QUORUM-SENSING DRIVEN INHIBITORS FOR MITIGATING MICROBIAL INFLUENCED CORROSION

Abstract

Microbiologically influenced corrosion (MIC) is a process in which microorganisms initiate, facilitate, and/or accelerate the corrosion reactions of metallic components. It is documented that MIC accounts for about 20 - 40 % of the total cost of corrosion. Biofilm formation on the surface of metal components plays a vital role in MIC, which leads to severe consequences in various environmental and industrial settings. Quorum sensing (QS) system is a key contributor to biofilm formation and the expression of some microbial enzymes. QS is a communication mechanism between microorganisms that involves the regulation of gene expression as a response to the microbial cell density within an environment. Both Gram-positive and Gram-negative bacteria employ it to regulate various physiological functions. QS involves production, and detection of, and responses to signalling chemicals, known as auto-inducers. QS controls specific processes important for the microbial community, such as biofilm formation, virulence factor expression, production of secondary metabolites and stress adaptation mechanisms. QS inhibitors (QSIs) has been proposed to address the biofilm related challenges in many different applications. Although QSIs have demonstrated some strength in tackling biofouling, QSI-based strategies to control microbially influenced corrosion have not been thoroughly investigated. As such, this article aims to target the QS mechanisms as a strategy for mitigating MIC on metal surfaces in engineered systems. Initial results obtained in this study confirmed QSI ability to slow the biofilm formation and increased the metal resistance to corrosion caused by Pseudomonas aeruginosa.