Korean Journal of Food Science and Technology (한국식품과학회지)

Korean Society of Food Science and Technology (한국식품과학회)
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16S rRNA gene-based sequencing of cucumber (Cucumis sativus L.) microbiota cultivated in South Korea

16S rRNA 유전자 염기서열 분석에 기반한 국내 재배 오이의 상재균총 분석

  • Seo, Dong Woo (Department of Food Science and Technology, Chungnam National University) ;
  • Kim, Seung Min (Division of Human Ecology, Korea National Open University) ;
  • Lee, Heoun Reoul (Department of Food Science and Technology, Chungnam National University) ;
  • Yum, Su-jin (Department of Food Science and Technology, Chungnam National University) ;
  • Jeong, Hee Gon (Department of Food Science and Technology, Chungnam National University)
  • 서동우 (충남대학교 식품공학과) ;
  • 김승민 (한국방송통신대학교 생활과학부) ;
  • 이현열 (충남대학교 식품공학과) ;
  • 염수진 (충남대학교 식품공학과) ;
  • 정희곤 (충남대학교 식품공학과)
  • Received : 2021.01.26
  • Accepted : 2021.05.10
  • Published : 2021.06.30
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Abstract

Various vegetables, including cucumbers, have a high probability of foodborne illness because they are usually eaten raw. In this study, we analyzed the 16S rRNA gene sequences of the cucumber (Cucumis sativus L.) microbiota. The diversity indices of cucumber cultivated in May were higher than in cucumber cultivated in November. At the phylum level, Proteobacteria, Firmicutes, and Actinobacteria were predominant. The classes generally comprised Gammaproteobacteria, Bacilli, Alphaproteobacteria, and Actinobacteria. At the genus level, the proportions of Aureimonas, Escherichia, and Microbacterium in samples from May were relatively high, whereas Enterococcus, Pseudomonas, and Rhizobium accounted for a higher proportion in samples from November. Moreover, it is noteworthy that potential pathogenic genera such as Acinetobacter, Aerococcus, Aureimonas, Enterobacter, Enterococcus, Escherichia, Pantoea, Pseudomonas, and Staphylococcus were detected. Although further studies on the characteristics of potential pathogens are required, our results can be used to improve the food safety of vegetables.

본 연구에서는 16S rRNA 염기서열 분석을 통하여 시설재배 오이 내 상재균총 군집 특성을 분석하였으며, 수확 시기 및 지역에 따른 상재균총에 대한 정보를 제공하였다. 상재균총 다양성 분석(α-diversity)의 경우 5월 시료에서 더 높은 수치의 Observed OTUs와 Chao1 index가 나타났다. PCoA (β-diversity)분석을 통해서 수확 시기에 따른 상재균총의 차이가 존재함을 확인하였다. Phylum 수준에서는 Proteobacteria, Firmicutes, Actinobacteria가 우점하였고, class 수준에서는 Gammaproteobacteria, Bacilli, Alphaproteobacteria, Actinobacteria가 주로 존재하였다. Genus 수준에서는 시기적인 요인이 주로 상재균총에 영향을 끼치는 것을 확인할 수 있었으며, 일부 지역적 요인의 영향도 관찰 되었다. 5월 시료에서는 Aureimonas, Escherichia, Microbacterium이 11월 시료에서는 Enterococcus, Pseudomonas, Rhizobium이 더 높은 비율을 차지하였다. 이외에도, Acinetobacter, Aerococcus, Aureimonas, Enterobacter, Enterococcus, Escherichia, Pantoea, Pseudomonas, Staphylococcus와 같이 잠재적인 위험성을 가지는 genus가 존재함을 확인하였다.

Keywords

Acknowledgement

이 연구는 충남대학교 학술연구비의 지원을 받아 수행됨.

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