• Economic and Environmental Geology
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• v.27 no.1
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• pp.101-113
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• 1994

Geochemical investigations based on measurements of water parameters and sampling of stream sediments have been carried out, in the Okdongcheon stream and its tributaries in the Sangdong area of South Korea. There are two main problems occurring in the Okdongcheon stream: an acid mine drainage in the upper reaches and toxic trace metal contamination of the stream sediments mainly in the lower reaches. Acid mine water originating from coal mining was neutralized at the confluence of the Cheonpyongcheon stream whilst suspended solids due to flocculation of iron in water caused turbidity which was undesirable. Sediments in the Okdongcheon stream have been contaminated by mining activites. Iron was heavily concentrated in sediments in the upper Okdongcheon whilst toxic trace metals including Pb, Cu, Zn, Co, Cd, As and Bi were accumulated in sediments at stations draining metallic mining areas and near the tailings dam. There is now a requrement to neutralise the acid mine drainage and to use site-specific analysis of biological communities to ensure the conservation and preservation of aquatic organisms.

• Korean Journal of Animal Reproduction
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• v.16 no.4
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• pp.289-299
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• 1993

The polypeptide patterns of cellular and follicular components were analysed by SDS-PAGE and two dimensional(2-D)electrophoresis combined with isoelectric focusing (IEF) to establish protein profiles in each of the components in porcine follicles. Oocyte-cumulus complexes were cultured in M16+FCS+Gn at 39 in an atmosphere of 5% CO$_2$, in air for 35 h. At the end of the culture, the zona-free oocyte, ZP alone and cumulus cells were prepared and analysed either on 10% SDS-PAGE for the protein profile at the first dimensional gel or 2-D protein pattern. The amounts of each samples were determined for the visualization with Coomasie brilliant blue (CBB) or silver staining, thus giving useful information for the identification of specific proteins in the components or appropriate amount of samples for proper visualization. Oocyte showed 25 and 114 kd major protein band. Other minor components were additionally visualized with CBB on the same gel after silver staining procedure. Cumulus cells also showed specific proteins which is not present in the oocytes. The number of cumulus cell was proper to give major bands with CBB and additional minor bands with silver staining. To establish the degree of contamination from the remnant of the corona radiata to the ZP, zonae were differently prepared or analysed by SDS-PAGE.The preparation of the ZP in this study did not showed any contamination judged by the protein profile of the components. Also follicular fluid showed its specific protein profile without any significant differences among the different sizes of follicles. The established protein profile of each follicular component should be helpful for the identification and elimination of contaminated components, i. e., antigen preparation or immunological studies. The results also suggest that the preparation of each components in the study was appropriate and can be used for a further sensitive biochemical analysis in mammalian oocytes and early embryos.

• Korean Journal of Plant Tissue Culture
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• v.27 no.1
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• pp.7-12
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• 2000

Explants of lettuce (Lactuca sativa L.) were co-cultivated with Agrobacterium tumifacience GV 3101 strain containing nptII gene and cold regulated gene (BN115) from Brassica napus for transformation. Multiple shoots were obtained from the explants in the selection medium (MS basal medium supplemented with 100 mg/L kanamycin, 500 mg/L carbenicillin, 0.1 mg/L NAA, 0.5 mg/L kinetin) after 3 to 4 weeks of co-culture. The putative transgenic shoots were transferred to rooting medium (1/2 MS basal medium supplemented with 100 mg/L kanamycin and 250 mg/L carbenicillin). The selected shoots were tested with PCR analysis using nptll, BN115 primers whether cold-regulated gene was introduced to genome of the plants. The vir G primers were particularly used to check contamination of Agrobacterium during PCR analysis. The nptII and BN115 primers produced the specific PCR bands in the putative transgenic lines but the vir G primers did not. These results confirmed that the PCR products were not the result of contamination with Agrobacterium. Additionally the Southern analysis of the PCR products and RT-PCR analysis proved that the cold-regulated gene was successfully integrated and transcribed in the putative transgenic lettuce plants.

• Journal of Oral Medicine and Pain
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• v.34 no.3
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• pp.237-245
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• 2009

The purpose of this study was to investigate the clinical efficacy of latex cover developed for dental handpiece on contamination of microorganisms during dental treatment and to determine whether it can be an alternative to conventional sterilization such as autoclaving. E. fecaelis was used as a experimental microorganism instead of oral flora. Experimental bowl with 2 cm of rectangular cavity was fabricated for handpiece operating instead of oral cavity. Latex covers ($Orokeeper^{(R)}$, Orobiotech Co., Korea) and several handpieces were used after sterilization by autoclave. Four experiments were performed to evaluate bacterial contamination related with (1) various parts of dental handpiece, (2) swabbing time with alcohol sponge, (3) postoperative air-water spraying time and (4) consecutive use of latex covers without autoclaving. The results show that face of handpiece uncovered with latex cover was severely contaminated than the covered area and that most bacteria were removed by swabbing face and head area of dental hand-piece and by air-water spraying more than 15 seconds nearly up to the level of sterilization. Conclusively it can be suggested that use of latex cover for handpiece during dental procedure, swabbing with alcohol sponge is air-water spraying for more than 15 seconds after use of dental handpiece should be very useful and practical for prevention of cross infection and should be an alternative method for the sterilization of dental handpiece under some difficult situations not being able to sterilize a handpiece with autoclave.

