Prevalence and genetic diversity of Enterobacter sakazakii in ingredients of infant foods

Int J Food Microbiol. 2008 Feb 29;122(1-2):196-203. doi: 10.1016/j.ijfoodmicro.2007.11.072. Epub 2007 Dec 4.

Abstract

Various food samples in Korea were examined for the presence of Enterobacter sakazakii. Dried shrimp had the highest contamination rate among the examined dried fish products. E. sakazakii isolates were confirmed using an API 20E kit and a polymerase chain reaction (PCR) targeting the rDNA operons. The isolates were subtyped by pulsed-field gel electrophoresis (PFGE) using XbaI to elucidate the genetic diversity of the organisms. Ten pulsotypes were identified using PFGE and 22 types were identified from the random amplified polymorphism DNA (RAPD) assay. An antibiotic resistance test was performed by disk diffusion assay using eight antibiotics: nalidixic acid, ciprofloxacin, chloramphenicol, ampicillin, tetracycline, gentamicin, kanamycin, and cephalothin. Most of the E. sakazakii isolates were resistant to ampicillin or cephalothin but susceptible to the other antibiotics. The analysis of E. sakazakii isolates using PFGE, RAPD, and the antibiotic resistance test identified 18 composite types from 113 isolates, suggesting diverse sources of contamination.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Anti-Bacterial Agents / pharmacology*
  • Colony Count, Microbial
  • Consumer Product Safety
  • Cronobacter sakazakii / drug effects
  • Cronobacter sakazakii / genetics*
  • Cronobacter sakazakii / isolation & purification
  • DNA, Bacterial / analysis
  • Dose-Response Relationship, Drug
  • Drug Resistance, Bacterial
  • Electrophoresis, Gel, Pulsed-Field
  • Food Contamination / analysis*
  • Genetic Variation*
  • Humans
  • Infant
  • Infant Food / microbiology*
  • Microbial Sensitivity Tests
  • Prevalence
  • Random Amplified Polymorphic DNA Technique
  • Seafood / microbiology
  • Shellfish / microbiology

Substances

  • Anti-Bacterial Agents
  • DNA, Bacterial