• Journal of Food Hygiene and Safety
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• v.13 no.2
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• pp.112-120
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• 1998

This study was performed to investigate the synergistic effect of chitosan and sorbic acid as a new food preservative. So it was performed to investigate inhibitory effect on growh of E. coli 0157:H7, gram negative pathogenic food borne disease bacteria and of S. aureus, gram positive food borne disease bacteria in chitosan, sorbic acid and combination of chitosan and sorbic acid. Minimun Inhibitory Concentration (MIC) of chitosan in E. coli 0157:H7 was 500 ppm at pH 5.0, 250 ppm at pH 5.5, 500 ppm at pH 6.0, and 2000 ppm at pH 6.5, while in Staph. aureus 31.25 ppm at pH 5.0 and 62. 5 ppm at more than pH 5.5. also, MIC of sorbic acid in E. coli 0157:H7 was 500 ppm at pH 5.0, 1500 ppm at pH 5.5, and 2000 ppm at more than pH 6.0, while in Staph. aureus 1500 ppm at pH 5.0 and more than 2000 ppm at more than pH 5.5. Due to the effect of pH in E. coli 0157:H7, MIC of combined chitosan and sorbic acid was 500 ppm of chitosan with 500 ppm of sorbic acid at pH 6.5, but 250 ppm of chitosan with 31.3 ppm of sorbic acid at pH 5.0. In Staph. aureus, there was great effect of chitosan, but neither effect of pH nor sorbic acid. When E. coli 0157:H7 were treated with 500 ppm of chitosan with 500 ppm of sorbic acid and 250 ppm of chitosan with 250 ppm of sorbic acid at pH 6.5, they were inhibited. But, they were increased at the initial concentration of bacteria at 1000 ppm of chitosan in 18 hours, at 500 ppm of chitosan in 36 hours. There was no effect of growth inhibition with sorbic acid but great effect with chitosan on Staph. aureus. The correl~tions between MICs of chitosan and sorbic acid in E. coli 0157:H7 accoding to pH were higher than those in Staph. aureus. R values in E. coli 0157:H7 were 0.95 (p<0.01), 0.99 (p<0.01), 0.97 (p<0.01), and 0.99 (p<0.01) at pH 6.5, 6.0, 5.5, and 5.0 respectively. The synergistic effect of chitosan and sorbic acid in E. coli 0157:H7 could be confirmed from the result of this experiment. Therefore, it was expected that the food preservation would increase or maintain by using sorble acid together with chitosan, natural food additive that did no harm to human body.

• Parasites, Hosts and Diseases
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• v.51 no.6
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• pp.677-681
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• 2013

Paragonimiasis is an important food-borne parasitic zoonosis caused by infection with lung flukes of the genus Paragonimus. Of the 7 members of the genus known in Thailand until recently, only P. heterotremus has been confirmed as causing human disease. An 8th species, P. pseudoheterotremus, has recently been proposed from Thailand, and has been found in humans. Molecular data place this species as a sister species to P. heterotremus, and it is likely that P. pseudoheterotremus is not specifically distinct from P. heterotremus. In this study, we collected metacercariae of both nominal species (identification based on metacercarial morphology) from freshwater crabs from Phetchabun Province in northern Thailand, Saraburi Province in central Thailand, and Surat Thani Province in southern Thailand. In addition, we purchased freshwater crabs imported from Myanmar at Myawaddy Province, western Thailand, close to the Myanmar-Thailand border. The DNAs extracted from excysted metacercariae were PCR-amplified and sequenced for ITS2 and cox1 genes. The ITS2 sequences were nearly identical among all samples (99-100%). Phylogenies inferred from all available partial cox1 sequences contained several clusters. Sequences from Indian P. heterotremus formed a sister group to sequences from P. pseudoheterotremus-type metacercariae. Sequences of P. heterotremus from Thailand, Vietnam, and China formed a separate distinct clade. One metacercaria from Phitsanulok Province was distinct from all others. There is clearly considerable genetic variation in the P. heterotremus complex in Thailand and the form referred to as P. pseudoheterotremus is widely distributed in Thailand and the Thai-Myanmar border region.

