Microbiology and Biotechnology Letters (한국미생물·생명공학회지)

The Korean Society for Microbiology and Biotechnology (한국미생물·생명공학회)
권호 표지
DOI QR코드

DOI QR Code

Technological Characteristics and Safety of Enterococcus faecium Isolates from Meju, a Traditional Korean Fermented Soybean Food

메주 유래 Enterococcus faecium 균주의 기능적 특성 및 안전성

  • Oh, Yeongmin (Department of Food Science and Biotechnology, Kyonggi University) ;
  • Kong, Haram (Department of Food Science and Biotechnology, Kyonggi University) ;
  • Jeong, Do-Won (Department of Food and Nutrition, Dongduk Women's University) ;
  • Lee, Jong-Hoon (Department of Food Science and Biotechnology, Kyonggi University)
  • 오영민 (경기대학교 식품생물공학과) ;
  • 공하람 (경기대학교 식품생물공학과) ;
  • 정도원 (동덕여자대학교 식품영양학과) ;
  • 이종훈 (경기대학교 식품생물공학과)
  • Received : 2020.12.15
  • Accepted : 2021.01.05
  • Published : 2021.06.28
Download PDF
⟨ Previous Next ⟩

Abstract

In this study, we assessed the technological characteristics and safety of 88 Enterococcus faecium strains isolated from meju; the strains possess the glutamate decarboxylase gene gadA/B involved in γ-aminobutyric acid production. The study was conducted to evaluate the possibility of introducing E. faecium meju isolates as food fermentation starters. We observed that a NaCl concentration of 6% (w/v) facilitated the growth and acid production of all strains. At a NaCl concentration of 7%, 21 strains (24%) exhibited a low growth rate, 72 strains (82%) a weak acid production, and 16 strains (18%) showed no acid production. All strains exhibited protease activity at a NaCl concentration of 4%. At a NaCl concentration of 5%, 86 strains exhibited weak activity, and one strain showed no protease activity. We could not detect any lipase activity in the investigated strains. None of the strains exhibited an acquired antibiotic resistance to the seven antibiotics tested in the present study, namely ampicillin, chloramphenicol, ciprofloxacin, gentamicin, penicillin G, tetracycline, and vancomycin. We could identify the Enterococcus endocarditis antigen gene efaA and the tyrosine decarboxylase gene tdc contributing to tyramine production, in 88 meju isolates. We could not detect the Enterococcus surface protein gene esp, which is specifically possessed by human-originated E. faecium strains, in any of the 88 strains tested in the study.

γ-Aminobutyric acid 생성에 관여하는 glutamate decarboxylase 유전자 gadA/B를 보유한 메주 유래 Enterococcus faecium 88균주를 대상으로 기능적 특성 및 안전성 평가를 진행하여 메주 유래 E. faecium의 발효식품용 종균으로써의 활용 가능성을 검토하였다. 6% NaCl 농도(w/v)에서 모든 균주의 생장 및 산 생성이 확인되었다. 7% NaCl 농도에서는 21균주(24%)가 낮은 생장을 나타냈으며, 72균주(82%)가 약한 산 생성 활성을 나타냈고, 16균주(18%)는 산생성을 나타내지 않았다. 4% NaCl 농도에서는 모든 균주가 단백질 분해 활성을 나타냈지만, 5% NaCl 농도에서 86균주(98%)가 약한 활성을 나타냈고, 1균주(1%)는 활성을 나타내지 않았다. 지방 분해 활성은 모든 균주에서 나타나지 않았다. 모든 균주가 7종의 항생제(ampicillin, chloramphenicol, ciprofloxacin, gentamicin, penicillin G, tetracycline, vancomycin)에 대해 획득형 항생제 내성을 나타내지 않았다. Enterococcus 심내막염 항원 유전자 efaA 및 tyramine 생성에 관여하는 tyrosine decarboxylase 유전자 tdc가 메주 유래 88균주에서 발견되었지만, 사람 기원 E. faecium 균주가 특이적으로 보유하고 있는 Enterococcus surface protein 유전자 esp는 발견되지 않았다.

Keywords

Acknowledgement

This research was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF), funded by the Ministry of Education (NRF-2016R1D1A1B01011421 and NRF2019R1A2C1003639). Haram Kong was supported by Kyonggi University's Graduate Research Assistantship 2021.

