Abstract：
Anaerobic fermentation is often inhibited under high salinity conditions. This study discovered a strong, positive association between N-butyryl-l-homoserine lactone (C4-HSL)-mediated quorum sensing (QS) and the production of volatile fatty acids (VFAs) under saline conditions. N-acyl-homoserine lactones were identified during acidogenic fermentation for VFA production. Only C4-HSL was detected at all salt concentrations, and a maximum C4-HSL concentration of 0.49 μg/L was observed at a salt concentration of 15 g/L. C4-HSL secretion was closely related to salinity, and a strong correlation was observed between C4-HSL and VFAs (p < 0.01), especially butyrate. Further experiments with C4-HSL addition indicated that exogenous C4-HSL promoted substrate hydrolysis and increased butyrate production by 1.5 times at 15 g/L NaCl. Microbial community analysis indicated that unclassified_f__Enterobacteriaceae and Clostridium_sensu_stricto_1, associated with QS genes and butyrate production, were positively associated with C4-HSL. This study demonstrates the positive effect of C4-HSL-mediated QS on acidogenic fermentation.
摘要：
厌氧发酵通常在高盐度条件下受到抑制。这项研究发现了一个强大的，在盐水条件下，N-丁酰基-1-高丝氨酸内酯（C4-HSL）介导的群体感应（QS）与挥发性脂肪酸（VFA）的产生之间呈正相关。在产酸发酵过程中鉴定了N-酰基高丝氨酸内酯以生产VFA。在所有盐浓度下仅检测到C4-HSL，在15g/L的盐浓度下观察到最大C4-HSL浓度为0.49μg/LC4-HSL分泌与盐度密切相关，C4-HSL和VFAs之间有很强的相关性（p<0.01），尤其是丁酸盐.添加C4-HSL的进一步实验表明，外源C4-HSL可促进底物水解，并在15g/LNaCl下将丁酸酯的产量提高1.5倍。微生物群落分析表明，未分类的_f__肠杆菌科和梭菌_sensu_stricto_1，与QS基因和丁酸盐的产生有关，与C4-HSL呈正相关。这项研究证明了C4-HSL介导的QS对产酸发酵的积极作用。
