• Korean Journal of Soil Science and Fertilizer
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• v.45 no.4
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• pp.560-564
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• 2012

This study was undertaken to assess the microbiological quality and prevalence of pathogens in organic vegetables produced in Korea. A total of 189 organically grown vegetable samples (perilla leaf 50, lettuce 50, tomato 39, cucumber 50) were analyzed for the presence of aerobic plate count, Escherichia coli O157:H7, Salmonella spp., Staphylococcus aureus, Listeria monocytogenes, and Yersinia enterocolitica. The total aerobic plate counts were in the range of 4.2 to $7.7log\;CFU\;g^{-1}$ for perilla leaf, 5.0 to $8.0log\;CFU\;g^{-1}$ for lettuce, 4.0 to $7.5log\;CFU\;g^{-1}$ for tomato, and 6.6 to $8.6log\;CFU\;g^{-1}$ for cucumber. The highest counts were found in cucumber. E. coli O157:H7, Salmonella spp., S. aureus, L. monocytogenes, and Y. enterocolitica were not detected from any organically grown vegetable samples. This research suggests that continuous monitoring in organic vegetables is required to improve fresh produce safety.

• Microbiology and Biotechnology Letters
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• v.43 no.4
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• pp.307-313
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• 2015

Unpolished rice (UR) is considered to be a healthy alternative to white rice when coping with chronic diseases. In the present study, the fermented slurry of unpolished rice (FSUR) was evaluated with respect to its antimicrobial activities and biochemical characteristics, including the quantities of sugar, total soluble sugar, organic acids, free amino acids, pH, and physiological activity. The antimicrobial efficiency of FSUR was assessed using the paper disc-agar diffusion method. FSUR exhibited strong antimicrobial activity against six pathogenic bacterial strains (Staphylococcus aureus, Escherichia coli, Listeria monocytogenes, Pseudomonas aeruginosa, Salmonella typhimurium, and Yersinia enterocolitica) and two fermentation strains (Gluconacetobacter intermedius and Lodderomyces elongisporus). The antimicrobial activity of FSUR was higher than the commercial antibiotics, carbenicillin ($50{\mu}g/ml$) and tetracycline ($50{\mu}g/ml$) against S. aureus, E. coli, L. monocytogenes, P. aeruginosa, S. typhimurium, Y. enterocolitica, and L. elongisporus. Also FSUR had a high antioxidant activity. The microorganisms were isolated from FSUR using tryptic soy broth and yeast extract-peptone-dextrose agar media. The isolated microorganisms were characterized using physiological and biochemical analyses as well as by 16S rRNA gene sequencing and phylogenic analysis. 16S rRNA gene sequence analysis showed that the isolated microorganisms had a high similarity to G. intermedius, Lactobacillus casei, Lactobacillus plantarum, and Acetobacter peroxydans.

• Journal of Food Hygiene and Safety
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• v.13 no.4
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• pp.412-418
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• 1998

It was perfomed to investigate for Yersinia species from 2,841 spring waters in Seoul, from 1994 to 1998. Of them, Yersinia spp. were isolated 86 isolated (3.3%). Of 86, sixty two isolates(71.1%) were Yesinia enterocolitica, followed by Y. aldovae (11 strains), Y. pseudotuberculosis (5 strains), Y. frederiksenii (3 strains), unclassified Yersinia spp. (5 strains). Yersinia spp. were highest isolated from Nowon-Gu (22 samples asd Bukhan Mountain Park isolated(18 samples). We tested 1.186 samples for SPC and colifrom from 1996 to 1998. of these tests, the positive rate of coliform was 23.6%, SPC, 9.1%, and either coliform of SPC positive 27.1%. The positive rates of coliform and SPC were decreased 26.7%, 12.7% in 1996, 25.8%, 6.3% in 1997 and 18.1%, 7.6% in 1998 , rerspectively. Of Y. enterocolitica, 78% was resistant to ampicillin and carbenicillin. In the case of Y. aldovae, only 3 of 11 isolated were resistant to carbenicillin. Y. pseudotuberculosis were resistant to colistin. Also Y. frederiksenii to carbenicillin. There were many spring waters of Y. enterocolitical isolated from Nowon-Gu and Buk-han Mountain Park. So, it needs to clean the environment of those regions.

