• Parasites, Hosts and Diseases
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• v.55 no.5
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• pp.523-532
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• 2017

A field survey studying intestinal parasites in humans and microbial pathogen contamination at environment was performed in a Laotian rural village to identify potential risks for disease outbreaks. A parasitological investigation was conducted in Ban Lak Sip village, Luang Prabang, Lao PDR involving fecal samples from 305 inhabitants as well as water samples taken from 3 sites of the local stream. Water analysis indicated the presence of several enteric pathogens, i.e., Aeromonas spp., Vibrio spp., E. coli H7, E. coli O157: H7, verocytotoxin-producing E. coli (VTEC), Shigella spp., and enteric adenovirus. The level of microbial pathogens contamination was associated with human activity, with greater levels of contamination found at the downstream site compared to the site at the village and upstream, respectively. Regarding intestinal parasites, the prevalence of helminth and protozoan infections were 68.9% and 27.2%, respectively. Eight helminth taxa were identified in fecal samples, i.e., 2 tapeworm species (Taenia sp. and Hymenolepis diminuta), 1 trematode (Opisthorchis sp.), and 5 nematodes (Ascaris lumbricoides, Trichuris trichiura, Strongyloides stercoralis, trichostrongylids, and hookworms). Six species of intestinal protists were identified, i.e., Blastocystis hominis, Cyclospora spp., Endolimax nana, Entamoeba histolytica/E. dispar, Entamoeba coli, and Giardia lamblia. Questionnaires and interviews were also conducted to determine risk factors of infection. These analyses together with a prevailing infection level suggested that most of villagers were exposed to parasites in a similar degree due to limited socio-economic differences and sharing of similar practices. Limited access to effective public health facilities is also a significant contributing factor.

• Korean Journal of Veterinary Research
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• v.39 no.3
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• pp.523-530
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• 1999

Sal enteritidis thin fimbriae, SEF14, were found to be restricted to the predominantly poultry-associated members of the Salmonella serogroup D1 that are considered as the important pathogens in poultry industry. SefA together with sefB and sefC encode the proteins involved in SEF14 biosynthesis. In order to develop the rapid and specific detection methods for Salmonella serogroup D1, a PCR technique for the amplification of sefA gene was established, and its specificity and sensitivity were investigated with various microorganisms. The bacterial genomic DNA was extracted by colony-picking and rapid boiled-lysate technique. In comparison of Sef I and Sef II primers used in the PCR, Sef I primer for sefA gene of 513bp showed higher specificity than that of Sef II. The established PCR was as sensitive as to detect 1pg of Sal enteritidis DNA. When 73 strains in 28 genera including the reference strains and the field isolates of various Salmonella serotypes, Bacillus subtilis, Bordetella bronchisepdca, E coli, Listeria spp., Micrococcus luteus, Rhodococcus equi, Staphylococcus spp., Streptococcus spp., Vibrio parahemolyticus, Yersinia spp. were studied, the established PCR yielded specifically positive results with only Salmonella serogroup D1. The results suggested that the PCR for sefA gene could be a potential candidate among the specific detection methods for Salmonella serogroup D1.

• Food Science and Biotechnology
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• v.17 no.3
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• pp.483-488
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• 2008

Foodborne pathogenic bacteria in various food samples in Korea were monitored and the obtained data was statistically analyzed. A total of 1,240 food samples including 280 sashimi, 244 processed frozen products, 258 kimbab (cooked rice wrapped with seaweed), 337 soybean pastes were obtained from 7 cities including Seoul in Korea. Microorganisms tested were Bacillus cereus, Salmonella spp., Staphylococcus aureus, Escherichia coli, E. coli O157:H7, Vibrio parahaemolyticus, Yersinia enterocolitica, Listeria monocytogenes, Campylobacter jejuni, and Clostridium perfringens. The contaminated microorganisms in food samples were comprised of 10.55% B. cereus, 2.7% S. aureus, 2.0% V. parahaemolyticus, 0.8% C. perfringens, 0.2% Y. enterocolitica, and 0.1% of L. monocytogenes, respectively. Salmonella spp., C. jejuni, and E. coli O157:H7 were not detected in any of the food samples. Particularly, B. cereus that harbors the enterotoxin gene was detected in various foods and regions in Korea, therefore it should be a given special consideration not to allow the hazardous level of contamination.

