Quorum quenching bacteria can be used to inhibit the biofouling of reverse osmosis membranes. (1st April 2017)

• Record Type: Journal Article
• Authors: Oh, Hyun-Suk; Tan, Chuan Hao; Low, Jiun Hui; Rzechowicz, Miles; Siddiqui, Muhammad Faisal; Winters, Harvey; Kjelleberg, Staffan; Fane, Anthony G.; Rice, Scott A.
• Is Part Of: Water research. Volume 112(2017)
• Page Start: 29
• Page End: 37
• Publication Date: 2017-04-01
• Subjects: Reverse osmosis -- Biofouling -- Quorum sensing -- Quorum quenching bacteria -- N-acylhomoserine lactone -- Biofilms; Water -- Pollution -- Research -- Periodicals; 363.7394
• DOI: 10.1016/j.watres.2017.01.028
• Languages: English
• ISSNs: 0043-1354

Abstract

Abstract: Over the last few decades, significant efforts have concentrated on mitigating biofouling in reverse osmosis (RO) systems, with a focus on non-toxic and sustainable strategies. Here, we explored the potential of applying quorum quenching (QQ) bacteria to control biofouling in a laboratory-scale RO system. For these experiments, Pantoea stewartii was used as a model biofilm forming organism because it was previously shown to be a relevant wastewater isolate that also forms biofilms in a quorum sensing (QS) dependent fashion. A recombinant Escherichia coli strain, which can produce a QQ enzyme, was first tested in batch biofilm assays and significantly reduced biofilm formation by P. stewartii . Subsequently, RO membranes were fouled with P. stewartii and the QQ bacterium was introduced into the RO system using two different strategies, direct injection and immobilization within a cartridge microfilter. When the QQ bacterial cells were directly injected into the system, N- acylhomoserine lactone signals were degraded, resulting in the reduction of biofouling. Similarly, the QQ bacteria controlled biofouling when immobilized within a microfilter placed downstream of the RO module to remove QS signals circulating in the system. These results demonstrate the proof-of-principle that QQ can be applied to control biofouling of RO membranes and may be applicable for use in full-scale plants. Graphical abstract: Highlights: A recombinant Quorum Quenching (QQ) bacterium controlled biofilm formation. Direct injection of QQ bacteria in a lab-scale RO system mitigated biofouling. QQ bacteria controlled biofouling when immobilized within a microfilter cartridge.