• Journal of Food Hygiene and Safety
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• v.32 no.1
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• pp.50-56
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• 2017

The purpose of this study was to investigate the microbiological contamination of water and drinking cups in springs and to estimate the toxin gene, enterotoxin production ability and antibiotic susceptibility of foodborne pathogens. Ten spring water and 34 drinking cups were tested. The average number of total aerobic bacteria and coliform bacteria in spring water were 1.8 log CFU/mL and 1.2 log CFU/mL, and in drinking cups were $4.7log\;CFU/100cm^2$ and $1.7log\;CFU/100cm^2$. Salmonella spp., Staphylococcus aureus, E. coli O157:H7, Listeria monocytogenes, Vibrio parahaemolyticus, Yersinia enterocolitica were not isolated from all of samples but Bacillus cereus was detected in 5 (14.7%) of 34 drinking cups. The nheA and entFM genes were major enterotoxin genes in B. cereus isolated from drinking cups. All of B. cereus tested in this study produce non-heamolytic enterotoxin but only 2 isolates possessed heamolysin BL enterotoxin producing ability. B. cereus was resistant to ${\beta}-lactam$ antibiotics. These results revealed that the sanitary conditions of drinking cups in spring should be improved promptly. The substitution carrying a personal drinking cup for the public drinking cups equipped in springs is suggested to prevent food-borne illness.

• Korean Journal of Veterinary Service
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• v.33 no.2
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• pp.135-141
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• 2010

Bovine brucellosis, an important zoonosis, is diagnosed with serological tests such as the RBT, TAT using inactivated whole bacterial cells or bacterial lipopolysaccharide (LPS) antigen in Korea. However, a strong cross-reaction between Brucella spp. and Yersinia enterocolitica O9 in these tests has seriously complicated the diagnosis of animal brucellosis because Brucella spp. shares common antigenic determinants with Y. enterocolitica O9 in the smooth LPS region. In this study, Brucella-field strains were isolated from Brucellapositive Hanwoo in Kimhae, Korea and outer membrane protein (omp) which has low cross-reaction with Y. enterocolitica O9 and high immunogenicity was extracted from the field strains Then we compared ELISA using the extract with RBT-TAT. Fifteen field strains were isolated from 47 supra-mammary-lymph nodes, which were collected from 18 farms. Isolation rate was 32%. Brucella-specific antigen was identified by performing SDS-PAGE or Western blotting on extracted omp with at 0.5% n-lauroylsarcosine One hundred and ninety-two serum-samples were used in the experiment: 142 negative and 50 positive samples verified by RBT-TAT. According to ELISA results, 127 samples were negative and 15 appeared positive among 142 negatives by RBT-TAT, while 42 samples were positive and 8 were negative among 50 positives by RBT-TAT. Therefore, it showed 89.4% of specificity and 84% of sensi-tivity. Through the current experiments, we could set up an ELISA based on the omp which has low cross-reaction and high immunogenicity and concluded that the omp could be a good material for accurate diagnosis of bovine brucellosis.

• Korean Journal of Food Science and Technology
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• v.35 no.1
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• pp.97-102
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• 2003

Raw and washed spinaches were tested to evaluate the incidences of Aeromonas hydrophila, Escherichia coli O157:H7, Plesiomonas shigelloides, Pseudomonas aeruginosa, Salmonella spp., Shigella spp., Yersinia enterocolitica, Bacillus cereus, Campylobacter jejuni, Clostridium perfringens, Listeria monocytogenes, and Staphylococcus aureus. Four pathogenic bacteria were isolated from spinach samples, and identified by morphological and biochemical methods, including API and ATB identification systems. Isolates from MacConkey, Cereus Selective, Clostridium Perfringens, and Baird-Parker agar media were in 99.9, 99.8, 99.9, and 97.8% agreements with A. hydrophila, B. cereus, C. perfringens, and S. aureus at the species level, respectively. SET-RPLA revealed, among the five strains of S. aureus isolates, two produced type A enterotoxin. All five strains of B. cereus isolates produced enterotoxin as revealed with CRET-RPLA.