• Journal of Microbiology
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• v.42 no.3
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• pp.216-222
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• 2004

In a previous paper, the ogdH gene that encodes 2-oxoglutarat dehydrogenase was isolated from Salmonella typhimurium. The catalytic N-terminal region in the enzyme was found to be very specific for the Salmonella species. Therefore, the aim of the present study was to detect S. typhimurium in food sources using primers designed for OGDH-l and OGDH-2 which were based on the salmonella-specific region of the ogdH gene. A simple polymerase chain reaction (PCR) detection method was developed to detect low numbers of S. typhimurium in a chicken meat microbial consortium. Using the ogdH-specific primers under stringent amplification conditions and for gene probe analysis, fewer than 100 colony-forming units (CFUs) were detectable when pure cultures were employed. When the PCR assay was run on S. typhimurium-contaminated meat contents, only the positive meat samples containing as few as 200 CFUs reacted to the assay. The method employed for sample processing is simple and it was determined to provide a sensitive means of detecting trace amounts of S. typhimurium-specific sequences in the presence of mixed meat microbial populations. When compared with six representative intestinal gram-negative bacterial strains in foods, including Vibrio parahaemolyticus, V. vulnificus, Enterobacter cloacae, E. coli O157:H7, Pseudomonas aeruginosa, and Proteus sp., S. typhimurium had a unique and distinct PCR product (796 bp). In conclusion, the two OGDH primers were found to be rapid and sensitive detectors of Salmonella spp for the PCR method.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.45 no.6
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• pp.666-674
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• 2012

We examined the cause of a disease outbreak in adult olive flounder Paralichthys olivaceus, which occurred at a Korean aquaculture farm in Korea in 2011. The principal signs included an expanded abdomen and congested liver, with persistent mortality (a little over two months). At the beginning of the outbreak, farm administrators misjudged the disease as bacterial in origin, because of the aforementioned signs, persistent mortality, and the detection of bacterial species, including Vibrio spp. and Streptococcus spp. Moreover, the detection of viral hemorrhagic septicemia virus (VHSV) by reverse trasnscription-PCR analysis was complicated by use of the VHS-VN primer set, which has been in general use recently, because it produced weak bands in some samples. Therefore, we recommend the use of at least two different primer sets in the diagnosis of VHSV. Our histopathological findings indicate that necrotizing myocarditis could be considered a pathogenic sign of VHSV infection.

• Applied Biological Chemistry
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• v.39 no.4
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• pp.315-319
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• 1996

The yields of methanol extracts of several Chrysanthemum spp.(5 species, 9 parts) and their solvent fractions were investigated. The yields of methanol extracts ranged from 16.9%(for flower of C. indium, Cultivated) to 31.5%(for whole plant of C. indium). In the tests of the antibacterial activity. the methanol extracts from flower of C. zawadskii and C. boreale, whole plant of C. zawadskii, and flower of C. coronarium showed excellent antibacterial activity. Generally, the chloroform fractions exhibited stronger antibacterial activity against all the bacteria tested when compared with other solvent fractions. In case of C. boreale, the chloroform fraction of the whole plant was shown stronger antibacterial activity against all four bacterial strains tested when compared with that of the flower. The chloroform fractions from flower and whole plant of C. boreale and C .zawadskii, and flower of C. coronarium were shown a similar TLC pattern.

• Journal of Environmental Health Sciences
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• v.33 no.3
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• pp.184-189
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• 2007

Pathogenic microbial foodborne disease outbreaks (PMFBDOs) have increased in many countries, the boom in food service establishment is not matched by effective food safety and control. In this study, we investigated the current state and the epidemic aspects of FBDOs in Korea and Japan. In Korea, the average prevalence rate of foodborne disease (FBD) was 15.0 per 100,000 population and cases per outbreak of FBD was 57.0. During the same period in Japan, the prevalence rate showed an average of 24.9, and the cases per outbreak were 16. When both prevalence rate and cases per outbreak were compared, the prevalence rate in Japan was much higher than that in Korea (p<0.01). However, average cases per outbreak of FBD in Japan were much lower than those in Korea (p<0.01). In Korea, outbreaks of FBDs were more common in spring (p<0.01), while in Japan, more frequent in summer and winter (p<0.01). Outbreaks of FBD occurred largely through restaurant and school foods (32.0% and 27.5%) in Korea. In Japan, the proportion of the outbreak cases in the restaurant and home were 23.7% and 12.1%, and cases of unknown causes of FBDs were 48.2%, respectively. Bacteria were the major causes of infection in both countries. The prevalence of PMFBDOs by Salmonella spp. Vibrio parahemolyticus and Staphylococcus aureus were much higher in Korea, while those by Camphylobacter spp. and SRSV were more common in Japan. The causes by virus were more frequent in Japan (13.7%) than in Korea (7.7%). The prevalence of FBDs in Korea and Japan showed characteristic differences, especially in the PMFBDOs due to such factors as geography, climate, culture, diet and food management.

