解硫胺素芽孢杆菌JXN-1产己酸发酵培养基优化

Optimization of the Fermentation Medium of Aneurinibacillus JXN-1 for Caproic Acid Production

摘要:

【目的】提高解硫胺素芽孢杆菌JXN-1的己酸产量。【方法】采用Plackett-Burman试验从8种培养基成分中筛选出影响己酸产量的显著因素；通过最陡爬坡试验确定显著因素的最佳水平范围；利用Box-Behnken试验建立二次多项式回归模型，并对显著因素的交互作用进行分析，预测最优培养基组合。【结果】Plackett-Burman试验筛选出乙酸钠质量浓度、四氢叶酸钙质量浓度和乙醇体积分数为显著影响因素。Box-Behnken试验建立的回归模型极显著（P<0.01），模型预测的最佳培养基组合为：蔗糖质量浓度7.50 g/L、酵母膏质量浓度1.00 g/L、七水硫酸镁质量浓度0.20 g/L、乙酸钠质量浓度4.08 g/L、硫酸铵质量浓度0.45 g/L、四氢叶酸钙质量浓度2.88 mg/L、磷酸氢二钾质量浓度0.60 g/L、乙醇体积分数2.53%，该条件下发酵液中实测己酸质量浓度与模型预测值高度吻合，较优化前提高了212.47%。【结论】作者成功优化了解硫胺素芽孢杆菌JXN-1产己酸的发酵培养基。优化后的培养基能显著提升己酸产量，为该菌株在白酒酿造中的实际应用提供了理论依据和技术参考。

Abstract:

[Objective]This study aims to increase the caproic acid yield of Aneurinibacillus JXN-1.[Method]First, a Plackett-Burman design was employed to screen the significant factors affecting caproic acid yield from eight medium components. Subsequently, the path of steepest ascent method was used to determine the optimal concentration ranges of these significant factors. Finally, a Box-Behnken design was utilized to establish a quadratic polynomial regression model, and the interactions among the significant factors were analyzed to predict the optimal medium composition.[Result]The Plackett-Burman design identified the mass concentrations of sodium acetate and calcium folinate and the volume fraction of ethanol as significant influencing factors. The regression model established by the Box-Behnken design was highly significant (P<0.01). The predicted optimal medium composition was as follows: sucrose mass concentration of 7.50 g/L, yeast extract mass concentration of 1.00 g/L, magnesium sulfate heptahydrate mass concentration of 0.20 g/L, sodium acetate mass concentration of 4.08 g/L, ammonium sulfate mass concentration of 0.45 g/L, calcium folinate mass concentration of 2.88 mg/L, dipotassium hydrogen phosphate mass concentration of 0.60 g/L, and ethanol volume fraction of 2.53%. Under these conditions, the actual caproic acid yield was in high agreement with the model predicted value, representing an increase of 212.47% compared with the pre-optimization level.[Conclusion]This study successfully optimizes the fermentation medium for caproic acid production by Aneurinibacillus JXN-1. The optimized medium significantly enhances the caproic acid yield, providing a theoretical basis and technical reference for the practical application of this strain in Baijiu brewing.