In this paper, the activities of signal molecule AI-2 in the sole fermentation of and co-fermentation of and were investigated. Co-fermentation of and was found to reduce to secrete AI-2. Three AI-2 quorum sensing inhibitors (DMHF (2,5-Dimethyl-4-hydroxy-3-(2H)-furanone), D-Rib (-Ribose), and D-Gal (-Galactosamine)) were added to the co-fermentation system to further interrupt the growth of . It was found that 0.2 g/L DMHF or 18.0 g/L D-Gal could mainly decrease the activity of AI-2 by 38 % and 36 %, respectively, and significantly inhibit the biofilm formation of . Moreover, the ethanol concentrations of the co-fermentation trials added with 0.2 g/L DMHF or 18.0 g/L D-Gal were 14 % and 103 % higher than that of the control, respectively, within 30 h of fermentation. This study provides basic data for the novel prevention of contamination in bioethanol production via quorum sensing control, which is meaningful for the environmental protection and the sustainable development of bioethanol industry.

中文翻译：

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AI-2 群体感应抑制剂对减轻生物乙醇生产中细菌污染的影响

本文研究了信号分子AI-2在单独发酵和共发酵中的活性。发现和的共发酵减少了AI-2的分泌。将三种 AI-2 群体感应抑制剂（DMHF（2,5-二甲基-4-羟基-3-(2H)-呋喃酮）、D-Rib（-核糖）和 D-Gal（-半乳糖胺））添加到共发酵系统进一步中断 的生长。结果发现，0.2 g/L DMHF或18.0 g/L D-Gal主要可分别降低AI-2活性38%和36%，并显着抑制生物膜形成。此外，添加0.2 g/L DMHF或18.0 g/L D-Gal的共发酵试验在发酵30小时内乙醇浓度分别比对照高14%和103%。该研究为通过群体感应控制新型预防生物乙醇生产中的污染提供了基础数据，对于环境保护和生物乙醇产业的可持续发展具有重要意义。