在废弃活性污泥发酵中的pH依赖的中链脂肪酸合成:代谢途径调节
Yun Wang1, Shu-Lin Wu2, Wei Wei3
1State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, PR China.
Journal of environmental management
|December 18, 2024
概括
中性pH优化了使用链延长 (CE) 来从废弃活性污泥 (WAS) 中生产中链脂肪酸 (MCFA). 这种pH值增强了微生物活动和代谢途径,这对于有效的MCFA合成和WAS降解至关重要.
科学领域:
- 环境科学 环境科学
- 生物技术是生物技术.
- 微生物学 微生物学
背景情况:
- 废弃活性污泥 (WAS) 通过链延长 (CE) 转化为中链脂肪酸 (MCFA) 是一种可持续的方法.
- 对于pH对CE转换为WAS的效率的影响仍然不够理解.
研究的目的:
- 使用CE技术研究不同pH值 (酸性,中性,性) 对WAS降解和MCFA生产的影响.
- 阐明在不同pH条件下控制CE的微生物和代谢机制.
主要方法:
- 进行了半连续流体实验,以评估在pH值5,7和10时的WAS降解和MCFA产量.
- 使用元基因组和元转录组分析来了解与CE相关的微生物社区结构和基因表达.
主要成果:
- 性pH (10) 最大化了WAS降解,但不支持CE用于MCFA生产.
- 酸性 (pH5) 和中性 (pH7) 条件都使CE成为可能,中性pH产生了优异的结果.
- 与酸性pH相比,中性pH (7) 导致更高的MCFA产量 (8.9gCOD/L),选择性 (51.2%) 和WAS降解 (25.4%).
- 代谢分析显示,反向β-氧化循环是首要的CE途径.
- 中性pH偏好了氨基酸和丁酸盐代谢,增强了CE相关的微生物活动,并丰富了Clostridium_kluyveri和Sporanaerobacter_acetigenes等关键细菌.
结论:
- 中性pH值是从WAS通过CE生产MCFA的最佳条件,平衡了污泥降解与高效的脂肪酸合成.
- 微生物群体的组成,酶活性和代谢途径受到pH的显著影响,决定了CE过程的性能.
- 了解pH依赖的微生物生态对于优化可持续生物转化过程至关重要.
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