• Korean Journal of Veterinary Research
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• v.51 no.1
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• pp.21-28
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• 2011

Salmonella Enteritidis (SE) has been a major causative agent of food-borne human disease due to consumption of contaminated eggs and poultry meat. To prevent SE infection in poultry, and therefore minimize human infections, vaccination with either killed or live SE vaccine is suggested. We evaluated a newly developed killed bacterin using a representative SE isolate in Korea. Among pool of SE isolates, two highly virulent isolates (the one isolate from chicken, the other from human) were selected by measuring mortality in mouse and chickens administered. The chickens were injected intramuscularly with killed vaccine and were challenged with highly virulent SE strain 3 week after vaccination. The recovered colony count (cfu/g) of spleen and cecal content in the vaccinated groups was reduced compared with those of the unvaccinated control group. The antibody level in the vaccinated groups was higher at 3 week post vaccination. These results indicate that vaccination with killed vaccine was effective in preventing the infection of virulent SE. Further study for a large number of layers should be needed for the effect of egg production, SE shedding in feces, persistence of antibody level.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.51 no.5
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• pp.535-541
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• 2018

This study evaluated the sanitary state of seawater and shellfish in Yongnam-Gwangdo area from January 2014 to December 2016. The sampling stations for sanitary survey in Yongnam-Gwangdo area were composed of 41 seawater stations and 5 oyster Crassostrea gigas stations. The samples were collected monthly at each station. Shellfish-borne disease is associated with bacteria and viruses in the presence of fecal coliforms. Bacteriological pollution levels of shellfish increase with seawater quality. Therefore, fecal coliforms are very important criteria for evaluating the safety of fisheries in coastal areas. The geometric mean and the estimated 90th percentile ranges of total and fecal coliforms for seawater were 1.8-11.7, 2.8-233.6, <1.8-6.7 and 1.8-100.2 MPN/100 mL, respectively. The range of E. coli levels for oysters was <20-1,300 MPN/100 g. Based on various standards, the sanitary condition in Yongnam-Gwangdo area was evaluated as follows: clean area (Korean criteria), conditionally approved area (US criteria) and class B (EU criteria).

• Parasites, Hosts and Diseases
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• v.53 no.5
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• pp.641-645
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• 2015

Fascioliasis, a food-borne trematode zoonosis, is a disease primarily in cattle and sheep and occasionally in humans. Water dropwort (Oenanthe javanica), an aquatic perennial herb, is a common second intermediate host of Fasciola, and the fresh stems and leaves are widely used as a seasoning in the Korean diet. However, no information regarding Fasciola species contamination in water dropwort is available. Here, we collected 500 samples of water dropwort in 3 areas in Korea during February and March 2015, and the water dropwort contamination of Fasciola species was monitored by DNA sequencing analysis of the Fasciola hepatica and Fasciola gigantica specific mitochondrial cytochrome c oxidase subunit 1 (cox1) and nuclear ribosomal internal transcribed spacer 2 (ITS-2). Among the 500 samples assessed, the presence of F. hepatica cox1 and 1TS-2 markers were detected in 2 samples, and F. hepatica contamination was confirmed by sequencing analysis. The nucleotide sequences of cox1 PCR products from the 2 F. hepatica-contaminated samples were 96.5% identical to the F. hepatica cox1 sequences in GenBank, whereas F. gigantica cox1 sequences were 46.8% similar with the sequence detected from the cox1 positive samples. However, F. gigantica cox1 and ITS-2 markers were not detected by PCR in the 500 samples of water dropwort. Collectively, in this survey of the water dropwort contamination with Fasciola species, very low prevalence of F. hepatica contamination was detected in the samples.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 1997.11a
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• pp.3-31
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• 1997

