• Korean Journal of Veterinary Research
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• v.38 no.3
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• pp.553-558
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• 1998

Using the previous established multiplex PCR (mPCR), the presence of six kinds of staphylococcal superantigen (SAg) genes was investigated for nineteen Staphylococcus aureus isolates from the commercialized meat sources. As a result, only one isolate from pork among 19 S aureus isolates (5.3%) was confirmed as a potential SAg producer and harbored sec gene. The results in this study suggest that meat may not be major contagion of staphylococcal food poisoning (SFP) in Korea and that staphylococcal enterotoxin type C may be associated with the disease. Also, the mPCR method in this study can be a useful genotypic method which can overcome the typical disadvantages of conventional antibody-based methods due to antigenic homology, and furthur survey on food-borne S aureus isolates can provide the important epidemiological data for SFP in Korea.

• Fisheries and Aquatic Sciences
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• v.19 no.10
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• pp.42.1-42.10
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• 2016

The objectives of this study were to identify the histamine-forming bacteria and bacteriocin- producing lactic acid bacteria (LAB) isolated from Myeolchi-jeot according to sequence analysis of the 16S rRNA gene, to evaluate the inhibitory effects of the bacteriocin on the growth and histamine accumulation of histamine-forming bacteria, and to assess the physico-chemical properties of the bacteriocin. Based on 16S rRNA gene sequences, histamine-forming bacteria were identified as Bacillus licheniformis MCH01, Serratia marcescens MCH02, Staphylococcus xylosus MCH03, Aeromonas hydrophila MCH04, and Morganella morganii MCH05. The five LAB strains identified as Pediococcus acidilactici MCL11, Leuconostoc mesenteroides MCL12, Enterococcus faecium MCL13, Lactobacillus sakei MCL14, and Lactobacillus acidophilus MCL15 were found to produce an antibacterial compound with inhibitory activity against the tested histamine-producing bacteria. The inhibitory activity of these bacteriocins obtained from the five LAB remained stable after incubation at pH 4.0-8.0 and heating for 10 min at $80^{\circ}C$; however, the bacteriocin activity was destroyed after treatment with papain, pepsin, proteinase K, ${\alpha}$-chymotrypsin, or trypsin. Meanwhile, these bacteriocins produced by the tested LAB strains also exhibited histamine-degradation ability. Therefore, these antimicrobial substances may play a role in inhibiting histamine formation in the fermented fish products and preventing seafood-related food-borne disease caused by bacterially generated histamine.

• Journal of Dairy Science and Biotechnology
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• v.32 no.2
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• pp.101-104
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• 2014

Food safety is a global health goal, and food-borne disease are a significant public health threat throughout the world. Dairy products are susceptible to contamination through a wide variety of physical, microbial, and chemical hazards. Risks of microbiological hazards are of immediate and serious concern to human health. Milk was inoculated with Bacillus cereus and stored at 10, 15, 20, and $30^{\circ}C$ for 7 days. We monitored the effect of the temperature on growth rate and variance of toxin production. The growth rate of B. cereus was suppressed in low temperature. We confirmed that the growth rate and the toxin production were accelerated when the storage temperature was increased. B. cereus began to produce toxins when the number of bacteria was higher than $10^7CFU/mL$. Therefore, managing the storage temperature of milk is important to inhibit the growth and the toxin production of B. cereus.

• Journal of Preventive Medicine and Public Health
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• v.33 no.1
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• pp.10-16
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• 2000

Objectives : This study was carried out to investigate the sources of infection and modes of transmission of an outbreak of shigellosis that occurred among students of B middle and high school in Bonghwa, Korea from May 1 to 21, 1999. Methods : We conducted questionnaires to 468 students, 38 stalls and 9 food handlers twice times (May 6, May 21) for follow up and secondary attack rate. Personal details and history of illness and exposure to particular foods were sought. And we conducted rectal swab for culture to 243 students, 33 staffs and 9 food handlers. Bacteriological examinations of water in the school were done. Cases were identified as subjects who had diarrhea (two or more loose stools in a 24-hour periods) on or after May 1. Results : A total of 307 cases (attack rate: 59.6%) of 515 subject were identified, including 50 confirmed (46 students and 4 staffs) by S. sonnei. All 9 food handlers denied illness and were had rectal swab for culture at May 6 that were negative for S. sonnei. 146 of 307 reported fever, 156 had tenesmus, 44 reported vomiting, and only 5 of 307 reported blood in the stool. The median duration of diarrhea was 4 days (range: 1-18 days). The mean incubation period until onset of diarrhea was 63 hours (range: 46-144 hours) and the secondary attack rate was 2.8% (43 cases of 1,561 family members). Risk for illness was higher among students who had eaten watered kimchi at March 30 than among those who did not [301(72.7%) of 417 versus 5(9.6%) of 52; RR=7.51;95% CI=3.26-17.31]. Conclusion : The source of infection was estimated to be contaminated watered kimchi by ore or two food hardier who is presumed to be carrier.

