ABSTRACT
Bacteria can negatively affect the operation performance of a large number of industrial plants and especially processes related to water and wastewater treatment and reuse, by the formation of biofilm in the infrastructures, a process that is known as biofouling. Biofilm formation is mediated through several inter-species and intra-species signaling systems, known as quorum sensing. Quorum sensing enables bacteria to synchronize the expression of several phenotypes, among them biofilm formation, using small molecules as auto-inducers. Quorum quenching is the disruption of those signaling pathways and could be used to reduce biofilm formation. The use of quorum quenching enzymes, inhibitors, and bacteria is well studied in membrane bioreactors. In particular, the use of microorganisms, which degrade N-acyl-homoserine lactones, is an established method in membrane bioreactors (MBRs) used for wastewater treatment, and the isolation of several strains has shown very promising results. However, further research is necessary for the optimization of this process and the elucidation of the potential impact on effluent quality characteristics. Other applications of quorum quenching have been examined, such as prevention of biofilm in catheters and reduction of antibiotic resistance genes in the soil. In addition, there are several infrastructures, such as metal pipes and cooling systems, that are impacted by biofouling, which constitutes the last step before microbial induced corrosion. Quorum quenching represents a promising technique to address those effects.
