Microbial diversity in biofilms from reverse osmosis membranes: A short review

Abstract

Biofilm occurrence in reverse osmosis (RO) membranes constitutes a key problem in water plants, leading to a loss of performance and a decrease in treatment efficiency. Knowledge on the microbial community composition and the links to operational conditions is therefore crucial to understand biofilm formation and develop proper biofouling management strategies. The advent of molecular methodologies in the last years has evidenced the failure of culture-dependent techniques to assess the great level of diversity present in RO membranes. More recently, the application of –omics has unveiled a new horizon to study microbial diversity and function in wastewater treatment. This manuscript focuses on the latest discoveries in prokaryotic diversity in RO membranes, highlighting the importance of operating conditions and cleaning strategies in community structure. The current knowledge of biofilm dynamics in these systems is also reviewed. However, despite the enormous possibilities that metagenomics and metatranscriptomics can offer, studies using these methodologies in RO membranes are still scarce, and further efforts to uncover a core microbial composition and expression patterns of relevant genes are still needed.