• Journal of Food Hygiene and Safety
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• v.35 no.1
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• pp.37-44
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• 2020

This study investigated the probability of foodborne illness caused by raw oyster consumption contaminated with high risk Vibrio species such as V. vulnificus and V. cholerae. Eighty-eight raw oyster samples were collected from the south coast, west coast and Seoul areas, and examined for the prevalence of high risk Vibrio species. The growth patterns of V. vulnificus and V. cholerae in raw oysters were evaluated, and consumption frequency and amounts for raw oyster were investigated from a Korean National Health and Nutrition Examination Survey. With the collected data, a risk assessment simulation was conducted to estimate the probability of foodborne illness caused by intake of raw oysters, using @RISK. Of 88 raw oysters, there were no V. vulnificus- or V. cholerae-positive samples. Thus, initial contamination levels of Vibrio species in raw oysters were estimated by the statistical methods developed by Vose and Sanaa, and the estimated value for the both Vibrio spp. was -3.6 Log CFU/g. In raw oyster, cell counts of V. vulnificus and V. cholerae remained unchanged. The incidence of raw oyster consumers was 0.35%, and the appropriate probabilistic distribution for the consumption amounts was the exponential distribution. A risk assessment simulation model was developed with the collected data, and the probability of the foodborne illness caused by the consumption of raw oyster was 9.08×10^-15 for V. vulnificus and 8.16×10^-13 for V. cholerae. Consumption frequency was the first factor, influencing the probability of foodborne illness.

• Journal of Food Hygiene and Safety
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• v.29 no.4
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• pp.305-311
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• 2014

Minimum infective dose (MID) data has been recognized as an important and absolutely needed in quantitative microbiological assessment (QMRA). In this study, we performed a comprehensive literature review and meta-analysis to better quantify this association. The meta-analysis applied a final selection of 82 published papers for total 12 species foodborne disease pathogens (bacteria 9, virus 2, and parasite 1 species) which were identified and classified based on the dose-response models related to QMRA studies from PubMed, ScienceDirect database and internet websites during 1980-2012. The main search keywords used the combination "food", "foodborne disease pathogen", "minimum infective dose", and "quantitative microbiological risk assessment". The appropriate minimum infective dose for B. cereus, C. jejuni, Cl. perfringens, Pathogenic E. coli (EHEC, ETEC, EPEC, EIEC), L. monocytogenes, Salmonella spp., Shigella spp., S. aureus, V. parahaemolyticus, Hepatitis A virus, Noro virus, and C. pavum were $10^5cells/g$ (fi = 0.32), 500 cells/g (fi = 0.57), $10^7cells/g$ (fi = 0.56), 10 cells/g (fi = 0.47) / $10^8cells/g$ (fi = 0.71) / $10^6cells/g$ (fi = 0.70) / $10^6cells/g$ (fi = 0.60), $10^2{\sim}10^3cells/g$ (fi = 0.23), 10 cells/g (fi = 0.30), 100 cells/g (fi = 0.32), $10^5cells/g$ (fi = 0.45), $10^6cells/g$ (fi = 0.64), $10{\sim}10^2particles/g$ (fi = 0.33), 10 particles/g (fi = 0.71), and $10{\sim}10^2oocyst/g$ (fi = 0.33), respectively. Therefore, these results provide the preliminary data necessary for the development of foodborne pathogens QMRA.

• Journal of Food Hygiene and Safety
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• v.29 no.4
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• pp.299-304
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• 2014

The dose-response models are important for the quantitative microbiological risk assessment (QMRA) because they would enable prediction of infection risk to humans from foodborne pathogens. In this study, we performed a comprehensive literature review and meta-analysis to better quantify this association. The meta-analysis applied a final selection of 193 published papers for total 43 species foodborne disease pathogens (bacteria 26, virus 9, and parasite 8 species) which were identified and classified based on the dose-response models related to QMRA studies from PubMed, ScienceDirect database and internet websites during 1980-2012. The main search keywords used the combination "food", "foodborne disease pathogen", "dose-response model", and "quantitative microbiological risk assessment". The appropriate dose-response models for Campylobacter jejuni, pathogenic E. coli O157:H7 (EHEC / EPEC / ETEC), Listeria monocytogenes, Salmonella spp., Shigella spp., Staphylococcus aureus, Vibrio parahaemolyticus, Vibrio cholera, Rota virus, and Cryptosporidium pavum were beta-poisson (${\alpha}=0.15$, ${\beta}=7.59$, fi = 0.72), beta-poisson (${\alpha}=0.49$, ${\beta}=1.81{\times}10^5$, fi = 0.67) / beta-poisson (${\alpha}=0.22$, ${\beta}=8.70{\times}10^3$, fi = 0.40) / beta-poisson (${\alpha}=0.18$, ${\beta}=8.60{\times}10^7$, fi = 0.60), exponential (r=$1.18{\times}10^{-10}$, fi = 0.14), beta-poisson (${\alpha}=0.11$, ${\beta}=6,097$, fi = 0.09), beta-poisson (${\alpha}=0.21$, ${\beta}=1,120$, fi = 0.15), exponential ($r=7.64{\times}10^{-8}$, fi = 1.00), betapoisson (${\alpha}=0.17$, ${\beta}=1.18{\times}10^5$, fi = 1.00), beta-poisson (${\alpha}=0.25$, ${\beta}=16.2$, fi = 0.57), exponential ($r=1.73{\times}10{-2}$, fi = 1.00), and exponential ($r=1.73{\times}10^{-2}$, fi = 0.17), respectively. Therefore, these results provide the preliminary data necessary for the development of foodborne pathogens QMRA.

