Multiple Confirmation and RAPD-genotyping of Enterobacter sakazakii Isolated from Sunsik

선식에서 분리한 Enterobacter sakazakii의 복합동정 및 RAPD를 이용한 genotyping

  • Choi, Jae-Won (Food Safety Research Division, Korea Food Research Institute) ;
  • Kim, Yun-Ji (Food Safety Research Division, Korea Food Research Institute) ;
  • Lee, Jong-Kyung (Food Safety Research Division, Korea Food Research Institute) ;
  • Kim, Young-Ho (Food Safety Research Division, Korea Food Research Institute) ;
  • Kwon, Ki-Sung (Center for Food Evaluation, Korea Food and Drug Adminstration) ;
  • Hwang, In-Gyun (Center for Food Evaluation, Korea Food and Drug Adminstration) ;
  • Oh, Se-Wook (Food Safety Research Division, Korea Food Research Institute)
  • 최재원 (한국식품연구원 안전성연구단) ;
  • 김윤지 (한국식품연구원 안전성연구단) ;
  • 이종경 (한국식품연구원 안전성연구단) ;
  • 김영호 (한국식품연구원 안전성연구단) ;
  • 권기성 (식품의약품안전청 식품평가부) ;
  • 황인균 (식품의약품안전청 식품평가부) ;
  • 오세욱 (한국식품연구원 안전성연구단)
  • Published : 2008.02.28


Enterobacter sakazakii is implicated in severe forms of neonatal infections such as meningitis and sepsis. This organism has been isolated from a wide range of foods, including cheese, vegetables, grains, herbs, and spices, but its primary environment is still unknown. Generally, dried infant milk formula has been epidemiologically identified as the source of E. sakazakii. Sunsik (a powdered mixture of roasted grains and other foodstuffs) is widely consumed in Korea as a side dish or energy supplement. Sunsik is consumed without heat treatment; thus, lacking an additional opportunity to inactivate foodborne pathogens. Therefore, its microbiological safety should be guaranteed. In this study, the prevalence of E. sakazakii was monitored in 23 different sunsik component flours, using FDA recommended methods; but E. sakazakii medium (Neogen) and Chromogenic E. sakazakii medium (Oxoid) were used as the selective media. In total, presumptive E. sakazakii strains were isolated from 8 different sunsik powders. Subsequently, an API 20E test was conducted, and 15 strains from 5 different sunsik flours (sea tangle, brown rice, non-glutinous rice, cheonggukjang, dried anchovy) were confirmed as E. sakazakii. Fifteen strains were again confirmed by PCR amplification, using three different primer sets (tDNA sequence, ITS sequence, 16S rRNA sequence), and compared to ATCC strains (12868, 29004, 29544, 51329). They were once again confirmed by their enzyme production profiles using an API ZYM kit. Finally, RAPD (random amplified polymorphic DNA)-genotyping was carried out as a monitoring tool to determine the contamination route of E. sakazakii during processing.


Enterobacter sakazakii;isolation;confirmation;PCR;genotyping


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