Water has always played a significant role in the lives of people. In urbanised Rome, with its million people. sophisticated supply systems developed and then fled with the empire. only to be rediscovered later But it was the industrial Revolution commencing in the eighteenth century that ushered in major paradigm shifts In use and altitudes towards water. Rapid and concentrated urbanisation brought problems of expanded demands for drinking supplies, waste management and disease. The strategy of using water from local streams, springs and village wells collapsed under the onslaughts of rising urban demands and pollution due to poor waste disposal practices. Expanding travel (railways. and steamships) aided the spread of disease. In England. public health crises peaks, related to water-borne typhoid and the three major cholera outbreaks occurred in the late eighteenth and early nineteenth century respectively. Technological, engineering and institutional responses were successful in solving the public health problem. it is generally accepted that the putting of water into pipe networks both for a clean drinking supply, as well as using it as a transport medium for removal of human and other wastes, played a significant role in towering death rates due to waterborne diseases such as cholera and typhoid towards the end of the nineteenth century. Today, similar principles apply. A recent World Bank report Indicates that there can be upto 76％ reduction in illness when major water and sanitation improvements occur in developing countries. Water management, technology and thinking in Australia were relatively stable in the twentieth century up to the mid to late 1970s. Groundwater sources were investigated and developed for towns and agriculture. Dams were built, and pipe networks extended both for supply and waste water management. The management paradigms in Australia were essentially extensions of European strategies with the minor adaptions due to climate and hydrogeology. During the 1970s and 1980s in Australia, it was realised increasingly that a knowledge of groundwater and hydrogeological processes were critical to pollution prevention, the development of sound waste management and the problems of salinity. Many millions of dollars have been both saved and generated as a consequence. This is especially in relation to domestic waste management and the disposal of aluminium refinery waste in New South Wales. Major institutional changes in public sector water management are occurring in Australia. Upheveals and change have now reached ail states in Australia with various approaches being followed. Market thinking, corporatisation, privatisation, internationalisation, downsizing and environmental pressures are all playing their role in this paradigm shift. One casualty of this turmoil is the progressive erosion of the public sector skillbase and this may become a serious issue should a public health crisis occur such as a water borne disease. Such crises have arisen over recent times. A complete rethink of the urban water cycle is going on right now in Australia both at the State and Federal level. We are on the threshold of significant change in how we use and manage water, both as a supply and a waste transporter in Urban environments especially. Substantial replacement of the pipe system will be needed in 25 to 30 years time and this will cost billions of dollars. The competition for water between imgation needs and environmental requirements in Australia and overseas will continue to be an issue in rural areas. This will be especially heightened by the rising demand for irrigation produced food as the world's population grows. Rapid urbanisation and industrialisation in the emerging S.E Asian countries are currently producing considerable demands for water management skills and Infrastructure development. This trend e expected to grow. There are also severe water shortages in the Middle East to such an extent that wars may be fought over water issues. Environmental public health crises and shortages will help drive the trends.

• Korean Journal of Veterinary Research
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• v.35 no.2
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• pp.405-416
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• 1995

FBs, secondary metabolites of several species of Fusaria, especially Fusarium moniliforme and F proliferatum, are commonly contaminated in com and other food grains throughout the world. Only recently identified, these mycotoxins have been associated field outbreaks of ELEM in horses and PPE in pigs. Currently, naturally or experimentally induced FB toxicosis has been studied in poultry, ruminants and rabbits. Poultry fed FB showed decreased growth rate, performance, and immune competence, as well as embryopathic, and embryocidal effects, and ricktes. Ruminants seem to be relatively less susceptible to FBs than other doestic animal. FB toxicosis reveals that liver is a target organ in all species, although other organs are affected in a species specific manner. Recently, the main target organs for $FB_1$ toxicity in rabbits was shown to be the kidney. Even low concentrations of FBs are likely to be a problem for animal health. A current study being conducted showed that feed containing low level of $FB_1$ reduces the ability of pulmonary intravascular macrophages in pig to clear blood-borne particles which would increase the susceptibility of animals to bacterial disease. The mechanism of FB toxicity remains unknown, but may be related to altered sphingolipid biosynthesis by inhibiting sphinganine N-acyltransferase. Elevations of serum and tissue SA:SO ratio have been observed in horse, pig, chicken, turkey, and rabbit, which could could serve as in effective biomarker for consumption of FB-containing feeds. There is limited information detailing dose-effect relationships either from field cases or in the laboratory. More research on the factors, including the prevalence and tolerance levels of FBs in feedstuffs that cause domestic animal disease associated with FBs, is urgently needed.

• Journal of Food Hygiene and Safety
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• v.23 no.1
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• pp.40-50
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• 2008

