ISOLATION, MOLECULAR CHARACTERIZATIONAND ANTIBACTERIAL SUSCEPTIBILITY PATTERNSOF Escherichia coli FROM FRUIT JUICES

Abstract

This study was undertaken to determine the molecular profile and the antibiotic susceptibility patterns of Escherichia coli isolated from fruit juices. A total number of one hundred and five (105) fruit juice samples were analyzed out of which E. coli were detected in 11% of the samples. Each E. coli strain isolated was characterized using molecular characterization by PCR method to determine the presence of virulence genes in each strain. DNA was extracted from twelve (12) E. coli strains from which they were further subjected to uniplex PCR amplification to detect the presence of virulence genes using five (5) oligonucleotide primers found in E. coli strains causing infections and out of the twelve (12) E. coli strains analyzed, 4 (33.3%) isolates carried stx1 gene, 7 (58.3%) possessed stx2 gene whereas Intimin (eae), haemolysin (hly) and chromosomal flagellin (flich) virulence genes were detected in 3 (25.0%), 5 (41.7%) and 6 (50.0%) of the isolates respectively. Antibacterial susceptibility profiles of the isolates to eight (8) antibacterial agents; cotrimoxazole (cot), 25μg; chloramphenicol (chl), 10μg; tetracycline (tet), 10 μg; streptomycin (str), 10 μg; augmentin (aug), 30 μg; gentamicin (gen), 10 μg; erythromycin (ery), 5 μg; cloxacillin (cxc), 5 μg were investigated by disk diffusion method. The antibacterial susceptibility patterns of E. coli were in this order: (gentamicin – 8.33%), (streptomycin and gentamicin – 50.0%), (chloramphenicol, streptomycin and gentamicin – 25.0%), (cotrimoxazole, chloramphenicol, streptomycin and gentamicin – 8.33%) and (cotrimoxazole, chloramphenicol, tetracycline, streptomycin, gentamicin and erythromycin – 8.33%). All the twelve (12) E. coli strains isolated from fruit juice samples showed five antibacterial susceptibility patterns, ranging from one to six. Also all the twelve (12) E. coli strains showed five antibacterial resistance patterns, out of which all were multiple antibacterial resistant with the number of antibacterial agents ranging from three to seven. In conclusion, there was a clear indication of the presence of E. coli in fruit juice samples analyzed, the presence of virulence genes in the E. coli strains and high resistance to antibacterial agents were observed in the E. coli isolates.