• Parasites, Hosts and Diseases
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• v.56 no.5
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• pp.521-525
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• 2018

Rodents are well-known reservoirs and vectors of many emerging and re-emerging infectious diseases, but little is known about their role in zoonotic disease transmission in Bhutan. In this study, a cross-sectional investigation of zoonotic disease pathogens in rodents was performed in Chukha district, Bhutan, where a high incidence of scrub typhus and cases of acute undifferentiated febrile illness had been reported in people during the preceding 4-6 months. Twelve rodents were trapped alive using wire-mesh traps. Following euthanasia, liver and kidney tissues were removed and tested using PCR for Orientia tsutsugamushi and other bacterial and rickettsial pathogens causing bartonellosis, borreliosis, human monocytic ehrlichiosis, human granulocytic anaplasmosis, leptospirosis, and rickettsiosis. A phylogenetic analysis was performed on all rodent species captured and pathogens detected. Four out of the 12 rodents (33.3%) tested positive by PCR for zoonotic pathogens. Anaplasma phagocytophilum, Bartonella grahamii, and B. queenslandensis were identified for the first time in Bhutan. Leptospira interrogans was also detected for the first time from rodents in Bhutan. The findings demonstrate the presence of these zoonotic pathogens in rodents in Bhutan, which may pose a risk of disease transmission to humans.

• Journal of Food Hygiene and Safety
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• v.16 no.3
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• pp.159-167
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• 2001

Staphylocorccus aureus is gram positive, facultatively anaerobic, non-sporulative coccus, and positive for coagulase and DNase. The food-poisoning outbreak of Staphylococcus aureus increases in the world, and third occurrence happened in our country. Of 105 isolates (25.4%) obtained 413 focal samples of food-poisoning suspicious patients. In those cases, the enterotoxins were detected from a total of 45 isolates (42.9%), 9 isolates(20.0%) were A type, 33 isolates (73.3%) were H types, 2 isolates (4.4%) were G type and 1 isolate was a I type enterotoxin. Among the isolates possessing staphylococcal enterotoxins, 29 isolates had H type only(64.4%), 5 isolates had A type only and 4 isolates had both A and H type. Two isolates had G type only and 1 isolate had I type only. In the antibiotic susceptibility, 48 isolates (46%) had at least one antibiotic resistance among 105 isolates, 34 isolates (70.8%) were resistant to penicillin. 1 isolate (2.1%) to ampicillin, 3 isolates (6.3%) to erythromycin and kanamycin. Seven were resistant to more than two antibiotics and especially 1 isolate was resistant to penicillin-ampicillin-nitrofurantoin.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.2
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• pp.243-249
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• 2001

This study was investigated to determine the antimicrobial effect of the ethanol extract of Quercus mongolica leaf on microbial growth. The ethanol extract at the concentration of $250\;\mu\textrm{g}/mL\;and\;500\;\mu\textrm{g}/mL$ inhibited the growth of gram positive and gram negative food-borne disease bacteria for 40 hours in tryptic soy broth, respectively. Antimicrobial activity of the ethanol extract from Quercus mongolica leaf was not affected by pH and heat treatment. The comparision between ethanol extract and commercially available preservatives on antimicrobial activity in food system was conducted. When the 0.1% ethanol extract of Quercus mongolica leaf was added to pine needle drink and carrot juice, antimicrobial activity was similar to those of containing 0.05% benzoic acid and 0.5% grapefruit seed extract. Also addition of 2~3% ethanol extract to the soybean paste inhibited the microbial growth up to 7 week, comparable to the inhibition of 2% ethanol. Thus, this results indicate that the ethanol extract of Quercus mongolica leaf may be useful as natural antimicrobial agents.

