• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.5
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• pp.694-698
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• 2020

The consumption of Gwamegi, a semi-dried saury Cololabis saira, and its vegetable sides has increased owing to its availability online. Therefore, this study investigated the microbial contamination levels in Gwamegi and its accompanying vegetable sides bought online by measuring total viable bacteria, coliforms, Escherichia coli, Staphylococcus aureus and fungi. The total viable bacteria ranged from 3-5 log CFU/g. The fungi in Gwamegi and garlic were 3.4 and 3.9 log CFU/g, respectively. The positive rate of bacterial contamination was 100% (2-3 log CFU/g) in Gwamegi, cabbage Brassica rapa subsp. pekinensis, and green chili Capsicum annuum, whereas the contamination positive rate was 80% and 60% (< 2 log CFU/g) in chives Allium ascalonicum L. and garlic A. sativum L., respectively. The positive rates of E. coli were 0%, 20%, 60%, and 40% in Gwamegi, green chili, cabbage, and chives, respectively. The contamination levels of E. coli were 1-2 log CFU/g. S. aureus was detected at < 1 log CFU/g in all raw materials. The data on microbial contamination levels may be used for microbial risk assessment of Gwamegi and vegetables for controlling the level of microbial contamination and securing microbiological safety.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.55 no.4
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• pp.437-442
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• 2022

Squid jeotgal is a very popular traditional, salted, and fermented seafood in Korea. Due to the development of a distribution structure, a lot of imported squid jeotgal has recently entered Korea. In this study, we analyzed and compared the microbial contamination levels of domestic and imported squid jeotgal. The total viable bacterial count in domestic and imported jeotgal was 5.20 and 5.38 log CFU/g, respectively. The highest contamination level was 6.94 log CFU/g in one of the imported squid jeotgal samples. Coliforms were not detected in domestic jeotgal but were detected at 50% with 2.21 log CFU/g in imported jeotgal. Escherichia coli and Staphylococcus aureus were not detected (ND: <1 log CFU/g) in both domestic and imported jeotgal. All samples of jeotgal were negative for Bacillus cereus and Clostridium perfringens. The microbial contamination levels determined in the current study may be utilized as primary data to execute microbial risk assessments on domestic and (or) imported jeotgal.

• Food Science of Animal Resources
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• v.36 no.4
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• pp.463-468
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• 2016

Contamination by foodborne pathogens and mycotoxins was examined in 475 eggs and 20 feed samples collected from three egg layer farms, three egg-processing units, and five retail markets in Korea. Microbial contamination with Salmonella species, Escherichia coli, and Arcobacter species was examined by bacterial culture and multiplex polymerase chain reaction (PCR). The contamination levels of aflatoxins, ochratoxins, and zearalenone in eggs and chicken feeds were simultaneously analyzed with high-performance liquid chromatography coupled with fluorescence detection after the post-derivatization. While E. coli was isolated from 9.1% of eggs, Salmonella species were not isolated. Arcobacter species were detected in 0.8% of eggs collected from egg layers by PCR only. While aflatoxins, ochratoxins, and zearalenone were found in 100%, 100%, and 85% of chicken feeds, their contamination levels were below the maximum acceptable levels (1.86, 2.24, and 147.53 μg/kg, respectively). However, no eggs were contaminated with aflatoxins, ochratoxins, or zearalenone. Therefore, the risk of contamination by mycotoxins and microbes in eggs and chicken feeds is considered negligible and unlikely to pose a threat to human health.

• Journal of Environmental Health Sciences
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• v.40 no.2
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• pp.98-104
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• 2014

Objectives: The purpose of this study was to determine airborne bioaerosols such as bacteria and fungi in the kitchens of restaurants, and to assess the effects of thermal factors on the levels of the bioaerosols. Methods: Air samples were taken from kitchens of nine restaurants. An Anderson type air sampler was used for sampling and measurements. Petri dishes filled with a microbiological culture medium (trypticase soy agar for bacteria and Sabouraud dextrose agar for fungi) were used as the sampling surface. Results: The levels of bacterial aerosol measured were $10-10^3CFU/m^3$ and fungal aerosol $10-10^2CFU/m^3$, respectively The mean values of air temperature and relative humidity in the kitchens were $24.6^{\circ}C$ and 46.4%, respectively. Overall, the levels of bacterial aerosol varied by the restaurant type, and fungal aerosol by the business period (p < 0.05). The main effect of air temperature and interaction effect of air temperature and relative humidity onto the bacterial level were significant (p < 0.05), whereas the effects were not significant onto the fungal level. Conclusions: The results indicate a wide variation in the levels of bioaerosols among different kitchens. The observed differences in bioaerosol levels in the kitchens reflect different periods of use. The interactions of air temperature and relative humidity onto the bacterial level suggest that constant attention should be paid to avoid peaks of contamination during the summer season.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.56 no.5
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• pp.721-727
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• 2023

