• Asian-Australasian Journal of Animal Sciences
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• v.17 no.12
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• pp.1746-1750
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• 2004

The PBM ${BioSign}^{TM}$ Salmonella (PBMS) test kit based on an mmunochromatographic method was evaluated for the screening of Salmonella spp. in pure cultures, and 80, 15, and 10 artificially and naturally contaminated, and negative controlled food samples, respectively. The PBMS test involves presumptive qualitative procedures, detecting the presence of Salmonella spp. in foods within 26 h total testing period and allowing the user to release negative products 70 h earlier than the conventional methods. The PBMS test using Buffered Peptone Water and Rappaport-Vassiliadis broth was evaluated for 10 different food types for various Salmonella spp. It showed detection limits of 1 to 25 colony forming units (CFU)/25 g. No cross-reaction was observed, particularly to other gramnegative bacteria. These results indicate the PBMS test is a rapid and inexpensive procedure for the screening of Salmonella spp. present at low concentrations (1 to 25 CFU/25 g) in foods.

• Journal of Microbiology
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• v.43 no.2
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• pp.133-143
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• 2005

Shigellosis is a global human health problem. Four species of Shigella i.e. S. dysenteriae, S. flexneri, S. boydii and S. sonnei are able to cause the disease. These species are subdivided into serotypes on the basis of O-specific polysaccharide of the LPS. Shigella dysenteriae type 1 produces severe disease and may be associated with life-threatening complications. The symptoms of shigellosis include diarrhoea and/or dysentery with frequent mucoid bloody stools, abdominal cramps and tenesmus. Shigella spp. cause dysentery by invading the colonic mucosa. Shigella bacteria multiply within colonic epithelial cells, cause cell death and spread laterally to infect and kill adjacent epithelial cells, causing mucosal ulceration, inflammation and bleeding. Transmission usually occurs via contaminated food and water or through person-to-person contact. Laboratory diagnosis is made by culturing the stool samples using selective/differential agar media. Shigella spp. are highly fragile organism and considerable care must be exercised in collecting faecal specimens, transporting them to the laboratories and in using appropriate media for isolation. Antimicrobial agents are the mainstay of therapy of all cases of shigellosis. Due to the global emergence of drug resistance, the choice of antimicrobial agents for treating shigellosis is limited. Although single dose of norfloxacin and ciprofloxacin has been shown to be effective, they are currently less effective against S. dysenteriae type 1 infection. Newer quinolones, cephalosporin derivatives, and azithromycin are the drug of choice. However, fluoroquinolone-resistant S. dysenteriae type 1 infection have been reported. Currently, no vaccines against Shigella infection exist. Both live and subunit parenteral vaccine candidates are under development. Because immunity to Shigella is serotype-specific, the priority is to develop vaccine against S. dysenteriae type 1 and S. flexneri type 2a. Shigella species are important pathogens responsible for diarrhoeal diseases and dysentery occurring all over the world. The morbidity and mortality due to shigellosis are especially high among children in developing countries. A recent review of literature (KotIoff et al.,1999) concluded that, of the estimated 165 million cases of Shigella diarrhoea that occur annually, $99\%$ occur in developing countries, and in developing countries $69\%$ of episodes occur in children under five years of age. Moreover, of the ca.1.1 million deaths attributed to Shigella infections in developing countries, $60\%$ of deaths occur in the under-five age group. Travellers from developed to developing regions and soldiers serving under field conditions are also at an increased risk to develop shigellosis.

• Economic and Environmental Geology
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• v.32 no.2
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• pp.177-187
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• 1999

Gravity, magnetic and VLF surveys were conducted to investigat the structural stability and hazards associated with the Ubong landfill in Pohang City, which has been built to dump industrial wastes. In 1994, the collapse of a bank happened in the 6th landfill site due to sudden heavy rain, and a large quantity of waste materials flowed out to the nearby landfill sites, factories and roads. We used $10{\times}10m$ resolution DEM data for gravity reductions. The maximum variation of the terrain effect in the survey area is about 0.5 mgal and the terrain effect is large in the vicinity of bank boundary. The Bouguer gravity anomaly map shows the effect due to the variatino of thickness and type of waste materials. The small negative gravity anomaly increases from the 9th site to the 6th site. The small negative gravity anomaly of the 9th site reflects the relatively shallow dumping depth of average 14.5 m in this site and increased density of waste materials by the repeated stabilization process of soil overlaying. The 6th site is located at the center of the former valley and rainfall and groundwater are expected to flow from south-east to north-west. Therefore, considering the previous accident of mixing waste and bank materials at the north-west boundary of the landfill, there may be some environmental problems of leakage of contaminated water and bank stability. The complex inversion technique using Simulated annealing and Marquardt-Levenberg methods was applied to calculate three-dimensional density distribution from gravity data. In the case of 6th site, it is apparent that the landfill had been dumped in four sectors. However, most part of the 9th site and showed that high magnetic industrial wastes were concentrated in the 6th site. The result of magnetic survey showing low magnetic anomalies along the boundaries of two sites is similar to that of gravity data. The VLF data also reveals four divided sectors in the 6th site, and overall anomaly trend indicates the directio of former valley.