• Food Science and Preservation
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• v.12 no.5
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• pp.470-475
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• 2005

Antimicrobial activities of pyroligneous liquor were investigated by determining Minimal Inhibitory Concentration (MIC). The solvent extracts of pyroligneous liquor, which were extracted by using solvents with different polarities such as hexane, ethylacetate, or butanol. The activities were examined by disc diffusion method using MIC against 7 food poisoning microbe type strains. Antimicrobial activities were shown in hexane, ethylacetate, butanol, and aqueous fractions of pyroligneous liquor. Among the four fractions, ethylacetate fraction showed the highest inhibitory effect on the microorganism such as Shigella sonnei, and Yersinia enterocolitica at the concentration of 2.0 mg/disc. The purified P-1 and P-2 fractions isolated by silica gel column chromatography from ethylacetate fraction of pyroligneous liquor had the highest antimicrobial activity. The total phenolic compounds content in ethylacetate, hexane, butanol, and aqueous fraction was 488.3 mg/g, 403.8 mg/g, 83.6mg/g, and 74.5 mg/g, respectively. Taken together, these results suggest that the ethyl acetate fraction could be suitable for the development of isolation and identification of antimicrobial compound from pyroligneous liquor, resulting from the above antimicrobial activity.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2003.07a
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• pp.421-426
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• 2003

The Immunosensor based on antigen-antibody binding have been developed for detecting several analytes including antigen, small molecules, and cell. This method can be rapid and show very good detection limits. For Implementation of immunosensor, technologies for immobilization of antibody onto solid surface and detection of protein-protein binding must be developed. (an ellipsis)

• Proceedings of the Korean Society of Food and Cookery Science Conference
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• 2003.10a
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• pp.96-96
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• 2003

무화과의 성숙정도에 따른 항균활성을 검색하고자 메탄올과 용매계통분획물에 대하여 8종의 식중독균(Listeria monocytogenes, Staphylococcus aureus, Escherichia coli O157:H7, Yersinia enterocolitica, Salmonella enteritidis, Vibrio parahaemolyticus, Salmonella typhimurium, Escherichia coli)에 대한 성장억제 효과를 검색하였다. 미숙, I, II기 및 성숙 무화과의 메탄올추출물은 10mg/mLshd도에서 L. monocytogenes, V. parahaemolyticus, E. coli O157:H7과 E. coli에 대해 강한 저해활성을 나타내었다. (중략)

• Food Science of Animal Resources
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• v.24 no.2
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• pp.176-181
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• 2004

The specificity of sandwich enzyme-linked immunosorbent assay (ELISA) to detect Salmonella in milk was determined in this study. The antibodies used in sandwich ELISA were egg yolk immunoglobulin G (IgY) obtained after immunization of hen with outer membrane protein (OMP) fraction from Salmonella typhimurium and rabbit IgG obtained after immunization of rabbit with the purified OMP with the molecular weight of 40,000. The immunoblot assay showed that the IgY reacted strongly with OMP with the molecular weight of 6,000 and the rabbit IgG reacted strongly with OMP with the molecular weights of 40,000, 35,000, and 6,000 from the bacteria including Salmonella which belongs to Enterobacteriaceae. The IgY and rabbit IgG also reacted with other proteins from Salmonella typhimurium in immunoblot assay. Competitive ELISA showed that IgY showed specifity to react with two strains of Salmonella typhimurium and Salmonella cholerasuis but not with Escherichia coli and Yersinia enterocolitica. Two strains of Salmonella typhimurium added to UHT milk showed the highest absorbance of all the bacteria used in the sandwich ELISA. Some strains of Salmonella cholerasuis showed higher absorbances than non-Salmonella bacteria.