• Journal of Food Hygiene and Safety
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• v.32 no.5
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• pp.348-354
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• 2017

Internationally different food safety regulation and standards could cause troubles in trade unless those are built on scientific knowledge. In this research, we monitored the microbial population and analyzed the results to determine the level of microbial contamination in foodstuffs using relatively new statistical analysis (microbiological sampling plan, International Commission on Microbiological Specification for Foods). The goal of this research falls on establishing entirely new standards for various food categories addressed in the Korean "Food Code". Targets for monitoring were indicator organisms (i.e. total aerobic count, coliform and Escherichia coli) and foodborne pathogens (i.e. Bacillus cereus, Staphylococcus aureus and Clostridium perfringens) in ready-to-eat (RTE) products. As the result of the monitoring, total aerobic count, coliform, E. coli, and B. cereus in RTE products were found at the mean values of 2.10 log CFU/g, -0.60 log CFU/g, -1.33 log CFU/g and -1.23 log CFU/g, respectively. S. aureus was detected with the level of -1.35 log CFU/g only in fresh-cut food, while C. perfringens was -1.37 log CFU/g only in ready-to-cook food. Other samples did not have any food borne pathogens. Total aerobic count, B. cereus, S. aureus and C. perfringens satisfied the Food Code (the MFDS). On the basis of the analysis, we proposed a draft of microbial criteria for RTE products.

• Clinical and Experimental Pediatrics
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• v.52 no.10
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• pp.1147-1152
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• 2009

Purpose:To characterize the pathogens and their antibiotic susceptibilities in more than 24-month-old children with urinary tract infection (UTI) and to study the Escherichia coli antimicrobial susceptibility trend. Methods:We retrospectively reviewed the record of more than 24-month-old children with UTI between January 2003 and December 2008. Positive results for 1 bacterial species with a colony count of ${\geq}10^5CFU/mL$ was considered statistically significant. We analyzed uropathogens and their antibiotic susceptibilities. To investigate E. coli antibiotic susceptibility trend, we compared 2 study periods (group A: 2003-2005 versus group B: 2006-2008) using the chi-square test for trend. Results:In all, 63 bacterial isolates were identified in children with febrile UTI. The most common pathogen was E. coli (77.8%). There was no difference in the resistance patterns of uropathogens during the 2 study periods (P>0.05). Antibiotic susceptibility of the E. coli isolates to aztreonam, cefotetan, cefotaxime, ceftriaxone, cefepime, amikacin, and imipenem was >90% to trimethoprim/sulfamethoxazol, 49% and to ampicillin and ampicillin/sulbactam, 20-25%. Over the 2 study period, the E. coli susceptibilities to most antibiotics did not change: the susceptibility to cefuroxime increased from 74.1% to 95.5% (P=0.046) and that to ciprofloxacin increased from 59.3% to 86.4% (P=0.039). Conclusion:Empirical treatment with trimethoprim/sulfamethoxazole, ampicillin, and ampicillin/sulbactam alone appeared to be insufficient in childhood UTI because of the high resistance of E. coli and other gram-negative uropathogens. Antibiotics for empirical therapy should be selected based on the sensitivity and resistance pattern of uropathogens found in a particular region.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.57 no.1
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• pp.15-22
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• 2024

This study assessed microbial contamination in seven fried fish pastes sold in Southeast Asian traditional markets during summer. It measured viable cell count, coliforms, Escherichia coli, fungi, and Staphylococcus spp. It also qualitatively analyzed Vibrio parahaemolyticus, Salmonella spp., Bacillus cereus, Listeria monocytogenes, and Clostridium perfringens. The average viable cell count, coliforms and fungi were detected as 6.34 (3.84-8.13), 2.16 (1.00-3.55), and 3.92 (1.85-7.74) log₁₀ CFU/g, respectively. Staphylococcus spp. was detected at 4.59 (2.10-7.63) log₁₀ CFU/g. Some samples had high contamination levels: viable cell count (8.13 log₁₀ CFU/g), fungi (7.74 log₁₀ CFU/g) and S. aureus (7.63 log₁₀ CFU/g). However, E. coli was not detected in any samples (ND, <1 log₁₀ CFU/g). V. parahaemolyticus, Salmonella spp., B. cereus, L. monocytogenes, and Cl. perfringens were also not detected in the samples. The microbial contamination data provide insight into managing microbial contamination and ensuring the safety of fried fish pastes in traditional summer markets.