• Journal of Life Science
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• v.11 no.5
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• pp.483-488
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• 2001

The antimicrobial substance produced by Pseudomonas aeruginosa KLP-2 strain was purified and identified. The substance was identified as a pyocyanine by the fast atom bombardment mass(FAB-MS). In physic-chemical properties, the pyocyanine was dark blue needles, and was soluble in various organic solvents such as chlorogorm, methanol, ethanol and ethyl acetae. The pyocyanine possessed a ultraviolet absorbance spectrum in methanol, 0.1 M HCl, and chlorogorm. The maximum absorption peak of the pyocyanine showed at 318 mm in methanol. The molecular formula of the pyocyanine was determined to the $C_{13}$ H$_{10}$ N$_{2}$O and protonate molecular ion species (M+H)$^{+}$ was observed at m/z 211 by FAB-MS. The pyocyanine showed antimicrobial against Bacillus cereus, Bacillus subtilis, Micrococcus luteus, Rodococcus equi, Staphylococcus aureus, Streptococcus faecalis, E. col, Legionella pneumophila, Shigella flexneri Shigella boydii, shgella sonnei, NAG Vibrio cholerae, Vibrio parahaemolyticus, Vibro vulnificus, Yersinia enterocolitica, and Saccharomyces cerevisiae. However, Salmonella spp. Shigela dysenteriae, 3 strains of Pseudomonas aeruginosa, Klebsiela pneumoniae, and Aspergillus niger were resistant to the pyocyanine. The pyocyanine showed the highest antimicrobial activity aganist Legionella pneumophila based on the size of inhibition zone by the disk contained 0.5 $\mu\textrm{g}$ of the pyocyanine.e.

• Journal of Food Hygiene and Safety
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• v.16 no.4
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• pp.280-294
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• 2001

Despite to the reality that the outbreaks from flood poisoning in Korea have been continuously increasing in the last two decades, it was very much neglected even in the public health field in Korea. Food poisoning outbreaks resulted in many cases not only in the damage of health but also in the death of many lives. However, this problem can be effectively solved by effects through health education activities, but not solely by the legal measures. This study was carried out to provide information that can be used in planning health education programs and proposing new rules to prevent any possible outbreaks from flood poisoning. The main problems contributing to flood poisoning outbreaks in an institutional setting or school catering and at home were reviewed and analyzed through the epidemiological investigations and articles related to flood poisoning in the last a decade (1991 ∼ 2000). Accordingly, the data presented in this study are sufficient to show and prove the significant trends in food poisoning accidents in Korea. The major findings investigated in this study are as follows. The frequency of food poisoning accidents as well as the number of victims have continuously increased in Korea. The number of victims per food poisoning accident is also increased from 20 persons in 1990 to 69.8 persons in 2000. Therefore, we should realize that the group poisoning outbreaks occur more frequently and the size of group poisoning accidents is getting larger. Among four seasons, the food poisoning accidents occurred more frequently in the summer (May ∼September) until 1997, However, after 1997, the food poisoning accidents occurred evenly in three seasons except the winter. The most important bacteria that cause food poisoning in Korea were Salmonella spp., Vibrio spp. and Staphylococcus aureus. They occupied 85∼90% of the rates of accidents and the number of victims.

• Fisheries and Aquatic Sciences
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• v.5 no.1
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• pp.43-47
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• 2002

Jeotgal, salt- fermented sea food, is a kind of Korean traditional foods. We carried out hazard analysis on Changran (stomach and intestine of Alaska pollack) Jeotgal and squid Jeotgal through the whole processing procedures at H Co. located at Guryongpo from April 2000 to September 2001. During this studying period, we educated employee regularly and analyzed hazards on the whole process and then could conclude that pathogenic bacteria and metal particles were most important hazards in Jeotgal. Metal particles in end-product will be eliminated by laser detector before packaging. But bacteria must thoroughly manage through the whole process. Bacteriological qualities of the end products were much improved after education for the employees and by effort for HACCP (Hazard Analysis and Critical Control Point) program introduction. Pathogenic bacteria such as pathogenic Escherichia coli, Salmonella spp., coagulase positive Staphylococcus aureus and Vibrio parahaemolyticus were not detected from not only raw materials but also end products. The falling bacteria in the places such as thawing area, packaging area, seasoning area, fermenting room, subsidiary materials room and storage room were less than 30 CFU per plate for 30 minutes during working time. But those were increased more than 10 times during the resting time. It means that special measures are needed during the break time such as lunch time or exchanging working teams.