• 한국축산식품학회지
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• 제40권4호
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• pp.668-674
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• 2020

Manuka honey (MH) has been shown anti-bacterial activity against several pathogenic bacteria. However, the inhibitory effect of MH on biofilm formation by Escherichia coli O157:H7 has not yet been examined. In this study, MH significantly reduced E. coli O157:H7 biofilm. Moreover, pre- and post-treatment with MH also significantly reduced E. coli O157:H7 biofilm. Cellular metabolic activities exhibited that the viability of E. coli O157:H7 biofilm cells was reduced in the presence of MH. Further, colony forming unit of MH-treated E. coli O157:H7 biofilm was significantly reduced by over 70%. Collectively, this study suggests the potential of anti-biofilm properties of MH which could be applied to control E. coli O157:H7.

• 한국식품영양학회지
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• 제12권6호
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• pp.564-568
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• 1999

Habituation to alkali condition and susceptibility to antimicrobial agents were investigated to determine methods t inactivation Escherichia coli O157:H7 associated with food poisoning. The investigation showed that Escherichia coli O157:H7growth at pH 9.0 The susceptibilities of Escherichia coli O157:H7 to 13 drugs examined were found highest in regad to saicin and ceftriaxone and lowest in regard to erythromycin and josamycin. No significant changes in minimal inhibitory concen-tration(MIC) values of bactericidal effect was found when saicin and ceftriaxone were irradiated with doses of 5-100KGy.

• 한국축산식품학회지
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• 제36권2호
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• pp.186-193
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• 2016

This study aimed to inhibit Escherichia coli (E. coli) O157:H7 artificially contaminated in fresh meat using bacteriophage. Among 14 bacteriophages, the highly lytic bacteriophage BPECO19 strain was selected to inhibit E. coli O157:H7 in artificially contaminated meat samples. Bacteriophage BPECO19 significantly reduced E. coli O157:H7 bacterial load in vitro in a multiplicity of infection (MOI)-dependent manner. E. coli O157:H7 was completely inhibited only in 10 min in vitro by the treatment of 10,000 MOI BPECO19. The treatment of BPECO19 at 100,000 MOI completely reduced 5 Log CFU/cm² E. coli O157:H7 bacterial load in beef and pork at 4 and 8h, respectively. In chicken meat, a 4.65 log reduction of E. coli O157:H7 was observed at 4 h by 100,000 MOI. The treatment of single bacteriophage BPECO19 was an effective method to control E. coli O157:H7 in meat samples.

• 한국식품영양과학회지
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• 제33권3호
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• pp.571-575
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• 2004

대장균 O157:H7의 백신 생산을 위해서 purity가 높은 lipopolysacharride 분리, 정제를 위한 실험을 실시하였다. 대장균 O157:H7 균주를 확인하기 위해서 shiga toxin을 생산할 수 있는 60 MDa plasmid를 분리하였고, PCR법에 의해 E. coli O157:H7 shiga-like toxin(Stx) 1, 2의 stx gene을 증폭하여 E. coli O157:H7의 특징 (130 bp, 346 bp)을 확인하였다. E. coli O157:H7 LPS의 분리 정제는 페놀추출, 에탄올 분획 및 gel filtration의 간단한 방법을 사용하였다. 마지막으로 SDS-PAGE와 silver nitrate 염색을 이용하여 LPS의 purity를 확인하였다.

• 한국식품위생안전성학회지
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• 제12권1호
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• pp.78-82
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• 1997

Surface swab samples from beef (188), pork (240) and chicken (95) carcasses were collected from slaughterhouse in Kangwon and Kyunggi areas from March through July 1996. The samples were examined on the level of E. coli biotype I relevant to fecal contamination due to unsanitary processing control and the existence of verocytotoxin-producing E. coli (VTEC). E. coli biotype I were confirmed from 38.8% of beef, 40.0% of pork, and 69.5% of chicken carcasses. Little variation was noted among three sampling points; rump, flank and neck of beef, ham, belly and jowls of pork. coli O157:H7 was only confirmed from 2 of 188 beef carcasses. E. coli biotype I. All the isolated E. coli O157 showed positive for vero cell cytotoxicity test. Isolation rate of E. coli O157 in summer was higher than in spring. In case of pork and chicken carcasses, E. coli O157 was isolated in summer only.