• Parasites, Hosts and Diseases
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• v.59 no.6
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• pp.615-623
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• 2021

Human sparganosis is a food-borne parasitic disease caused by the plerocercoids of Spirometra species. Clinical diagnosis of sparganosis is crucial for effective treatment, thus it is important to identify sensitive and specific antigens of plerocercoids. The aim of the current study was to identify and characterize the immunogenic proteins of Spirometra erinaceieuropaei plerocercoids that were recognized by patient sera. Crude soluble extract of the plerocercoids were separated using 2-dimensional gel electrophoresis coupled with immunoblot and mass spectrometry analysis. Based on immunoblotting patterns and mass spectrometry results, 8 antigenic proteins were identified from the plerocercoid. Among the proteins, cysteine protease protein might be developed as an antigen for diagnosis of sparganosis.

• Journal of Food Hygiene and Safety
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• v.29 no.4
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• pp.322-326
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• 2014

According to Centers for Disease Control and Prevention (CDC, USA) recently it was reported that the children (< 5 year-old children) were more susceptible to Foodborne-illness. Confectionery products should be strictly controlled because they are children-preferred foods. Ministry of Food and Drug Safety (MFDS, South of Korea) tried to monitor contamination of organisms in confectionery products (such as biscuits, candies, chewing gums and ice candies) distributed in South Korea. MFDS evaluated the levels of indicator organisms: total aerobic bacteria, coliforms, Escherichia coli as well as the levels of food-borne illness organisms: Staphylococcus aureus, Bacillus cereus, Clostridium perfringens. Experimental plans for microbiological test were in accordance with the International Commission on Microbiological Specifications for Food (ICMSF). For this study, 1,005 samples were collected and from Seoul and Gyeongin region, South Korea. The average level of total aerobic bacteria in 1,005 samples was 1.7 log Colony Forming Unit(CFU)/g and the detection rate was 26.8%. The average level of Bacillus cereus was detected in 1.7 log CFU/g and the rate was 0.9%. There was no detection of coliforms, Escherichia coli, Staphylococcus aureus and Clostridium perfringens. The results of this study will be provided as the basic data to set the reasonable microbiological criteria of Korea Food Code.

• Korean Journal of Microbiology
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• v.50 no.4
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• pp.285-295
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• 2014

This study was conducted to survey the epidemiological characteristics and the isolated strains for pathogenic E. coli which was the major causative organisms for food poisoning occurred at school food services in the Gyeonggi-do area during the past three years. We investigated 19 accidents of food-borne disease outbreaks by pathogenic E. coli at school food services from 2010 to 2012. Food-borne disease outbreaks by pathogenic E. coli were usually occurred at direct management type (18 accidents, 95%) and high schools. For the seasonal factors, 13 accidents (65%) were occurred in June to September, especially the end of August and September after the summer holidays. The first patients were occurred on Wednesday (7 accidents, 37%) and Thursday (7 accidents, 37%), and they were mainly reported on Thursday (7 accidents, 37%) and Friday (5 accidents, 26%). The exposure of risk was estimated in Monday (4 accidents, 21%), Tuesday (7 accidents, 37%) and Wednesday (4 accidents, 21%), and kimchi (5 accidents, 50%) was estimated as the food of the high risk responsible for the outbreaks. 98 isolates of pathogenic E. coli consisted of PEC (50%), ETEC (34%), EAEC (15%), and EHEC (1%). The antibiotic resistance of pathogenic E. coli showed in the descending order of ampicilline (40%), nalidixic acid (37%), trimethoprim/sulfamethoxazole (24%), and tetracycline (19%). The antibiotics of second and third generation cephalosporins, cabarpenem, aminoglycosides, and second generation quinolones had antimicrobial susceptibilities and cefalotin, ampicillin/sulbactam and chloramphenicol showed medium resistance at 29%, 25%, and 6% respectively, and 70% of isolates were resistant to more than one antibiotic. By the PFGE analysis, they were classified into nine major groups and 31 profiles with 57% pattern similarity. It was very difficult to find the correlation of antimicrobial susceptibilities and genotype in the small scale-food poisoning, but the similarity of antimicrobial resistance and PFGE patterns in the large scale-food poisoning enabled the outbreaks to estimate the same pathotype of E. coli derived from identical origins.