• Journal of Food Hygiene and Safety
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• v.28 no.4
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• pp.324-329
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• 2013

This study investigated and evaluated contamination levels of bacteria on tomatoes at farms stage to evaluate potential hazards associated with fresh tomatoes. A total of 170 samples, 90 samples from 5 sampling sites from 18 farms and 80 samples from 1 sampling site from 4 farms every month for four months, were analyzed to enumerate aerobic bacterial counts, coliforms, E. coli, Bacillus cereus, Staphylococcus aureus, Escherichia coli, E. coli O157:H7, Salmonella spp., and Listeria monocytogenes. Aerobic bacterial counts ranged from 0.48 to 6.15 Log CFU/g, with the lowest and the highest bacterial cell counts recorded for A site and E site, respectively. Thirty five percent of the samples from the E site contained more than 2 Log CFU/g. Six samples (6.6%) of 90 samples contained B. cereus less than 1 Log CFU/g. In addition, the contamination level of indicator bacteria and B. cereus in tomatoes were higher on March than on April, May and June (P < 0.05). S. aureus, E. coli, E. coli O157:H7, Salmonella spp. and L. monocytogenes were not detected in the tomato samples. The microbial contamination levels of tomatoes determined in this study may be used as the data for microbiological risk assessment.

• Journal of Food Hygiene and Safety
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• v.35 no.5
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• pp.468-476
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• 2020

We aimed to analyze the microbiological quality of the ready-to-eat (RTE) side dishes collected from traditional markets, supermarkets, and cafeterias in Gyeonggi-do in 2019. A total of 108 samples were analyzed for total aerobic bacterial counts, coliforms and foodborne pathogens depending on place of purchase and cooking methods. Results show that Bacillus cereus was detected in 14 (12.9%) out of 108 samples of side dishes, while no other foodborne pathogens were detected. The mean detected level (range) of total aerobic bacteria depending on place of purchase was 5.8 log CFU/g (3.0 to 8.2 log CFU/g) for traditional markets, 4.3 log CFU/g (2.4 to 7.8 log CFU/g) for supermarkets, and 3.80 log CFU/g (0.0 to 6.8 log CFU/g) for cafeterias, indicating that there was a significant (P<0.05) difference in total aerobic bacterial counts among places of purchase. Among the samples, the highest counts of total aerobic bacteria and coliforms were detected in saengchae (raw vegetables), followed by namul (seasoned herbs, vegetables), bokkeum (stir-fried foods), and jorim (foods cooked in soy sauce). The growth of total aerobic bacteria in seasoned soybean sprouts was inhibited when the sprouts were stored at 4℃ up to 24 h, whereas bacteria rapidly grew at 20 and 35℃ after 3 and 6 h, respectively. These results reveal that storage temperature might play a significant role for the microbiological quality of seasoned soybean sprouts when they are sold in markets. Thus, this study suggests that RTE side dishes should be stored at refrigerated temperature when being sold at markets as well as after purchasing to improve their microbiological quality.

• Journal of Nutrition and Health
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• v.47 no.3
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• pp.214-220
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• 2014

Purpose: The purpose of this study was to assess hygiene status of meals for poorly-fed children through microbiological quality. Methods: Meals were provided by two social enterprises, one franchise, and one convenience store. There were a total of six meal samples; two samples (social enterprise meal 1; SEM 1, social enterprise meal 2; SEM 2) from two social enterprises, respectively, two samples (franchise meal 1; FM 1, franchise meal 2; FM 2) from one franchise, and two samples (convenience store meal 1; CSM 1, convenience store meal 2; CSM 2) from one convenience store. Microbiological analysis and assessment were performed by Korean food standards codex (KFSC). Results: General bacteria and E. coli in SEM 1 were detected, but the levels were not over KFSC, and Coliform less than $9.2{\times}10$ CFU/g was also detected in seasoned bean sprouts of SEM 1. General bacteria was detected at $1.6{\times}10^6$ CFU/g in cabbage kimchi of SEM 2. Coliform was detected in cabbage kimchi, squid cutlet, stir-fried pork, and fried chicken of FM1 and 2, but the levels were not over KFSC. In addition, S. aureus was detected in cabbage kimchi and seasoned dried white radish of FM 1 and 2 ($9.8{\times}10^2$ CFU/g, $9.4{\times}10^3$ CFU/g respectively), thus was over KFSC. B. cereus was detected in stir-fried pork and fried chicken ($1.2{\times}10^3$ CFU/g, $1.5{\times}10^3$ CFU/g respectively) of FM 1 and 2, thus was over KFSC. Finally, S. aureus was detected in stir-fried dried squid, seasoned spicy chicken, and stir-fried kimchi of CSM 1 and 2, and was over KFSC too ($9.5{\times}10^4$ CFU/g, $2.4{\times}10^2$ CFU/g, $1.3{\times}10^3$ CFU/g respectively). Conclusion: Results of this study suggest that systemic management of hygiene is necessary to safely providing meals to poorly-fed children.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.10 no.1
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• pp.115-125
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• 2000

