الفهرس | Only 14 pages are availabe for public view |
Abstract ”The presence of Enterobacteria in food in large numbers indicates fecal contamination. This study was carried out to screen different Ready-to-eat foods (RTEs) for the presence of different foodborne pathogens of Enterobacteriaceae family in Damietta market, identification of isolates and characterization of their antimicrobial susceptibility. Moreover, phenotypic and molecular detection of some virulence factors were performed. Enterobacteriaceae isolates were detected among 34/40 (85%) of the examined RTEs. They were distributed by different percentages with different mean counts among these collected samples. A total of 139 isolates were identified. Seven genera comprising 16 species. were detected in which the most frequent genus was Klebsiella followed by Enterobacter. Other members: Citrobacter spp., Proteus spp., Providencia spp., and E. coli spp., were also identified. In addition, all of the confirmed E. coli and K. pneumoniae isolates were serologically identified. Antimicrobial susceptibility of the isolates to 12 antimicrobial agents was determined by disc diffusion method. Most of the tested isolates showed high resistance percentages to cefepime and ampicillin. Imipenem, ciprofloxacin, amikacin, gentamicin, and cefotaxime were the most effective antimicrobials. Enterobacteriaceae isolates were phenotypically investigated for possessing some virulence factors (biofilm, hemolysin, haemagglutination, serum resistance and hypermucoviscosity test (K. pneumoniae isolates only). Eighteen different virulence encoding genes were screened by PCR for Enterobacteriaceae isolates.Various virulence patterns were detected within the species. Molecular typing was carried out for K. pneumoniae, E. coli and Proteus spp. using (GTG)5-PCR, ERIC, RAPD, ISSR and BOX typing primers ” |