Vitamin B₁₂ (VB₁₂) is an indispensable cofactor of metabolic enzymes and has been widely used in the food and pharmaceutical industries. In this study, the effects of medium composition on VB₁₂ production by Propionibacterium freudenreichii were evaluated and optimized based on statistical experiments. The results showed that glucose, yeast extract, KH₂PO₄, and glycine have significant effects on VB₁₂ production. The final titer of VB₁₂ reached 8.32 ± 0.02 mg/L, representing a 120% increase over the non-optimized culture medium. We employed a metabolomics approach to analyze the differences of metabolite concentrations in P. freudenreichii cells cultivated in the original medium and optimized fermentation medium. Using multivariate data analysis, we identified a range of correlated metabolites, illustrating how metabolomics can be used to explain VB₁₂ production changes by corresponding differences in the overall cellular metabolism. The concentrations of many metabolic intermediates of glycolysis, the Wood–Werkman cycle, the TCA cycle, and amino acid metabolism were increased, which contributed to the synthesis of propionic acid and VB₁₂ due to an improved supply of energy and precursors.

中文翻译：

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维生素 B12 生产者费氏丙酸杆菌的代谢谱分析

维生素B ₁₂ (VB ₁₂ )是代谢酶不可缺少的辅助因子，已广泛应用于食品和制药行业。在本研究中，基于统计实验评估和优化培养基组成对费氏丙酸杆菌产生VB _{12的影响。}结果表明，葡萄糖、酵母提取物、KH ₂ PO ₄和甘氨酸对VB ₁₂的产生有显着影响。_{VB 12}的最终滴度达到 8.32 ± 0.02 mg/L，比未优化的培养基增加了 120%。我们采用代谢组学方法分析代谢物浓度的差异磷。在原始培养基和优化的发酵培养基中培养的弗洛伊登氏菌细胞。使用多变量数据分析，我们确定了一系列相关代谢物，说明代谢组学如何通过整体细胞代谢的相应差异来解释 VB _{12产生的变化。}糖酵解、Wood-Werkman 循环、TCA 循环和氨基酸代谢的许多代谢中间体的浓度增加，由于能量和前体供应的改善，这有助于丙酸和 VB _{12的合成。}