The effect of Lactobacillus acidophilus as a probiotic against Pseudomonas aeruginosa growth and biofilm formation

Abstract

Abstract The emergence of antibiotic-resistant microorganisms as Pseudomonas aeruginosa has pushed efforts to find safe alternatives of antibiotics as probiotics which include Lactobacilli strains with a large antibacterial and anti- biofilm effects against different pathogenic strains. Antibiotic susceptibility test and antibiogram were done for 35 isolated P. aeruginosa strains from ICU patients followed by assessment of Lactobacillus acidophilus as antibacterial and antibiofilm formation/removal against them by using different methods. The results showed that among the 35 P. aeruginosa strains, 1 (2.8%), 2 (5.7%), and 32 (91.4%) were PDR, XDR, and MDR, respectively. The effective antibiotics against them was Aztreonam. L.acidophilus with ATCC 4356, showed powerful inhibition and anti-biofilm effects against all isolated P. aeruginosa strains. It significantly inhibits biofilms by 68.52% with mean optical density reading 0.72 ± 0.44 and removes already formed biofilms by 43.8 % with mean optical density reading 1.28 ± 0.65. It was concluded that L.acidophilus can be used in bio-control of different antibiotic resistant biofilm producing P.aeruginosa strains.