• Korean Journal of Food Science and Technology
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• v.43 no.4
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• pp.490-494
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• 2011

Although bacterial outbreaks from ready-to-eat foods have increased, little information is available on microbial quality of sprouts in markets. Fifty sprouts and 30 salads were collected from wholesale markets. Total aerobic count (TAC), coliform, Escherichia coli, and some pathogens were detected. TAC for sprouts was 7.95 log CFU/g and 6.70 for salads, indicating that sprouts were more contaminated by 1 log CFU/g than that of salads. The numbers of coliform were 6.69 log CFU/g for sprouts and 5.42 for salads. E. coli was detected in 16 of 50 sprout samples at 2.38 log CFU/g and eight of 30 salads at 2.21 log CFU/g. Bacillus cereus was detected in 29 of 50 sprout samples and 16 of 30 salads, and the counts were mostly <3 log CFU/g. Salmonella, Staphylococcus aureus, Listeria monocytogenes, Campylobacter jejuni, and Clostridium perfringens were not detected. Therefore, although pathogens may not be a high risk for these foods, the high TAC and E. coli contamination require improved production and distribution methods, particularly for sprouts.

• Journal of Microbiology and Biotechnology
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• v.19 no.10
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• pp.1238-1243
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• 2009

The susceptibilities of major enterohemorrhagic Escherichia coli (EHEC) strains to antimicrobial agents and the cytotoxicity of these agents were examined using a total of 38 strains of E. coli O26, O111, and O157, which are the major serogroups of EHEC. Among the 38 strains, 35, 36, and 36 were susceptible to amikacin, imipenem, and norfloxacin, respectively. These antimicrobial agents were further examined to determine their cytotoxicity on Vero cells as well as their effect on the release of Shiga toxins along with trimethoprim/sulfamethoxazole. Each of the E. coli O26, O111, and O157 strains containing both the stx1 and stx2 genes were grown in the absence or presence of these agents at 1/4 minimal inhibitory concentration for 6 h, 12 h, and 18 h. At the concentrations used in this study, none of the agents significantly altered cell count compared with the control group. The level of cytotoxicity in the imipenem group was lower at 12 hand 18 h than their respective controls. In contrast, the level of cytotoxicity in cultures treated with trimethoprim/sulfamethoxazole, norfloxacin, and amikacin was increased. The strains were also examined for the release of Shiga toxins 1 and 2 following treatment with the agents, which were measured by the reversed passive latex agglutination (RPLA) method. The RPLA assay showed a suppression of release of Shiga toxin 2 in the strain cultures containing imipenem. These results indicate that imipenem may be a safe and effective agent for inhibition of these bacteria, which has clinical implications for the treatment of EHEC infections.

• Food Science of Animal Resources
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• v.40 no.6
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• pp.938-945
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• 2020

A dynamic model was developed to predict the Escherichia coli cell counts in pig trotters at changing temperatures. Five-strain mixture of pathogenic E. coli at 4 Log CFU/g were inoculated to cooked pig trotter samples. The samples were stored at 10℃, 20℃, and 25℃. The cell count data was analyzed with the Baranyi model to compute the maximum specific growth rate (μ_max) (Log CFU/g/h) and lag phase duration (LPD) (h). The kinetic parameters were analyzed using a polynomial equation, and a dynamic model was developed using the kinetic models. The model performance was evaluated using the accuracy factor (A_f), bias factor (B_f), and root mean square error (RMSE). E. coli cell counts increased (p<0.05) in pig trotter samples at all storage temperatures (10℃-25℃). LPD decreased (p<0.05) and μ_max increased (p<0.05) as storage temperature increased. In addition, the value of h₀ was similar at 10℃ and 20℃, implying that the physiological state was similar between 10℃ and 20℃. The secondary models used were appropriate to evaluate the effect of storage temperature on LPD and μ_max. The developed kinetic models showed good performance with RMSE of 0.618, B_f of 1.02, and A_f of 1.08. Also, performance of the dynamic model was appropriate. Thus, the developed dynamic model in this study can be applied to describe the kinetic behavior of E. coli in cooked pig trotters during storage.

• Journal of Animal Science and Technology
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• v.51 no.4
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• pp.321-328
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• 2009

A total of fourteen, 1-wk-old male Holstein calves were allotted into two groups consisted of control (CON) and IGY which was orally administrated with immunoglobulin yolk (IgY) for 1wk. Calves in both groups were provided with milk replacer according to feeding program and had ad libitum access to timothy hay for the entire experimental period (7wks). At 0, 7 and 49 day of experiment, blood samples were collected from the jugular vein of calves to investigate blood biochemical profiles and the differential count (%) of white blood cell (WBC). We also monitored growth performance and colony forming unit (CFU) of fecal microbial population in calves. The adminstration of IgY in calves did not affect body weight and weight gain during 49 days feeding trial compared with control group. The CFU of E. coli and Lactobacilli in the feces of calves were not significantly affected by IgY treatment, whereas the score of the calf scours during day 43 to 49 in IgY group showed a significant (P<0.05) solid type. There were no differences in plasma biochemical components including total protein, albumin, immunoglobulin and the other indicators. As for WBC differential count (%), there was no statistical difference in the percentages of neutrophil, lymphocyte, monocyte, eosinophil and basophil at 0, 7 and 49 days after the oral supplementation of IgY. In conclusion, the oral supplementation of IgY as an immunostimulant did not affect growth performance, fecal microbial population, blood biochemical profile and WBC differential count in Holstein calves.