• Economic and Environmental Geology
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• v.29 no.1
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• pp.87-103
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• 1996

The purposes of this research are to investigate the pollution level of heavy metals due to the urbanization and industrialization in the satellite cities of Seoul, and to assess the chemical species and the sources of heavy metals in highly contaminated soils and dusts. Soil and dust samples were collected from the Uijeongbu and the Koyang cities, which are northern and the northwestern satellite cities of Seoul metropolitan city, respectively. Relatively high pH values($6.3{\sim}9.9$) were found in roadside soils compared with agricultural and forest soils. Difference in pH values of soils was not identified between before and after rainy seasons. In spite of no specific pollution sources in the above cities, the contents of Cu, Pb, and Zn in soils and dusts were much higher than the world average contents. The metal levels in dusts were higher than those in soils, but the metal concentration in dusts was significantly decreased after rainy season. Pollution index was high(> 1.0) in the areas of heavy traffic, industrial complex, and city centres. There is an appreciable proportion of total Zn in exchangeable/water-acid soluble fraction. Copper is predominantly associated with reducible and oxidizable phases, whereas Pb is largely in reducible association. It is concluded that the mobility and bioavailability of metals are high in the order of Zn >> Cu > Pb, on the basis of characteristic particle morphology and chemical composition, Pb-containing particles are originated probably from the automobile exhaust, particularly in heavy traffic areas. The metallic forms and iron-oxide associated forms of Cr, Ni, Cu, Zn, and Pb can be assessed as industrial origin.

• Journal of Plant Biotechnology
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• v.30 no.1
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• pp.103-108
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• 2003

LinA gene involving in the ${\gamma}$-benzenehexachloride degradation have been cloned from Sphingmonas paucimobilis UT26. This linA gene which catalyzes the first dechlorination step of ${\gamma}$-benzenehexachloride is known to play a key role in the ${\gamma}$-benzenehexachloride degradation pathway in UT26. In this study, the linA gene was designed to clean-up the ${\gamma}$-benzenehexachloride and its derivatives contaminated in soil, water and air using transgenic tobacco plants. The linA transgene was introduced into the chromosome of tobacco using leaf-disk transformation approach as revealed by Southern blot analysis. In addition, mRNA and protein produced by linA gene was expressed at a high level in the leaf tissue as demonstrated by both northern blot analysis and Western bolt analysis with polyclonal antibody against S. paucimobilis UT26. in vitro analysis using GC-MS showed that transgenic tobacco plant produced the linA protein which effectively degraded ${\gamma}$-benzenehexachloride into ${\gamma}$- pentachlorocyclohexene and 1,2,4-trichlobenzene compounds which are less toxic.

• Journal of Preventive Medicine and Public Health
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• v.33 no.1
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• pp.10-16
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• 2000

Objectives : This study was carried out to investigate the sources of infection and modes of transmission of an outbreak of shigellosis that occurred among students of B middle and high school in Bonghwa, Korea from May 1 to 21, 1999. Methods : We conducted questionnaires to 468 students, 38 stalls and 9 food handlers twice times (May 6, May 21) for follow up and secondary attack rate. Personal details and history of illness and exposure to particular foods were sought. And we conducted rectal swab for culture to 243 students, 33 staffs and 9 food handlers. Bacteriological examinations of water in the school were done. Cases were identified as subjects who had diarrhea (two or more loose stools in a 24-hour periods) on or after May 1. Results : A total of 307 cases (attack rate: 59.6%) of 515 subject were identified, including 50 confirmed (46 students and 4 staffs) by S. sonnei. All 9 food handlers denied illness and were had rectal swab for culture at May 6 that were negative for S. sonnei. 146 of 307 reported fever, 156 had tenesmus, 44 reported vomiting, and only 5 of 307 reported blood in the stool. The median duration of diarrhea was 4 days (range: 1-18 days). The mean incubation period until onset of diarrhea was 63 hours (range: 46-144 hours) and the secondary attack rate was 2.8% (43 cases of 1,561 family members). Risk for illness was higher among students who had eaten watered kimchi at March 30 than among those who did not [301(72.7%) of 417 versus 5(9.6%) of 52; RR=7.51;95% CI=3.26-17.31]. Conclusion : The source of infection was estimated to be contaminated watered kimchi by ore or two food hardier who is presumed to be carrier.

