Zeng Bizhen, Chen Kai, Li Zhuo, Zhi Xiaohan, Zhou Yumiao, Wang Yuechao, Li Tianyu, Khan Nasir Ali, Zhu Hongtao
Beijing Key Lab for Source Control Technology of Water Pollution, Beijing Forestry University, Beijing 100083, China; College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China.
Offshore Environmental Technology & Services Limited, Beijing 100020, China.
Bioresour Technol. 2025 Oct;434:132791. doi: 10.1016/j.biortech.2025.132791. Epub 2025 Jun 8.
Food wastewater (FW) is rich in biodegradable organics and holds potential for producing high-value volatile fatty acids (VFAs) via anaerobic fermentation (AF). Among influencing factors, salinity plays a key role in butyric acid production, yet the underlying mechanisms remain unclear. This study investigates salinity-driven changes in butyric acid production by analyzing organic composition, enzyme activity, and microbial community shifts. Results showed that total VFAs yield remained stable (∼13 g/L) under 0-12 g/L salinity, while 10 g/L notably enhanced butyric acid accumulation (7061.4 mg/L, 86.9 % of VFAs). Further analysis revealed that high salinity accelerated substrate degradation, particularly carbohydrates and proteins, while dynamically regulating enzyme activity involved in butyric acid synthesis. Salt stress promoted the dominance of salt-tolerant bacteria, such as Bifidobacterium, and inhibited acetic acid production pathways. These findings suggest salinity can be strategically leveraged to steer AF toward high butyric acid selectivity, offering new insights into efficient FW valorization.
食品废水（FW）富含可生物降解有机物，具有通过厌氧发酵（AF）生产高价值挥发性脂肪酸（VFA）的潜力。在影响因素中，盐度对丁酸生产起着关键作用，但其潜在机制仍不清楚。本研究通过分析有机组成、酶活性和微生物群落变化，研究盐度驱动的丁酸生产变化。结果表明，在0-12 g/L盐度下，总VFA产量保持稳定（约13 g/L），而10 g/L盐度显著提高了丁酸积累（7061.4 mg/L，占VFA的86.9%）。进一步分析表明，高盐度加速了底物降解，尤其是碳水化合物和蛋白质，同时动态调节了参与丁酸合成的酶活性。盐胁迫促进了耐盐细菌（如双歧杆菌）的优势地位，并抑制了乙酸生产途径。这些发现表明，可以战略性地利用盐度来引导厌氧发酵实现高丁酸选择性，为食品废水的高效 valorization提供了新的见解。
