Bacterial adhesion inhibition on water treatment membrane by a modified HHC-36 antimicrobial peptide

Abstract

Antimicrobial peptides (AMPs) are now used instead of conventional antimicrobial substances because they do not induce resistance in microbial cells. The first goal of this study was to investigate how various dissolution solvents, such as dimethyl sulfoxide (DMSO), phosphate buffered saline (PBS) and autoclaved deionized (DI) water, affect the antimicrobial potency of an AMP (HHC-36) modified with L -propargylglycine (PraAMP) against Pseudomonas aeruginosa PAO1, Escherichia coli, and Bacillus sp. The potential application of HHC-36 AMP as a biofouling control agent on water treatment membranes was then investigated using a membrane fouling bacterium as a model. At concentrations greater than 0.5 mg/mL, the AMP demonstrated significant antibacterial efficacy against all the bacteria species. However, the initial dissolution of the HHC-36 AMP in DMSO had a significant impact on its antibacterial effects. DMSO alone (≥ 12.4% vol/vol) exhibited a significant bacterial growth inhibition. This finding is noteworthy because DMSO is commonly used as a solvent for antimicrobial agents that are insoluble in water. Overall, by disrupting bacterial cell membranes, the HHC-36 AMP was able to inactivate bacterial cells on water treatment membrane. This study recapitulates the feasible use of environmentally friendly AMP as antibiofouling agents in water treatment processes.