Three major hospitals with over 500 beds located in and near Seoul were surveyed for airbone microorganisms from February 1, 1998 to February 18, 1998. The purpose of the study was to identify and quantify microbiological organisms circulating in the air of three different areas in the hospitals. For the study, a RCS air sampler was utilized equipped with two different collection media, the agar strip GK-A for bacteria and the agar strip HS for fungi. The areas investigated were the intensive care unit (ICU) in the Department of internal medicine, the Newborns room in the Department of Obstetrics, and the microbiology laboratory. The results were as follows; 1. The average numbers of general microbiological particles collected on the agar strip GK-A media were $205CFU/m^3$, $232CFU/m^3$, and $128CFU/m^3$ in each hospitals. The highest concentration of $387CFU/m^3$ was found in the ICU of A hospital at 15:00 during the day. Further analysis of the collected bioaerosols by gram staining, revealed that there were gram positive cocci (89.5%), gram positive bacilli (7.2%), gram negative bacilli (2.8%), and fungi (0.5%), in descending order of frequency. 2. Ten different genes were identified from the agar strip GK-A. The most frequently identified organisms were: the Coagulase negative staphylococcus (55.0%), Micrococcus (21.4%), Enterococcus species(10.4%), and Bacillus species (7.2%). A series of antibiotics susceptibility test were conducted against the aforementioned four(4) organisms. Ninety percent of coagulase negative stapylococcus were sensitive to Penicillins. Pathogenic microbes isolated include: Staphylococcus aureus, Acinetobacter species, Klebsiella pneumonia, Klebsiella oxytoca, and Pseudomonas aeroginosa. 3 Although 56.8% of the microorganisms grown on the strip HS media for fungi could not be identified, some of them were successfully identified. The most frequently found fungi were Aspergillus (35.3%), Yeast or Molds (6.2%), and Penicillium (0.7%). Based on the results obtained from the study, it was concluded that some areas in the hospitals had abnormally high bioaerosol concentrations which could be attributed to human activity. Therefore, it is recommended that periodic assessments of indoor bioaerosols aiming to identify the possible sources should be conducted in order to maintain clean indoor environment in the hospitals.

• 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.

• Korean Journal of Microbiology
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• v.49 no.1
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• pp.51-57
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• 2013

As facilities and equipments for learning activities in college campuses are handled by mass public, their contact surfaces may function as major routes of cross-infection of microbial pathogens. However, unlike items in cafeteria which is the typical target for campus hygiene, those surfaces are not under regular surveillance or sanitary maintenance. In this study, I made a quantitative comparison of the risk of being exposed to microbial pathogens from use of learning facilities such as classrooms and library to the risk from use of cafeteria, for about 1,500 students in a college. Regarding total coliforms as surrogate model of bacterial pathogens, exposure rates were estimated for each item in learning facilities and cafeterias by devising deterministic exposure algorithms based on bacterial abundance, contract rates and transfer rates. The exposure rate in cafeterias was 1.0 CFU/day while learning facilities imposed the rate of 0.5 CFU/day, which reaches a half of the exposure rate in cafeterias. However, 70% of students were exposed more in learning facilities than cafeteria because individuals had different frequencies in using cafeteria. Based on the results, some human-contact surfaces of learning facilities, including elevator buttons, may require regular sanitary maintenance. An efficient sanitary maintenance considering seasonality in diversity of pathogens involved with cross-infections is suggested besides improvement of personal hygiene among students.

• Korean Journal of Clinical Pharmacy
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• v.15 no.2
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• pp.75-81
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• 2005

Community acquired pneumonia (CAP) remains a prevalent and potentially life threatening illness. American Thoracic Society and Infectious Disease Society America recommend combination therapies with ${\beta}-lactam$ plus a macrolide or a fluoroquinolone monotherapy for the empirical treatment of CAP. The aim of this study was to compare moxifloxacin monotherapy with cephalosporin plus azithromycin combination therapies. From January 2004 to March 2005, 18 patients in the moxifloxacin group(MG) and 21 patients in the cefuroxime or ceftriaxone plus azithromycin group(CAG) with CAP were retrospectively reviewed with regard to clinical, laboratory and microbiological data. Each patient was stratified into mild (risk class I-II), moderate (risk class III) and severe (risk class VI, V) group according to and PSI (Pneumonia Severity Index) score. Each group was compared for microbiological eradication, clinical assessment, the length of hospital stay. As results, Total 39 patients with CAP were reviewed. The appropriateness of admission was 83.3% in MC vs. 76.2% in CAC. The mean length of the hospital day was for 8.31 days vs. 7.39 days, days switching parenteral to oral antibiotics in 5.19 days vs. 5.28 days, clinical improvement in 2.43 days vs. 2.61 days in MG vs. CAC. Radiological improvement required 3.75 days vs 3.63 days in MG vs. CAG and bacteriological eradication rate at discharge was the same in the both groups. Mortality rate was 11.1% (2 of 18) vs 14.3% (3 of 21) in MG vs. CAG (p=0.77). Drug cost of the mean 5 hospital days requiring parenteral antibiotics was the most inexpensive in moxifloxacin group for the 147,045 won, and ceftriaxone 1g-azithromycin group for the 170,285 won, cefuroxime bid-azithromycin group for the 207,800 won, ceftriaxone 2g-azithromycin group far the 220,570 won, cefuroxime tid-azithromycin group for the 251,700 won. There was no significant statistical difference in clinical, bacterial, radiological cure and hospital days, and switch to oral days. In conclusion, that i.v. moxifloxacin monotherapy was as effective as azithromycin plus cefuroxime or ceftriaxone combination therapies fur the treatment of CAP. In drug cost analysis, moxifloxacin is less expensive than CAG.

