Mitigation of biofouling in forward osmosis process by bacteria-oriented quorum quenching molecules

Abstract

In this study, the intervention of bacterial communication or quorum quenching (QQ) technique has been investigated to mitigate biofouling in forward osmosis (FO) membrane processes. The 10 mg-C/L lysate of QQ enzyme-producing Rhodococcus sp. BH4 successfully degraded 79% of the bacterial signal molecule (N-acyl homoserine lactone, AHL). In a continuous lab-scale FO experiment using Pseudomonas aeruginosa PAO1 as a model bio-foulant, flux recovery after physical cleaning was higher in the presence of 10 mg/L of Rhodococcus lysate. The retardation of biofouling in the presence of Rhodococcus lysate was largely due to the reduced amount of bio-volume and extracellular polymeric substances (EPS), which were reduced by 68% and 75% compared with the control. In conclusion, the application of bacteria-oriented QQ molecules could be the potential solution not only to mitigate biofouling but also to meet the economic demands.