Aims: Due to its rapid development of resistance against most conventional antibiotics, there is an urgent need to develop new antimicrobial agents and strategies to overcome the challenges in combating multidrug-resistant Pseudomonas aeruginosa infections. This study aimed to determine the antipseudomonal potency of bacteriocin produced by Pediococcus pentosaceus TU2 when combined with conventional antibiotics. Methodology and results: The checkerboard method and time-kill assay were conducted to investigate the antagonism interaction and kinetics of the bacteriocin TU2 and selected antibiotics against Pseudomonas aeruginosa ATCC10145. The scanning electron microscope (SEM) was used to observe the cell surface morphological changes of the treated P. aeruginosa ATCC10145. The combination of bacteriocin TU2 with ciprofloxacin and tetracycline resulted in a 4-fold reduction in minimum inhibitory concentration (MIC) and a fractional inhibitory concentration index (ΣFICI) of 0.5, indicating a synergistic interaction against P. aeruginosa ATCC10145. Similarly, the time-kill assay showed that the combination of bacteriocins TU2 respectively with chloramphenicol and tetracycline exerted enhanced bactericidal effect at 8 h and 10 h of treatments compared to treatment with antimicrobial agents alone. Results from SEM suggested that bacteriocin TU2 might cause pore formation on cells and thus enhanced the membrane permeability of antibiotics and intensified the membrane leakage that led to cell death of P. aeruginosa ATCC10145. Conclusion, significance and impact of study The combined antagonistic effect of bacteriocin TU2 and antibiotics could be a promising strategy in combating P. aeruginosa infections and may be applied in therapeutic industries.
Tuberculosis, Multidrug-Resistant ; Pseudomonas aeruginosa ; Pediococcus pentosaceus