• KSBB Journal
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• 제13권2호
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• pp.168-173
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• 1998

Gamma irradiated and non-irradiated Agrimonia pilosa Ledebour were extracted by 70% ethanol. The combined effects of the Agrimonia pilosa Ledebour extract and NaCl on survival of Escherichia coli O157:H7 in tryptic soy broth were investigated. E. coli O157:H7 decreased ca 1 log cycle by the addition of 2% sample extract, and the anthbacterial activity was increased as the concentration of sample extract was increased. The irradiation effect of the sample on antibacterial activity was not observed. On the treatment of NaCl alone, E. coli O157:H7 was inactivated (ca 3~4 log cycle reduction within 48 hr) in more than 7% NaCl. The higher inactivation(ca 5 log cycle reduction within 48 hr) occurred in the presence of 2% sample extract and 5% NaCl than in the addition of each alone. The extracted antibacterial substance was stable in the pH range of 4.0 to 7.0, heat treatment at 121$^\circ C$ for 15 min, and freezing at -18$^\circ C$ and thawing at 37$^\circ C$. There fore, the sample extract, would substantially increase the food-safety in terms of E. coli O157:H7.

• Pediatric Infection and Vaccine
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• 제4권1호
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• pp.73-78
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• 1997

목 적 : Escherichia coli (E. coli) O157은 설사, 출혈성대장염 등을 일으키며, 드물게 용혈성 요독증후군까지 일으키는 세균이다. 미국이나 유럽에서는 세균성설사의 2~3번째로 흔한 원인균이다. 우리나라는 이 세균감염이 거의 없는것으로 알려져 왔으나, 우리나라도 점차 햄버거와 같은 간이음식의 섭취가 늘어나, 이 세균감염이 생겼을 가능성이 있을 것으로 사료되어, 향후 이 세균에 대한 통상적인 변배양 검사의 필요성 여부를 알아보고자 하였다. 방 법 : 1996년 3월부터 1997년 2월까지 6개월 이상된 소아설사 환아의 변배양 검체를 대상으로 하였다. Sorbitol-MacConkey 한천에 배양한 후 형성된 집락 중 무색 집락을 대상으로 E. coli로 동정된 것을 E. coli O157 라텍스 응집검사를 실시하여 응집이 되면 양성으로 판독하였다. 결 과 : 총 317 검체중 11월에 1 검체 (0.3%)에서 Shiga 독소를 생성하지 않는 E. coli O157:NM이 분리되었다. 7세 남아로 2일간의 복통과 1일간의 설사 및 구토를 주소로 입원 한 후 특별한 치료없이 2일후 증상이 호전되어 퇴원하였다. 결 론 : 검사된 모든 대변 검체중 한 검체 (0.3%)만이 E. coli O157이 분리되었으나 Shiga 독소를 생성하지 않는 군주였다. 따라서 이 세균의 분리를 위한 통상적인 변배양 검사는 아직 불필요한 것으로 사료되었다.

• 한국환경보건학회지
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• 제33권5호
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• pp.403-407
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• 2007