This study was conducted to evaluate the level of microbial contamination in smoked salmon products sold in hypermarkets in major metropolitan cities in Korea. Listeria monocytogenes is the primary cause of smoked and raw salmon product recalls. Here, we used L. monocytogenes as a bacterial hygiene indicator and investigated the microbial contamination level of frozen/refrigerated smoked salmon products collected from hyper markets. Contamination levels were analyzed by seasons, manufacturers, and consumption regions. For hygiene indicator bacteria, total bacteria count, coliforms, and Escherichia coli were examined according to the food code established by the Ministry of Food and Drug Safety, and polymerase chain reaction (PCR) was performed to detect Listeria sp. The highest contamination level was observed in spring in Busan among five consumption regions. Listeria was detected at a level of 2.1% among all samples collected. And especially L. monocytogenes was detected in two cases from the samples collected from Daegu and Daejeon. Sanitary standards and specifications should be established according to the contamination level of smoked salmon products investigated in this study, and continuous monitoring is necessary.

• Journal of Preventive Medicine and Public Health
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• v.50 no.3
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• pp.158-164
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• 2017

Objectives: To identify bacterial contamination rates of laryngoscope blades and handles stored in emergency crash carts by hospital and area according to the frequency of intubation attempts. Methods: One hundred forty-eight handles and 71 blades deemed ready for patient use from two tertiary hospitals were sampled with sterile swabs using a standardized rolling technique. Samples were considered negative (not contaminated) if no colonies were present on the blood agar plate after an 18-hour incubation period. Samples were stratified by hospital and according to the frequency of intubation attempts (10 attempts per year) using the ${\chi}^2-test$ and Fisher exact test. Results: One or more species of bacteria were isolated from 4 (5.6%) handle tops, 20 (28.2%) handles with knurled surfaces, and 27 (18.2%) blades. No significant differences were found in microbial contamination levels on the handle tops and blades between the two hospitals and two areas according to the frequency of intubation attempts. However, significant differences were found between the two hospitals and two areas in the level of microbial contamination on the handles with knurled surfaces (p<0.05). Conclusions: Protocols and policies must be reviewed to standardize procedures to clean and disinfect laryngoscope blades and handles; handles should be re-designed to eliminate points of contact with the blade; and single-use, one-piece laryngoscopes should be introduced.

• Korean Journal of Clinical Laboratory Science
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• v.47 no.4
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• pp.279-285
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• 2015

This study studied samples taken off surfaces at three sites (Unit chairs, light handles, cuspidors) of 19 dental hospitals and 28 clinics located in Gyeonggi-do and Incheon, South Korea. The bacterial contamination levels of surfaces were $44.82{\times}10^3CFU/mL$ in cuspidors, higher than in unit chairs ($5.47{\times}10^3CFU/mL$) and light handles ($16.28{\times}10^3CFU/mL$). The values were statistically higher at dental hospitals than at dental clinics, the greater number of patients being associated with the higher bacterial cell count in the cuspidors. The results of identifying the strains isolated purely from surfaces at dental clinic showed Gram positive 47.3% and Gram negative 52.7%. Among Gram positive, the most numberous bacteria were Micrococcus luteus (10.9%), Bacillus pumilus (3.6%), and Staphylococcus aureus (3.6%). Among Gram negative, the most numberous bacteria were Acinetobacter ursingii (5.5%), Brevundimonas diminuta (4.5%), Chryseobacterium (Flavo.) indologenes (CDC IIb) (4.5%), and Methylobacterium sp. (4.5%). This study measures the level of bacterial contamination and identifies the strains isolated in dental clinics. It recognizes the importance of infection control, and the results of the study may be considered as the basis for establishing specific plans for prevention of infection.