• Journal of the Korean Dietetic Association
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• v.12 no.2
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• pp.172-184
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• 2006

This study was aimed to provide safety management guidance by evaluating the microbial quality of cooked dried-seafoods in school foodservice operations. Nineteen seafood items were collected from six elementary schools, those were dried-anchovy, dried-seaweed and dried-fish, which were classified as cooking process. The temperatures at receiving and after cooking were measured and the analyses of cooking processes and microbial quality were performed. The temperatures of all foods after cooking were higher than the temperature limit of $74\^circC$. The number of total aerobic bacteria and S. aureus in dried-anchovy over the limit of $10^5$ and even the level of S. aureus was found to be unsatisfactory. The count of total aerobic bacteria was 2.1x$10^8$ CFU/g and the number of total aerobic bacteria after cooking was over the limit in one school. The level of E. coli (3.1x$10^3$ CFU/g) was over the limit at one school and the number of S. aureus (1.2×$10^4$ CFU/g) was considered as unacceptable. Dried- tangle and green laver were contaminated with total aerobic bacteria showing the over the limit. The numbers of total aerobic bacteria in dried- filefish, pollack and squid were 4.3x$10^6$, 3.4x$10^6$-3.9x$10^7$ and 4.6x$10^5$-4.1x$10^7$ CFU/g, respectively, which were in acceptable or unsatisfactory level. The E. coli in dried- filefish and pollack were over the limit. The total aerobic bacteria levels, 4.6x$10^5$-1.5x$10^6$ CFU/g in dried-pollack and 8.0x$10^5$-2.2x$10^7$ CFU/g in dried-squid, were over the limit after cooking except dried-filefish. The E. coli levels, 4.3x$10^3$ CFU/g in dried-filefish and 2.5x$10^2$ CFU/g in dried-pollack, were over the limit of $10^2$ CFU/g. The numbers of Enterobacteriaceae were either acceptable (3.3x$10^3$ CFU/g) or unsatisfactory (1.6x$10^4$ CFU/g) level in dried-pollack. S. aureus was unsatisfactory level (6.5x$10^4$ CFU/g) in dried-filefish while unacceptable in dried-pollack both before and after cooking. Unacceptable levels of S. aureus, 2.4x$10^4$ and 1.3x$10^5$ CFU/g were found from two schools, respectively. These results suggest that the contamination of raw materials and the seasonings added after cooking should be controlled to manage the microbial safety of cooked dried-seafoods.

• Environmental Analysis Health and Toxicology
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• v.22 no.4
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• pp.313-320
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• 2007

본 연구는 인간의 건강과 식품의 오염을 예방하기 위한 유용한 자료를 얻기 위하여 육류(소고기, 닭고기, 돼지고기)로부터 분리된 staphylococci를 가지고 한국에서 광범위하게 사용되는 6가지 항생제와 daptomycin, linezolid, quinupristin/dalfopristin and tigecycline과 같은 4가지의 신항생제에 대한 항생제 감수성 시험을 수행하였다. 이에 더하여 육류의 세균 오염실태를 조사하기 위하여 총 세균수와 대장균수를 측정하였다. 그 결과 147개의 육류 샘플 중 48%의 샘플에서 일반세균수의 기준에 부적합한 결과가 나타났으며, 대장균수에 대해서는 31%의 샘플에서 기준에 부적합한 결과가 나타났다. 또한 육류의 91%에서 stapylococci가 검출되었으며 이들 staphylococci는 Coagulase Negative Staphylococci (CNS)와 S. aureus로 동정되었다. 분리된 staphylococci의 5.4%가 methicillin (oxacillin)에 내성을 나타내었고, 특히 mupirocin ($MIC_{90},\;>\;12\;{\mu}g/mL$) gentamicin ($MIC_{90},\;64\;{\mu}g/mL$)에 높은 내성을 나타내었다. 그러나 신항생제에 대해서는 methicillin 내성 staphylococci를 포함한 모든 staphylococci 분리균주가 높은 감수성을 나타내었다. 결론적으로 본 연구의 결과들은 육류가 소비자들의 건강에 중요한 위험요소로 작용할 수 있음을 보여주고 있다.

• 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.