References

  1. Klein G. 2003. Taxonomy, ecology and antibiotic resistance of enterococci from food and the gastro-intestinal tract. Int. J. Food Microbiol. 88: 123-131. https://doi.org/10.1016/S0168-1605(03)00175-2
  2. Wheeler AL, Hartel PG, Godfrey DG, Hill JL, Segars WI. 2002. Potential of Enterococcus faecalis as a human fecal indicator for microbial source tracking. J. Environ. Qual. 31: 1286-1293. https://doi.org/10.2134/jeq2002.1286
  3. Giraffa G. 2003. Functionality of enterococci in dairy products. Int. J. Food Microbiol. 88: 215-222. https://doi.org/10.1016/S0168-1605(03)00183-1
  4. Franz CM, Holzapfel WH, Stiles ME. 1999. Enterococci at the crossroads of food safety? Int. J. Food Microbiol. 47: 1-24. https://doi.org/10.1016/S0168-1605(99)00007-0
  5. Zheng B, Tomita H, Inoue T, Ike Y. 2009. Isolation of VanB-type Enterococcus faecalis strains from nosocomial infections: first report of the isolation and identification of the pheromoneresponsive plasmids pMG2200, Encoding VanB-type vancomycin resistance and a Bac41-type bacteriocin, and pMG2201, encoding erythromycin resistance and cytolysin (Hly/Bac). Antimicrob. Agents Chemother. 53: 735-747. https://doi.org/10.1128/AAC.00754-08
  6. Sava IG, Heikens E, Huebner J. 2010. Pathogenesis and immunity in enterococcal infections. Clin. Microbiol. Infect. 16: 533-540. https://doi.org/10.1111/j.1469-0691.2010.03213.x
  7. Johnson AP. 1994. The pathogenicity of enterococci. J. Antimicrob. Chemother. 33: 1083-1089. https://doi.org/10.1093/jac/33.6.1083
  8. Burdychova R, Komprda T. 2007. Biogenic amine-forming microbial communities in cheese. FEMS Microbiol. Lett. 276: 149-155. https://doi.org/10.1111/j.1574-6968.2007.00922.x
  9. Munoz-Atienza E, Landeta G, de las Rivas B, Gomez-Sala B, Munoz R, Hernandez PE, et al. 2011. Phenotypic and genetic evaluations of biogenic amine production by lactic acid bacteria isolated from fish and fish products. Int. J. Food Microbiol. 146: 212-216. https://doi.org/10.1016/j.ijfoodmicro.2011.02.024
  10. Trivedi K, Borkovcova I, Karpiskova R. 2009. Tyramine production by enterococci from various foodstuffs: a threat to the consumers. Czech. J. Food Sci. 27: 357-360.
  11. Sarantinopoulos P, Kalantzopoulos G, Tsakalidou E. 2002. Effect of Enterococcus faecium on microbiological, physicochemical and sensory characteristics of Greek Feta cheese. Int. J. Food Microbiol. 76: 93-105. https://doi.org/10.1016/S0168-1605(02)00021-1
  12. Dhakal R, Bajpai VK, Baek KH. 2012. Production of gaba (γ-aminobutyric acid) by microorganisms: a review. Braz. J. Microbiol. 43: 1230-1241. https://doi.org/10.1590/S1517-83822012000400001
  13. Canganella F, Paganini S, Ovidi M, Vettraino AM, Bevilacqua L, Massa S, et al. 1997. A microbiology investigation on probiotic pharmaceutical products used for human health. Microbiol. Res. 152: 171-179. https://doi.org/10.1016/S0944-5013(97)80009-2
  14. Jang M, Jeong DW, Lee JH. 2019. Identification of the predominant Bacillus, Enterococcus, and Staphylococcus species in meju, a spontaneously fermented soybean product. Microbiol. Biotechnol. Lett. 47: 1-5. https://doi.org/10.4014/mbl.1804.04021
  15. Kim HM, Chung DR, Cho SY, Huh K, Kang CI, Peck KR. 2020. Emergence of vancomycin-resistant Enterococcus faecium ST1421 lacking the pstS gene in Korea. Eur. J. Clin. Microbiol. Infect. Dis. 39: 1349-1356. https://doi.org/10.1007/s10096-020-03853-4
  16. Lim HS, Cha IT, Lee H, Seo MJ. 2016. Optimization of γ-aminobutyric acid production by Enterococcus faecium JK29 isolated from a traditional fermented foods. Microbiol. Biotechnol. Lett. 44: 26-33. https://doi.org/10.4014/mbl.1512.12004
