Abstract Fermentation conditions affect pectinase production. Among these conditions, fermentation period is one of the important parameters to be optimized for saving the process costs. However, information regarding whether metabolic regulation plays a role is not available. Here, a Bacillus licheniformis strain DY2 was incubated in submerged fermentation for pectinase production for 48 h. The pectinase activity was assayed every 4 h from 8th h of fermentation. The pectinase activity was low at 8 h, middle at 28 h, and peak at 44 h. Consistently, metabolomics analysis showed that the metabolic shift is related to the fermentation period. The metabolomes exhibited almost of differential metabolites in the enriched metabolic pathways, which were decreased at 28 h and 44 h compared to 8 h in a time-dependent manner. Furthermore, reduced palmitic acid and stearic acid in a time-dependent manner were identified as crucial biomarkers at 48 h. These findings in our work reveal that the reduced fatty acid biosynthesis is required for pectinase yield, which was further demonstrated by addition of inhibitors furfural and triclosan to inhibit pyruvate dehydrogenase and fatty acid biosynthesis, respectively. Our work reveals a potential possibility to elevate pectinase yield through metabolomics modulation.

中文翻译：

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发酵时间依赖性果胶酶活性与地衣芽孢杆菌 DY2 的代谢组学变异相关

摘要 发酵条件影响果胶酶的产生。在这些条件中，发酵周期是为节省工艺成本而需要优化的重要参数之一。然而，关于代谢调节是否起作用的信息尚不可用。在这里，地衣芽孢杆菌菌株 DY2 在深层发酵中培养以生产果胶酶 48 小时。从发酵第 8 小时起每 4 小时检测一次果胶酶活性。果胶酶活性在 8 小时低，28 小时中等，44 小时达到峰值。代谢组学分析一致表明，代谢转变与发酵期有关。代谢组在富集的代谢途径中几乎表现出差异代谢物，与 8 小时相比，这些代谢物在 28 小时和 44 小时以时间依赖性方式减少。此外，以时间依赖性方式还原的棕榈酸和硬脂酸被鉴定为 48 小时时的关键生物标志物。我们工作中的这些发现表明，果胶酶产量需要减少脂肪酸生物合成，这通过添加抑制剂糠醛和三氯生分别抑制丙酮酸脱氢酶和脂肪酸生物合成进一步证明。我们的工作揭示了通过代谢组学调节提高果胶酶产量的潜在可能性。