Spread of pathogenic micro-organisms through contaminated hands is a well recognized way of transmitting disease such as food poisoning. We investigated the prevalence of aerobic plate counts, coliform bacteria, and food-poisoning bacteria on hands in various age groups. The average number of aerobic plate counts was 3.3 log CFU/hand in kindergarteners, 3.4 log CFU/hand in elementary students, 3.2 log CFU/hand in middle school students, 3.4 log CFU/hand in high school students, and 3.3 log CFU/hand in adults. Two kindergarteners, 6 elementary students, and 2 adults were positive for the coliform bacteria. Among the food poisoning bacteria we tested, S. aureus was isolated from 47 individuals. Eight isolates of B cereus were all from kindergarteners. C. perfringens was isolated from 7 individuals. Among 47 isolates of S. aureus, 25 isolates produced toxins. Seven of eight isolates of B. cereus produced toxins. None of seven C. peifringens isolates produced toxins. All 47 isolates of S. aureus were sensitive to ciprofloxacin, trimethoprim/sulfamethoxazole, clindamyccin, imipenem, rifampin and vancomycin. Four isolates (8.5%) were resistant to cefepime, chloramphenicol, cefotetan, and gentamycin. Five isolates (10.6%) were resistant to oxacillin and 6 isolates were resistant to tetracycline. This study shows that it is needs to be established policy of school lunch and personal sanitation management.

• Microbiology and Biotechnology Letters
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• v.41 no.3
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• pp.311-319
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• 2013

In an effort to characterize the physicochemical properties and microbial risks associated with the soy sauce jangachi (Korean traditional pickle), 15 different home-made products, which were prepared from medicinal plants and wild edible vegetables, from head-families of Andong, Kyungsangbuk-do Province in Korea, and 6 different commercial products sold at supermarket, were investigated. The average pH of the mature soaking solutions and plants soaked in the 21 jangachi were $3.99{\pm}0.38$ and $3.51{\pm}0.41$, and the average acidity of the mature soaking solutions and soaked plants were $1.59{\pm}0.54$ and $1.65{\pm}0.76$, respectively. The average brix of the mature soaking solutions and plants soaked were $27.67{\pm}8.38$ and $25.61{\pm}6.60$, respectively. In salinity, which is a major factor in jangachi industry production, the average salinity of the mature soaking solutions and soaked plants were $7.55{\pm}3.26$ and $5.75{\pm}2.23$, respectively. In particular, the hot-peppers, eusuri, du-rup, kaet-ip, kuji-ppong, myeng-i and sancho jangachi were amongst the home-made products, and the salinity was above 8.8%, which was 2 folds-higher than that of the commercial sterilized products, and 1/3-lower than commercial non-sterilized products. The color difference and turbidity of jangachi were dependent on the plant parts used. In microbial risk assessment, the microorganisms related with food-borne disease, such as Escherichia coli, Salmonella sp, and Shigella sp., were not detected. After some time, total cell count analysis revealed that the commercial products sold at supermarkets were more vulnerable than the home-made products.

• Food Science of Animal Resources
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• v.28 no.5
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• pp.555-561
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• 2008

Ninety-nine samples of powdered infant formula in a market were collected from the local market and their contaminations for total aerobic bacteria, coliform, FAO/WHO Category A, B, and C pathogens were analyzed. Total aerobic bacteria were detected in 92 of 99 samples (93%) at levels of $1.83{\pm}0.68\;Log\;MPN/g$. These levels were below legal levels specified for infant formulas except for one sample detected by 4.5 Log CFU/g. Coliform was detected in 12 of 99 samples (12%) at levels of $1.26{\pm}1.03\;Log\;MPN/g$ whereas non-detection was required according to the specification of coliform in infant formulas. Escherichia coli was detected in 1 of 99 samples by 0.48 Log MPN/g. Salmonella and Enterobacter sakazakii among Category A weren't detected in all the samples. Enterobacteriaceae, Category B group, were detected in 25 samples of total 99 samples (25%) by $0.83{\pm}1.37\;Log\;MPN/g$. Enterobacteriaceae identified by API 20E were Escherichia vulneris, Es. hermannii, Pantoea spp., Citrobacter koseri, Klebsiella pneumoniae, En. cloaceae. Bacillus cereus among Category C was highly detected in 29 of 99 samples (29%) at levels of $0.69{\pm}0.32\;Log\;MPN/g$ with the most probable number count method, which were below legal levels for the specification of B. cereus in infant formulas. Clostridium perfringens, E. coli O157, Staphyloccus aureus, Listeria monocytogenes, Yersinia enterocolitica, and Campylobacter jejuni/coli were not detected. Contamination level of major pathogens was low and falls within the range of specification of infant formulas. However, Enterobacteriaceae and B.cereus showed the high prevalence and some Enterobacteriaceae causing disease were detected. Therefore, it is necessary to monitor the potential pathogens continually and reduce them to improve the microbial quality of non-sterilized powdered infant formulas.