The inhibitory effect of the food processing agent on growth of Escherichia coli O157:H7, Salmonella Enteritidis, and Listeria monocytogenes was performed with organic acid, and combination of citric acid, acetic acid, propionic acid and vanillic acid. The minimun inhibitory concentration(MIC) of propionic acid was 5,000 ppm in E. coli O157:H7, 2,500 ppm in Salmonella Enteritidis and Listeria monocytogenes. MIC of citric acid was 10,000 ppm in E. coli O157:H7 and Salmonella Enteritidis, 2,500 ppm in Listeria monocytogenes. MIC of acetic acid was 2,500ppm, while in vanillic acid was 5,000 ppm in Escherichia coli O157:H7, Salmonella Enteritidis, and Listeria monocytogenes. MIC of combined organc acid in E. coli O157:H7 were 2,500ppm in PC, 1,250 ppm in PA, PV, CA, CV and AV. MIC of combined organc acid in Salmonella Enteritidis were 2,500 ppm in PC, PA, PV, CA, and CV, 1,250 ppm in AV. MIC of combined organc acid in Listeria monocytogenes were 1,250 ppm in all treatment group. MIC of combined treatment of three organc acid in E. coli O157:H7, S. Enteritidis and L. monocytogenes were 1,250 ppm in PCA, PCV, PAV and CAV. The inhibitory effect of organc acid in E. coli O157:H7, S. Enteritidis and L. monocytogenes could be confirmed from the result of this experiment. Therefore, it was expected that the food process would increase or maintain by using organic acid.

• 한국식품위생안전성학회지
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• 제12권3호
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• pp.175-180
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• 1997

Escherichia coli O157:H7 and Salmonella ser. typhimurium are pathogens involved in food poisoning in numerous countries. This study aimed to obtain knowleges on the survival of E. coli O157:H7 KSC 109 and S. ser. typhimurium ATCC 14028 in fermentedmilk products which were on sale in Suwon Yakult supplier. To the final concentration of 103~104 cfu/$m\ell$ of E. coli O157:H7 KSC 109 or S. wer. typhimurium ATCC 14028 in the fermented milks, Metchnikoff, Ace, Yakult, Mastoni and Super 100 were inoculated with these pathogens and then were stored at 4$^{\circ}C$ and viable cells of these pathogens were periodically counted. The results showed that the survival of two pathogens differed in the different types of fermented milks tested. Number of suriviving E. coli O157:H7 KSC 109 and S. ser. typimurium ATCC 14028 cells (initial inoculum, 103~104 cfu/$m\ell$) were decreased to 101, 102 cfu/$m\ell$ in Ace after 100 hours, and were decreased gradually to 101 cfu/$m\ell$ in Yakult after 250 hours. In the other fermented milks, viable cells of E. coli O157:H7 KSC 109 was not drastically decreased but those of S. ser. typhimurium ATCC 14028 was decreased gradually to 102 (Mastoni), and to 101 cfu/$m\ell$ (Super 100) after 250 hours. It appeared that S. ser. typhimurium ATCC 14028 was more susceptible than E. coli O157:H7 KSC 109 at low pH. Vibale cells of E. coli O157:H7 KSC 109 was not drastically decreased in most of fermented milks tested except Ace and Yakult, but in general, S. ser. typhimurium ATCC 14028 was drastically decreased in most of the fermented milks. The major ingibition factor against these pathogens in the fermented milks during storage at 4$^{\circ}C$ appeared to be the acidity and the metabolites produced by the starters bacteria used in fermented milk products.

• Journal of Microbiology and Biotechnology
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• 제16권8호
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• pp.1169-1173
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• 2006

Imaging ellipsometry (IE) for detection of binding of Escherichia coli O157:H7 (E. coli O157:H7) to an immunosensor is reported. A protein G layer, chemically bound to a self-assembled layer of 11-mercaptoundecanoic acid (11-MUA), was adopted for immobilization of monoclonal antibody against E. coli O157:H7 (Mab). The immobilization of antibody was investigated using surface plasmon resonance. To fabricate antibody spots on a gold surface, protein G solution was spotted onto the gold surface modified with an 11-MUA layer, followed by immobilizing Mab on the protein G spot. Ellipsometric images of the protein G spot, the Mab spot, and Mab spots with binding of E. coli O157:H7 in various concentrations were acquired using the IE system. The change of mean optical intensity of the Mab spots in the ellipsometric images indicated that the lowest detection limit was $10^3$CFU/ml for E. coli O157:H7. Thus, IE can be applied to an immunosensor for detection of E. coli O157:H7 as a detection method with the advantages of allowing label-free detection, high sensitivity, and operational simplicity.