• Journal of Animal Environmental Science
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• v.11 no.3
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• pp.189-196
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• 2005

This study was carried out to determine the acceptability of liquid manure bin among livestock farmers and agricultural farmers, and quantify its malodorous compounds. The results were as follows; 1. The size of the manure bins owned by $93\%$ of 60 farmers surveyed was 200 M/T and were all in normal operation. Around $57\%$ of the normally operated bins were processed under aerobic condition. 2. Filly percent of the respondents utilized their liquid manure bin twice a year while $64\%$ used commercial microbial products to enhance maturity of their liquid manure and abatement of malodorous emissions. On the other hand, $43\%$ mentioned problems on the labor requirement, mechanical maintenance and lending cost of liquid manure processing and utilization, and the price of the commercial microbial products. 3. Malodorants emitted from livestock liquid manure bins and their boundary bin depended upon the livestock liquid manure processing condition. Within bin under the aerobic processing condition, Iso-valeric and propionic acid were ranged 0.012 to 0.07ppm and 0.17 to 2.85ppm, respectively. Within bin under the anoxic processing condition, n-butyric, n-valeric acid, and acetaldehyde were ranged 1.5 to 2.3ppm, 1.3 to 1.8ppm, and 0.8 to 2.1ppm, respectively. Malodorants emitted from the boundary of livestock liquid manure bins under the anoxic processing condition were detected the range of 0.4 to 0.9 ppm, more than the concentration of law regulation, as an acetaldehyde, but under the aerobic processing condition, they did not any detection.

• Journal of the Korea Organic Resources Recycling Association
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• v.26 no.3
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• pp.23-31
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• 2018

This study was carried out to investigate the effects of livestock manure compost and fish-meal liquid fertilizer on the growth of cucumber and the soil properties for the stable production of organic cucumber. Cucumber was transplanted in greenhouse on the $6^{th}$ of April in 2017, and this experiment contained five treatments: livestock manure compost 100% (LC 100%), livestock manure compost 50% + fish-meal liquid fertilizer 50% (LC50 + LF50), livestock manure compost 50% (LC50), chemical fertilizer (NPK), and no fertilizer (NF). As a result, it was shown that soil chemical properties of LC50 + LF50 plot is not different from that of LC100 plot except for the EC content, but soil chemical properties of LC50 + LF50 plot is statistically significantly different from that of NPK plot except for pH. As a result of evaluating the functional diversity of soil microbial communities using Biolog system, the substrate richness (S) and the diversity index (H) were the highest in LC50 + LF50 plot. As a result of comparing the cucumber growth and yield, it was found that there was no statistically significant difference between the plant height and the fresh weight of LC100, LC50 + LF50, and NPK plot, but the plant height and the fresh weight of LC100, LC50 + LF50, and NPK plot were different from that of LC50 and NF plot. The yield of cucumber was the highest in NPK plot r(7,397 kg/10a), but there was no statistically significant difference in the yield of cucumber between NPK plot and LC100, LC50 + LF50 plot. The above-described results suggested that the livestock manure compost and fish meal liquid fertilizer can be used for organic cucumber production under greenhouse condition.

• Korean Journal of Food Science and Technology
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• v.39 no.6
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• pp.663-668
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• 2007

This study evaluated the microbial, nutritional, and rheological changes in potatoes, during storage at room, low, and freezing temperatures for 6 months. No significant changes in total aerobic plate counts were observed for any of the samples in the assessment of microbiological quality changes. For the 4 types of frozen potatoes, yeasts and molds were not found until 24 weeks. The sugar contents of the potatoes stored at room and low temperature ($10^{\circ}C$) increased during the first 4 weeks of storage, but then decreased rapidly thereafter; while those in the frozen potatoes did not change significantly throughout the 48 weeks. The vitamin C, B1, and B2 contents of the potatoes stored at room and low temperature had decreased significantly after 4 weeks of storage, however, the levels in the frozen potatoes did not change rapidly. The weight, volume, and hardness of the frozen potatoes changed much less as compared to the potatoes stored at room and low temperature over the 48 weeks of storage. Finally, the cohesiveness of all the samples, except for the frozen mashed potatoes, did not change during storage.

