Quorum sensing regulation methods and their effects on biofilm in biological waste treatment systems: A review

Quorum sensing (QS) plays an important role in microbial aggregation control. Recently, the optimization of biological waste treatment systems by QS regulation gained an increasing attention. The effects of QS regulation on treatment performances and biofilm were frequently investigated. To understand the state of art of QS regulation, this review summarizes the methods of QS enhancement and QS inhibition in biological waste treatment systems. Typical QS enhancement methods include adding exogenous QS molecules, adding QS accelerants and cultivating QS bacteria, while typical QS inhibition methods include additions of quorum quenching (QQ) bacteria, QS-degrading enzymes, QS-degrading oxidants, and QS inhibitors. The specific improvements after applying these QS regulation methods in different treatment systems are concluded. In addition, the effects of QS regulation methods on biofilm in biological waste treatment systems are reviewed in terms of biofilm formation, extracellular polymeric substances production, microbial viability, and microbial community. In the end, the knowledge gaps in current researches are analyzed, and the requirements for future study are suggested. (C) The Author(s) 2021. This article is published with open access at link.springer.com and journal.hep.com.cn

Automated summary

Quorum sensing (QS) plays a crucial role in controlling microbial aggregation, and the optimization of biological waste treatment systems by QS regulation has gained significant attention. This review summarizes the methods of enhancing and inhibiting QS in biological waste treatment systems and concludes the specific improvements achieved in different treatment systems. Moreover, it reviews the effects of QS regulation methods on biofilm and analyzes the knowledge gaps in current research, providing suggestions for future studies.