Reverse osmosis membranes applied in seawater desalination plants as a source of bacteria with antifouling activity: Isolation, biochemical and molecular characterization

Abstract

Background: During lifespan of reverse osmosis systems applied in seawater desalination plants, a common phenomenon of undesirable growth and accumulation of biological material known as biofouling occurs. Microbial cells are first settlers, attaching and enclosing themselves in extracellular polymeric substances –biomass accumulation usually referred to as microfouling or biofilms, which becomes a serious issue when having a detrimental effect on materials or hampering industrial processes. Thus, control of microfouling on reverse osmosis membranes is crucial since chemical and physical treatments are usually costly and ineffective. In this context, even though microorganisms are the source of the problem, they can also provide possible solutions due to their capacity to produce secondary metabolites, being several of these competition mediators secreted compounds (i.e., bioactive molecules) produced during the stationary phase (e.g., lipases, proteases, DNases and other enzymes with alginate lyase and xanthine oxidases). Such bioactive substances can be utilized against the development of biofilms. Considering biofouled surfaces a niche for complex microbial interactions, here we have used reverse osmosis membranes and cartridge filters applied in a seawater desalination plant as a source for the isolation of bacteria with anti-fouling potential, among other biotechnological applications. Results: We obtained 27 bacterial isolates able to secrete exoenzymes displaying a wide array of bioactivity such as lipases, alginases, and glucosidases, among others. Additionally, we showed two main candidates able to inhibit the growth of common microbial colonizers of ROM and cartridge filter. Conclusions: These results highlight the potential biotechnological application of bioactive molecules against biofouling formation.How to cite: Vera-Villalobos H, Cortes-Martinez A, Gonzalez-Gutierrez Á, et al. Reverse osmosis membranes applied in seawater desalination plants as a source of bacteria with antifouling activity: Isolation, biochemical and molecular characterization. Electron J Biotechnol 2023;66. https://doi.org/10.1016/j.ejbt.2023.09.003.

Keywords

• Antibacterial supernatant
• Antifouling
• Bioactive molecules
• Biofilms
• Biofouling
• Exoenzimatic activity