were detected and analyzed during 4 different fermentation processes.In fed-batch fermentation,the highest biomass,2.163 × 1010 cells/mL,was achieved in process 2 with Asp,Glu and Pro at 55 mg/L,12 mg/L and 6 mg/L,respectively,and the biomass increased by 9.5％ compared with batch fermentation.The maximum potency reached 20 101.1 U in process 1 when Asp,Glu and Pro was added at 50 mg/L,9 mg/L and 5 mg/L,respectively,and the potency was raised by 93.94％ in comparison with batch fermentation.