• Korean Journal of Veterinary Service
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• v.21 no.2
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• pp.157-161
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• 1998

To get the information of sanitary develoment of beef and pork, we get the result of environmental specimens(slaughter house floors, sewage, etc) in laboratory. 1. After examination of bacterial infection on after-bleeding, after-dismemberment and final products at each stage of cattle slaughter process, we got log 3.80~7.48cfu/$\textrm{cm}^2$ of aerobic plate counts and log 2.60~5.23cfu/$\textrm{cm}^2$ of coliform counts or so from the carcasses after bleeding, but these count levels went down little bit after dismemberment but as we continued study to the final products, the count levels kept sililar in mumbers. 2. At the slaughter process of pigs, the aerobic plate counts and the coliform counts reached such high levels of log 5.59~8.80cfu/$\textrm{cm}^2$ and log 3.31~5.67cfu/$\textrm{cm}^2$, respectively, after bleeding, in general, these count diminished in a big way after scalding, but they increased just little bit from dismemberment to final products. And there were few differences in the contamination levels on the final products no matter what seasonal contaminations after bleeding. 3. Test revealed very low levels of cell counts both on the aerobic plate counts of washing water and in the coliform counts, the former was log 1.00~2.69cfu/$\textrm{cm}^2$ and the later was log 3.30~5.67cfu/$\textrm{cm}^2$, but the contamination levels on the beds of transfering vehicles for carcasses were very high as followes : the aerobic counts was log 4.23~7.20cfu/$\textrm{cm}^2$ and coliform counts was log 2.86~5.20cfu/$\textrm{cm}^2$. 4. Study showed the aeroboc plate counts and the coliform counts get to the highest levels in summer, the second highest one is in fall, the third in spring, lowest in winter. Resulting from the test results proven above we reached this kind of conclusion the bacterial contaminations on eatable carcasses were upto hygienic treatment of carcasses and cleaniness of transfering vehicles at the final stop of slaughter processes rather than upto at any stage of slaughter processes. Therefore we have got to establish alternatives immediately to develo sanitary quality of meat and pork.

• Journal of Environmental Health Sciences
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• v.41 no.6
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• pp.397-404
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• 2015

Objectives: The aim of this study is to investigate microbial contamination in the school food service environment for the assessment of microbial food safety. Methods: We collected both swab samples from tables and desks and airborne bacterial samples from an elementary school (School A) and a high school (School B). Heterotrophic plate count, total coliform, Staphylococcus aureus, and Bacillus cereus were measured with selective media to quantify microbial concentration. PCR assay targeting 16S rRNA genes was performed to identify the strains of S. aureus and B. cereus isolated. In addition, we made a food service checklist for the locations to evaluate the food service environment. A Wilcoxon test was employed to examine the differences in microbial concentration between before lunchtime and afterwards. Results: Heterotrophic plate counts showed higher levels after-lunch compared to before-lunch at School B. However, levels of S. aureus were higher in the after-lunch period (p<0.05) in both classrooms and in the cafeteria in School A. B. cereus was only sparsely detected in School B. Several samples from food dining carts were found to be contaminated with bacteria, and facilities associated with food delivery were found to be vulnerable to bacterial contamination. Although microbial concentrations in the air showed little difference between before- and after-lunchtime in the cafeteria in School A, those in classrooms were greater after-lunchtime at both schools. Conclusion: Our results suggested that the microbial safety in schools after lunchtime of concern. Necessary preventive measures such as hygiene education for students and food handlers should be required to minimize microbial contamination during food service processes in schools.

• Korean Journal of Soil Science and Fertilizer
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• v.47 no.6
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• pp.437-442
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• 2014

Foodborne illness due to the consumption of contaminated raw strawberries is a continuing food safety concern. This study investigated and evaluated contamination levels of bacteria on strawberries at farms stage to evaluate potential hazards associated with fresh strawberries. A total of 315 samples, 105 samples from 5 sampling sites (A to E) of 21 farms and 210 samples from 1 sampling site of 6 farms, was collected every month for four months and analyzed to enumerate aerobic bacterial counts, Coliforms/E. coli, Bacillus cereus and Staphylococcus aureus. In addition, the prevalence study of five pathogens (S. aureus, E. coli, E. coli O157:H7, Salmonella spp. and Listeria monocytogenes) was performed on each sample. Aerobic bacterial counts ranged from 0.48 to 6.36 Log CFU/g, with the highest bacterial cell counts recorded for D and E sites. Coliforms were detected in 71 samples (22.5%) with a minimum of 0.48 cfu/g and a maximum of more than 4 Log CFU/g. B. cereus was detected in 98 samples (31.1%) among total samples analyzed. S. aureus was detected in 2 samples with a minimum of 0.48 Log CFU/g and a maximum of 1.38 Log CFU/g. E. coli, E. coli O157:H7, Salmonella spp. and L. monocytogenes were not isolated from any of the samples. The microbial contamination levels of strawberries determined in this study may be used as the fundamental data for microbiological risk assessment.