• Journal of environmental and Sanitary engineering
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• v.5 no.1
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• pp.65-72
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• 1990

To study on the water quality of domestic purifier, twenty four samples of clean water by purifier and the raw water(tap water) were tested for biological and physico-chemical examination and were checked for style of purification and the period elapsed after changing of purification medium. The results were as follows; Biological and physico-chemical findings of raw water were not exceeded standard values. Average number of general bacteria,2.coli and pH in clean water were significantly higher than that of raw water(respectively, p<0.01), but mean contents of turbidity, chloride, nitrate and iron in clean water were significantly lower than that of raw water(respectively, p<0.01). In general count of bacteria and E.coli, a half of the clean water of ceramic filter and roverse osmosis style were exceeded standard values for drinking water. All of the pH of the ion exchange style clean water were exceeded standard values. But other findings were within standard values. In average bacterial counts and physico-chemical findings of clean water by purification style of purifier, clean water of ion exchange style purifier were lowest number of general bacteria and not detected in 2. coli. But other items were highest. The longer period elapsed after changing of purification medium were the higher contents of biological and physico-chemical findings of clean water.

• Korean Journal of Veterinary Service
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• v.36 no.3
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• pp.203-208
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• 2013

This survey was conducted to evaluate the microbial contamination level of butcher's shops in Seoul, Korea. For microbial inspections, a total of 584 samples (146 cotton work gloves, 146 utensils and equipments, 154 beef samples, 138 pork samples) were collected from butcher's shops. E. coli and pathogenic bacteria such as Staphylococcus aureus, Yersinia enterocolitica, Listeria monocytogenes, Salmonella spp., and E. coli O157:H7 were tested in the samples. As a result, the level of aerobic plate count (APC) ranged ${\leq}10^4\;CFU/cm^2$ from utensils and equipments, $10^1{\sim}10^9$ CFU/glove from cotton work gloves and ${\leq}10^6$ CFU/g from meat. The APC level of E. coli ranged ${\leq}10^1\;CFU/cm^2$ from utensils and equipments, ${\leq}10^5$ CFU/glove from cotton work gloves, and ${\leq}10^3$ CFU/g from meat, respectively. Staphylococcus aureus was detected in 2 beef samples, 1 pork sample, and 10 used cotton work gloves. Yersinia enterocolitica was detected in 3 beef samples, 1 pork sample, and 3 used cotton work gloves. Listeria monocytogenes was detected in 2 used cotton work gloves. In order to improve the sanitation status of butcher's shops, application of HACCP (Hazard Analysis Critical Control Point) or SSOP (Sanitation Standard Operating Procedure), regular hygiene education, and continuous monitoring for microorganisms will be required.

• Childhood Kidney Diseases
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• v.23 no.1
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• pp.22-28
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• 2019

Purpose: We studied the pathogens and trends in antibiotic sensitivity pattern in children with urinary tract infection (UTI) over 8 years in order to evaluate adequate treatment. Methods: We performed a retrospective review of medical records of children with UTI from January 2009 to December 2016 in Daegu Fatima Hospital. Uropathogens and antibiotic sensitivity patterns were selected. Only 1 bacterial species with a colony count of ${\geq}105CFU/mL$ was considered a positive result. We compared 2 periods group (A: 2009~2012, B: 2013~2016) to investigate trends of antibiotic sensitivity pattern. Results: During the 8 year period, 589 cases are identified (E. coli was cultured in 509 cases, 86.4%). Among all patients, this study investigated the antibiotic sensitivity of E. coli. Antimicrobial susceptibility to ampicillin was steadily low for both periods (A: 32.6%, B: 40.1%, P=0.125), and to amikacin was consistently high for both periods (A: 99.4%, B: 99.3%, P=1.000). Antibiotic sensitivity to third-generation cephalosporin decreased from period A to B (A: 91.7%, B: 75.5%, P=0.000). Antibiotic sensitivity to quinolone significantly decreased from A to B (A: 88.4%, B: 78.2%, P=0.003). The prevalence of extended-spectrum ${\beta}$-lactamase-producing E. coli increased from period A to B (A: 6.1%, B: 17.1%, P=0.000). Conclusion: This study showed that conventional antibiotic therapy for the treatment of pediatric UTI needs to be reevaluated. A careful choice of antibiotic is required due to the change in antibiotic sensitivity and the emergence of antibiotic-resistant bacteria.