  17. Yu P, Ren Q, Wang X, Huang X. 2019. Enhanced biosynthesis of γ-aminobutyric acid (GABA) in Escherichia coli by pathway engineering. Biochem. Eng. J. 141: 252-258. https://doi.org/10.1016/j.bej.2018.10.025
  18. Jeong M, Jeong DW, Lee JH. 2015. Safety and biotechnological properties of Enterococcus faecalis and Enterococcus faecium isolates from Meju. J. Korean Soc. Appl. Biol. Chem. 58: 813-820. https://doi.org/10.1007/s13765-015-0110-2
  19. Jeong DW, Cho H, Lee H, Li C, Garza J, Fried M, et al. 2011. Identification of the P3 promoter and distinct roles of the two promoters of the SaeRS two-component system in Staphylococcus aureus. J. Bacteriol. 193: 4672-4684. https://doi.org/10.1128/JB.00353-11
  20. Sarkar PK, Cook PE, Owens JD. 1993. Bacillus fermentation of soybeans. World J. Microbiol. Biotechnol. 9: 295-299. https://doi.org/10.1007/BF00383066
  21. Besson I, Creuly C, Gros JB, Larroche C. 1997. Pyrazine production by Bacillus subtilis in solid-state fermentation on soybeans. Appl. Microbiol. Biotechnol. 47: 498-495.
  22. Jeong DW, Heo S, Lee B, Lee H, Jeong K, Her JY, et al. 2017. Effects of the predominant bacteria from meju and doenjang on the production of volatile compounds during soybean fermentation. Int. J. Food Microbiol. 262: 8-13. https://doi.org/10.1016/j.ijfoodmicro.2017.09.011
  23. Jeong DW, Jeong K, Lee H, Kim CT, Heo S, Oh Y, et al. 2020. Effects of Enterococcus faecium and Staphylococcus succinus starters on the production of volatile compounds during doenjang fermentation. LWT-Food Sci. Technol. 122: 108996. https://doi.org/10.1016/j.lwt.2019.108996
  24. Katz M, Medina R, Gonzalez S, Oliver G. 2002. Esterolytic and lipolytic activities of lactic acid bacteria isolated from ewe's milk and cheese. J. Food Prot. 65: 1997-2001. https://doi.org/10.4315/0362-028X-65.12.1997
  25. Ammor MS, Florez AB, van Hoek AH, de Los Reyes-Gavilan CG, Aarts HJ, Margolles A, et al. 2008. Molecular characterization of intrinsic and acquired antibiotic resistance in lactic acid bacteria and bifidobacteria. J. Mol. Microbiol. Biotechnol. 14: 6-15. https://doi.org/10.1159/000106077
  26. Singh KV, Coque TM, Weinstock GM, Murray BE. 1998. In vivo testing of an Enterococcus faecalis efaA mutant and use of efaA homologs for species identification. FEMS Immunol. Med. Microbiol. 21: 323-331. https://doi.org/10.1111/j.1574-695X.1998.tb01180.x
  27. Mohamed JA, Huang W, Nallapareddy SR, Teng F, Murray BE. 2004. Influence of origin of isolates, especially endocarditis isolates, and various genes on biofilm formation by Enterococcus faecalis. Infect. Immun. 72: 3658-3663. https://doi.org/10.1128/IAI.72.6.3658-3663.2004
  28. Eaton TJ, Gasson MJ. 2001. Molecular screening of Enterococcus virulence determinants and potential for genetic exchange between food and medical isolates. Appl. Environ. Microbiol. 67: 1628-1635. https://doi.org/10.1128/AEM.67.4.1628-1635.2001
  29. Cariolato D, Andrighetto C, Lombardi A. 2008. Occurrence of virulence factors and antibiotic resistances in Enterococcus faecalis and Enterococcus faecium collected from dairy and human samples in North Italy. Food Control 19: 886-892. https://doi.org/10.1016/j.foodcont.2007.08.019
  30. Ladero V, Fernandez M, Calles-Enriquez M, Sanchez-Llana E, Canedo E, Cruz Martin MC, et al. 2012. Is the production of the biogenic amines tyramine and putrescine a species-level trait in enterococci? Food Microbiol. 30: 132-138. https://doi.org/10.1016/j.fm.2011.12.016
  31. Bhardwaj A, Gupta H, Iyer R, Naresh K, Malik RK. 2009. Tyramineproducing enterococci are equally detected on tyramine production medium, by quantification of tyramine by HPLC, or by tdc gene-targeted PCR. Dairy Sci. Technol. 89: 601-611. https://doi.org/10.1051/dst/2009040