• Journal of dental hygiene science
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• v.13 no.2
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• pp.182-190
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• 2013

Composition of oral microbial flora is suggested to play a role in the maintenance of oral health. Among them, Streptococcus mutans plays an essential role in the formation of dental plaque and it is being noticed as incipient infective bacteria of dental caries. The purpose of this study was to prepare the basic data about distribution of Streptococcus mutans detected from saliva by measuring colony density. It is well known that smoking as well as drinking is a factor of dental caries, however there are few investigations about distribution of Streptococcus mutans either smoking or drinking. The materials of this study were collected from students of dentistry college with general characteristics obtained by self-administered questionnaires. Students were asked to gently chew the paraffin to get saliva for 1 minute. Bacitracin disc in the culture medium was activated for 15 minutes, and then sample was incubated in the activated medium at $37^{\circ}C$ incubator for 48 hours. Streptococcus mutans colonization per 1 ml saliva was measured by the number of criteria. The severe levels of dental caries activity were significantly increased in the case of smoking (from 5.6% to 10%) or drinking (form 0% to 7%), respectively. Also, dental caries activity increased according to smoking and drinking periods longer. However, using the SPSS analytical process (Mann-Whitney's U), no significant differences were observed between the smoking and the non-smoking or the drinking and non-drinking, respectively. These results obtained from dental caries activity of saliva suggest that distribution of Streptococcus mutans following smoking or drinking can be used as a significant information for oral health.

• Journal of Animal Science and Technology
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• v.62 no.5
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• pp.682-691
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• 2020

Careful cleaning and disinfection of pigpens is essential to prevent disease spread and avoid the resultant economic losses. Hygiene in pigpens is generally evaluated by visual monitoring supplemented with bacteriological monitoring, which includes counting the total aerobic bacteria (TAB) and/or fecal indicator bacteria (FIB). However, these methods present drawbacks such as time and labor requirements. As adenosine triphosphate (ATP) is ubiquitous in all living organisms including microorganisms, this study aimed to directly compare the results of microbial assessment and ATP quantification, and to suggest possible detailed application methods of the ATP test for hygiene evaluation in pigpens of a farrowing unit. Before and after standard cleaning procedures, samples were collected from the floor corner, floor center, and feeding trough of four pigpens at different time points. No FIB were detected and both the TAB and ATP levels were significantly decreased in the floor center area after cleaning. FIB were continuously detected after cleaning and disinfection of the floor corners, and there was no significant ATP level reduction. The feeding trough did not show any significant difference in these values before and after cleaning, indicating insufficient cleaning of this area. The levels of TAB and ATP after cleaning were significantly correlated and the average ATP value was significantly lower in the absence of FIB than in their presence. In the absence of standard references, a more thorough hygiene management could be achieved evenly by supplementing cleaning or disinfection based on the lowest ATP results obtained at the cleanest test site, which in the present study was the floor center. Overall, these results indicate that the on-farm ATP test can be used to determine the cleanliness status, in addition to visual inspection, as an alternative to laboratory culture-based testing for the presence of microorganisms.

• Korean Journal of Environmental Biology
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• v.23 no.2 s.58
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• pp.146-151
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• 2005

Recent studies indicated the utility of whole effluent assessment as a measure to control discharge of toxic effluents to receiving water in Korea. However, most studies have been focussed on acute lethal effects of toxic wastewater with little consideration of chronic sublethal impacts which are of growing concern in protecting aquatic ecosystem. We conducted acute and chronic toxicity tests with effluents discharged from five different dyeing plants in Gyeong-gi province using a marine bacterium Vibrio fischeri and a freshwater macroinvertebrate Daphnia magna to demonstrate the importance of assessing chronic sublethal effects. Various levels of acute and chronic toxicities were observed in many samples tested in this study. In 21-d chronic toxicity tests using D. magna all samples showed effects on reproduction and growth. Notable mortalities were also noted in three out of five effluents. The result of the Microtox assay indicated that acute microbial toxicity existed in effluents from two out of five plants and acute daphnid toxicity was observed in only one effluent. The result of this study clearly suggests chronic toxicity tests are more suitable to assess biological effects of effluents because it was shown from this study that even an effluent with no acute toxicity could cause chronically lethal and/or sublethal adverse effects on aquatic biota which may affect the population dynamics in aquatic ecosystem.

• Journal of Conservation Science
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• v.30 no.2
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• pp.169-179
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• 2014

After occurrence of Cyanobacteria in 1997, Songsan-ri tombs located in Gonju have been investigated to monitor for biological damage. The room temperature of Tomb No.6 was $18.6{\sim}19.8^{\circ}C$ and the relative humidity was 94.3~99.9%. The temperature of Royal Tomb of King Muryeong was $17.3{\sim}18.53^{\circ}C$ and the relative humidity was 73.2~96.45%. The variation of relative humidity increased after setting up air vents. If the outside temperature increases, dew condensation occurs on the floor and the north side. When conditioning equipment operates, the maximum temperature differences between walls is $2.8^{\circ}C$. Bacteria from the air of the tomb and on the surface of the walls outnumbered fungi. 20 species of fungi including Alternaria sp., Aspergillus sp., Penicillium sp., and 19 species of bacteria including Pseudomonas sp., Arthrobacter sp., are identified. Microbes in the tombs may damage cultural heritage. The growth possibility of microbes should be estimated because the microbes in the tombs may damage mural painting. The interrelation between microenvironmental condition and biological damage of mural painting should be researched to come up with an long-term conservation method.