Antimicrobial Activity Assay of Liposomal Lipopolysaccharide Extracted from Escherichia coli

Escherichia coli (E. coli) is a bacterial bacillus known to be negative for the gram dye, and it is part of the normal flora inside the human body. The current study aimed to investigate the possibility of using lipopolysaccharides (LPS) as an antimicrobial agent. A total of 30 isolates of E. coli were collected from 100 specimens of urine isolated from patients with recurrent urinary tract infections (UTIs) referring to Al-Sadr Teaching Hospital. The samples were cultured on identification media; thereafter, they were diagnosed according to the phenotypic form, biochemical tests, and finally by VITK-2. The results of the prevalence of E. coli isolates illustrated that from 30 isolates of E. coli which were collected from 100 urine specimens, 14 (46.6%), 6 (20%), and 10 (33.3%) cases belonged to the urinary tract infections, kidney stones, and urinary catheter samples, respectively. The isolates displayed multiple drug resistance (MDR) to most of the antibiotics used in the study. Therefore, the lipopolysaccharide extracted from E. coli was used as an antimicrobial agent. The recorded data obtained from the polymerase chain reaction (PCR) for WaaA, WaaC, wamB, and wabG genes demonstrated that the isolates possessed biosynthesis genes for LPS. The results indicated that LPS at concentrations of 150, 250, and 500 μg/ml has as an anti-growth agent for Klebsiella pneumonia, Proteus mirabilis, Salmonella typhi, Pseudomonas aeruginosa, Bacillus subtilis, Staph aureus, and candida albicans. The highest inhibitory effect was observed on K. pneumonia, P. mirabilis, S. typhi, B. subtilis, and C. albicans, as compared to the control antimicrobials agents (Amoxicillin, Nystatin). The LPS loaded on liposome nanoparticles can open new horizons in medicine by its inclusion in the manufacture of broad-spectrum antibiotics.