• Journal of the Korean Society of Clothing and Textiles
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• v.39 no.2
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• pp.287-293
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• 2015

This research verifies stainability, super bacteria antibacterial features and antibiotic resistance of Ulmus davidiana var. japonica Nakai (UD) extract in dye cotton cloth. UD was extracted with hot water, the test cloth dyed, and then processed by mordanting treatment using $FeSO_4$ $7H_2O$, $CuSO_4$ $5H_2O$ and $Al_2(SO_4)_3$. The surface color and color fastness of the three kinds (original cloth, the cloth without mordancy and mordant cloth) were measured and the influence of dying of cotton cloth and the mordant method on the genesistasis of Methicillin-resistant Staphylococcus aureus (MRSA), antibiotic resistant bacteria. 1. The surface color of the cotton cloth for dyeing (without and with mordancy) displayed a reddish and yellowish color. Stainability was greatest when the mordant of $FeSO_4$ $7H_2O$ was used. 2. When a mordant was not used for dyeing, the color fastness to washing, perspiration and friction of the contaminated cloth was satisfactory at 4 to 5 grade in general. 3. As for the antibiotic effect to super bacteria, the growth of germ was meaningfully suppressed both on the cloth without and with mordancy compared to the comparison cloth; in addition, the dyeing method with the biggest antibacterial impact was found to be the mordancy with the mordant of $CuSO_4$ $5H_2O$ after dyeing. The results of the experiments that involved dyeing with UD extract showed that cotton cloth processed through mordancy with the mordant of $CuSO_4$ $5H_2O$ had the biggest antibiosis to super bacteria and that processed with the mordant of $FeSO_4$ $7H_2O$ had the greatest stainability.

• Korean Journal of Environmental Agriculture
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• v.17 no.1
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• pp.59-64
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• 1998

The environmental problem of the rural area has been accelerated in soil as well as water. Soil contamination is usually caused by improper operation of landfills, abandoned mine fields, accidental spills, and illegal dumpings. Once soil contamination is initiated, pollutants migrate and may cause groundwater contamination which takes much effort for remediation. Early detection, therefore, is important to prevent further contamination. Electrical resistivity method was used to detect soil contamination, but it was not effective to the heterogeneous condition. Static cone penetrometer test (CPT) has been used widely to investigate geotechnical properties of the underground. In this study, electrical resistivity method and CPT are combined to improve the applicability of it. The pilot test was performed to examine the variation of electrical resistivity with different soil minerals and pore fluid characteristics. Soil samples used were poorly graded sand, silty sandy soil, and weathered granite soil. For all the cases, electrical resistivity decreased with increasing of moisture content. Soil mineral also affected the electrical resistivity significantly. Above all, leachate addition in the pore fluid was very sensitive and caused decreasing of electrical resistivity markedly. It implies that electrical resistivity method can be applied to investigate pollutant plume effectively. This is specially sure when the sensors contact the contaminated soils directly. The CPT method involves cone penetration to the ground, therefore, underground contamination around the cone could be investigated effectively even for heterogeneous condition as it penetrates if electrical resistivity sensors are attached on the cone.

• Korean Journal of Environmental Agriculture
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• v.31 no.1
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• pp.75-95
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• 2012

BACKGROUND: Increase of heavy metals in agricultural ecosystem has become a social issue nationwide as it is related to public health. This review was performed to find out more systematic and integrated future researches on heavy metals using up to date articles published in the Korean journals related to agricultural environment. METHODS AND RESULTS: Researches on heavy metals in agricultural soils and plant uptake were categorized by the establishment of criteria, analytical methods, monitoring, management of source, characteristics and behavior in soil, plant uptake, bioavailability affecting physico -chemical properties in soil, risk assessment and soil remediation. In the early 1990s, the monitoring for heavy metals in soil has been widely performed. Accumulation of heavy metals in contaminated soil and availability to plants has also attracted interests to study the soil remediation using various physico-chemical methods. The phytoavailability and phytotoxicity of heavy metals have been mainly studied to assess the safety of agro-products using risk assessment techniques in the 2000s. CONCLUSION: Future direction of research on heavy metal in agricultural environment must be carried out by ensuring food safety and sustainability. A steady survey and proper management for polluted regions should be continued. Law and regulation must be modified systematically. Furthermore, studies should expand on mitigation of heavy metal uptake by crops and remediation of polluted fields.

• Korean Journal of Food Science and Technology
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• v.35 no.3
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• pp.470-474
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• 2003

DNA sequence information on small-subunit rRNA gene (16S rDNA) obtained from food-poisoning bacterial culture was used to investigate the presence of bacterial pathogens in food. By reverse dot blot detection method, presence of food-poisoning bacteria could be confirmed on hybridization of digoxigenin-labeled 16S rDNA Polymerase Chain Reaction (PCR) primer product and biotin-labeled specific oligonucleotide probe. Escherichia coli, Bacillus cereus. and Salmonella sp. were used as the representative food-poisoning bacterial microorganisms. An oligonucleotide probe, based on the variable region of 16S rRNA gene, was used as the specific probe. These tools may be more useful than classic biochemical method for rapid identification of contaminated food.