Evaluation of Lactobacillus brevis supernatant onPseudomonas aeruginosa biofilm formation

Background and Aim : Pseudomonas aeruginosa is one of the most causes of healthcareassociatedinfections, including urinary tract infections, nosocomial pneumonia, bloodstreaminfections, and skin infections. Unfortunately, Pseudomonas aeruginosa shows resistance to avariety of antibiotics. One of the most serious consequences of microbial biofilms is that thebacteria can tolerate and survive at high concentrations of antibiotics. According to this issue inour project, we evaluated the Lactobacillus brevis supernatant on Pseudomonas aeruginosa biofilmformationMethods : In this assessment, MIC and Disk Diffusion techniques were used to evaluate the effectof Lactobacillus brevis on Pseudomonas aeruginosa strains. In this regard, Bacteria-freesupernatant was obtained by centrifugation at ۱۲۰۰۰ rpm for ۲۰ min. To ensure the cell-free statusof bacterial cells, supernatants were passed through a ۰.۴ μm pore size filter. The effect ofantibacterial activity of the supernatant of probiotic was evaluated after ۲۴h at ۳۷°C.Results : The highest resistance was to Ciprofloxacin, Imipenem, Amikacin, Gentamicin,Tobramycin, and Cefotaxime. Lactobacillus brevis supernatant was used for MIC assay. Theresults show that MIC for all isolates was ۵۰ μl against Pseudomonas aeruginosa.Conclusion : Briefly, probiotics could affect biofilm formation of Pseudomonas aeruginosa andlikely this issue is due to the effect on host cells through regulating the transcription of itsvirulence-associated factors. Probiotic bacteria have numerous effects on medical aspects. One ofthem is related to utilize for inhibition of biofilm. These days, due to the lack of proper antibioticsfor several infections, probiotics could be highly useful.

کلیدواژه ها:

MIC ، Lactobacillus brevis ، Pseudomonas aeruginosa