In this study, the alkaline fermentation of combined lipid-rich waste (LRW) was explored to produce volatile fatty acids (VFAs). By introducing sulfate as an external electron acceptor, the long-chain fatty acid (LCFA) metabolic pathway was enhanced, achieving a VFA yield of 671.1 ± 21.9 mg COD/g VSS—an increase of 4.7 times compared to the control—under conditions of high lipid content (10 g/L). Significant conversion of LCFAs, such as oleic and linolenic acids, was achieved via the β-oxidation pathway, which also led to a synergistic enhancement of the fermentation of non-lipidic organic matter. Key functional genes from five LCFA metabolic modules were identified, revealing diverse electron transport routes, including non-syntrophic and syntrophic LCFA oxidation mediated by differentiated microbial function groups. Genome-centric metagenomics analysis further identified microbial functional groups responsible for the reconstructed pathways, offering new insights into optimizing LRW recycling and VFA production in anaerobic fermentation systems.

中文翻译：

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解锁新的电子传输途径：深入了解富含脂质的废物价值化中增强的长链脂肪酸转化率


在本研究中，探索了富脂混合废物 （LRW） 的碱性发酵以产生挥发性脂肪酸 （VFA）。通过引入硫酸盐作为外部电子受体，长链脂肪酸 （LCFA） 代谢途径得到增强，在高脂质含量 （10 g/L） 的条件下，VFA 产量达到 671.1 ± 21.9 mg COD/g VSS，比对照增加了 4.7 倍。LCFAs（如油酸和亚麻酸）的显著转化是通过β氧化途径实现的，这也导致了非脂质有机物发酵的协同增强。鉴定了来自 5 个 LCFA 代谢模块的关键功能基因，揭示了不同的电子传递途径，包括由分化微生物功能组介导的非共养和共养 LCFA 氧化。以基因组为中心的宏基因组学分析进一步确定了负责重建途径的微生物功能组，为优化厌氧发酵系统中的 LRW 回收和 VFA 生产提供了新的见解。