由现场乳酸预发酵驱动的中国白菜废弃物生产的六酸:pH值的影响
Zhengang Chen1, Liu Huang1, Xiaofeng Ji1
1School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo, 255000, China.
Applied biochemistry and biotechnology
|July 16, 2025
概括
优化pH值是有效生产六酸的关键,通过链条延长,使用来自中国白菜废物的乳酸. 值为5.5的pH值通过促进有益细菌来最大限度地提高六酸的产量.
科学领域:
- 生物技术是生物技术.
- 微生物学 微生物学
- 可持续化学 可持续化学
背景情况:
- 链延长 (CE) 将乳酸转化为六酸,这是一个有价值的化学物质.
- 在CE工艺中,pH显著影响代谢途径和产品产量.
- 中国卷心菜废弃物 (CCW) 的预发酵可以产生高度的乳酸.
研究的目的:
- 调查pH对乳酸代谢和CE期间的六酸生产的影响.
- 为了优化CE条件,最大限度地提高CCW衍生乳酸的六酸产量.
主要方法:
- CCW的预发酵以产生乳酸.
- 在不同的pH值 (5.5和6.0) 和没有pH控制的情况下进行受控的CE实验.
- 微生物社区分析以确定涉及不同pH条件的关键细菌.
主要成果:
- 一个pH值为5.5,具有特定的微生物群落 (乳酸菌,Caproiciproducens,Acinetobacter),产生了最高的六酸度 (5.01gCOD/L).
- 在pH值6.0时,产生酸的细菌 (Blautia,Succiniclasticum) 占主导地位,将乳酸转化为酸,并降低了六酸的选择性.
- 由于最初的低pH条件,不受控制的pH导致乙酸成为主要产品.
结论:
- pH 5.5是最大限度地通过CCW的乳酸CE最大限度地提高六酸的产量.
- 微生物群落的组成对pH极为敏感,决定了代谢流向六酸或酸.
- 控制pH对于指导碳流和在CE过程中实现高选择性至关重要.
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