• Food Science and Preservation
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• v.15 no.4
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• pp.550-555
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• 2008

This study analyzed 102 samples from 24 local areas to monitor patulin contamination of apples for processing by the areas. According to the analysis, patulin was detected in 47 samples among totally 92 ones and those of 15 samples from 12 areas were found to be 50 or more ppb so measures to deal with the patulin contamination were necessary. As ways to reduce residues of patulin, when 200 ppm ascorbic acid were treated with they was decreased by 93.4% to 12.89 ppb, and when 100 ppm activated carbon was added they were declined by 95.8% to 2.68 ppb. Treatment with pectinase did not show any significant difference and effects of temperature was not considerable under established sterilizing conditions(90, 105, 120, 135 and $150^{\circ}C$/25 sec). In conclusion, treatment with ascorbic acid and activated carbon on apple juice was found to decrease residues of patulin but more systemic researches were needed to determine it in the future.

• Journal of the East Asian Society of Dietary Life
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• v.17 no.6
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• pp.822-826
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• 2007

This study was conducted to determine the effects of a 0.5% sodium alginate eggshell coating, that was applied at two temperatures, 5 and $25^{\circ}C$, by examining the degree of microbial inhibition on the eggshell surface as well as the coating's effects on egg quality during storage. A significant portion of human Salmonella enteritidis infection is traced to food contamination, and eggs are often highly exposed to this type of contamination. The 0.5% sodium alginate coating's effect for inhibiting microbial growth on the eggs, at $25^{\circ}C$ for 7 days, was one hundred thousand times more effective than that of the uncoated eggs. The pH level in eggs increases as the eggs lose $CO_2$ and as the storage temperature increases. We found that the pH of the coated eggs was lower than that of the uncoated eggs. The pH for the uncoated eggs changed from 7.72 to 7.94 over 30 days of storage at $5^{\circ}C$. However, when the eggs were coated with 0.5% sodium alginate, the pH changed from 7.72 to 7.85 over 30 days of storage at $5^{\circ}C$. The Haugh unit was 66.02 for the uncoated eggs and 70.37 for the 0.5% sodium alginate coated eggs after 30 days of storage. The yolk index of the eggs coated with sodium alginate was higher than that of the uncoated eggs after 30 days. These results indicate that a sodium alginate coating on eggs can serve as protection from microbes and is effective in preserving the interior quality of eggs.

• Korean Journal of Plant Resources
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• v.12 no.1
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• pp.1-9
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• 1999

The experiments were carried out to determine the optimum conditions for the induction of hairy roots in ginseng(Panax ginseng C.A. Meyer) by Agrobacterium spp. We were examined the antibiotics resistance of Agrobacterium spp and various ginseng parts, and the media for induction of hairy roots. The optimum concentration of NaOCl for sterilization of ginseng root segments without tissue damage with reduce of contamination was 7% NaOCl for 15-20 min and 9% NaOCl for 5 min, respectively. The more ginseng ages, the more contamination of ginseng root segment by sterilized in 7% NaOCl for 20 min, and especially in ginseng root segments with epidermis in six-year old roots. The growth of Agrobacterium spp were inhibited, but ginseng root segments was death in 30mg/L tetracycline. In 500mg/L cefotaxime or 500mg/L carbenicillin, the growth of Agrobacterium sup were inhibited, and root segments was grown normally. The optimum conditions for induction of hairy roots were using the root segments of three-year old ginseng cultured in 1/2MS medium supplemented with 500mg/L cefotaxime, and inoculation of Agrobacterium to root segments were better co-culture than smear method. After 2 weeks co-culture, the callus induced in cambium of root segments cultured in 1/2MS solid medium with 500mg/L cefotaxime. And then after 2 weeks, ginseng hairy roots were induced in callus of root segments. PCR analysis of rot C gene fragment confirmed that hairy roots were transgenic tissues.

• Journal of Plant Biotechnology
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• v.34 no.1
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• pp.11-17
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• 2007

Previously developed transgenic watermelon rootstocks (gongdae) inserted by CGMMV-CP were examined to test the virus tolerance levels. In the restricted plastic house, the $T_{3}$ watermelon rootstock showed tolerance to CGMMV until 70 days after inoculation on the leaves while the non-transformed watermelon rootstock became susceptible at 20 days after inoculation. In the field, tolerance efficiency of transgenic rootstocks maintained up to 40% at 71 days after contamination with CGMMV in the soil while all of the non-transformed rootstocks became susceptible at 37 days with the same condition. In the same field, transgenic rootstocks showed more tolerance to CGMMV than the non-transformed rootstocks as those were inoculated on the leaves, but it showed only 10 days delay before being susceptible. Therefore, transgenic rootstocks have a characteristic of delay effect against CGMMV susceptibility, rather than resistance character. From $T_{3}$ rootstocks homozygous for the CGMMV-CP horticulturally favorable individuals were selected for further breeding and a transgenic line was finally obtained at the $BC_{1}T_{5}$. A material transfer experiment was conducted to find out if the DNA, RNA or expressed protein in the transgenic rootstocks could move to the grafted scion (non-transformed watermelon, Super-Kumcheon). PCR, northern, and western blot analysis were performed and no evidence of transferring of those materials from rootstock to scion was ever found.

• Journal of Soil and Groundwater Environment
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• v.14 no.2
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• pp.1-9
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• 2009

This study was objected to identify the effect on water quality and contamination by non-agricultural facilities in 'A' reservoir watershed located in OO city, Kyounggi-do, Korea. Ground- and stream water samples showed (Na+K)-Cl, Ca(Cl, SO$_4$) and Ca-Cl type in an illegally discharging area of sewage and a densely industrial area indicating water contamination. Stream water of an illegally discharging area of sewage had high COD, T-N and T-P. In this area, direct incoming of sewage into stream water was induced ground water system by well pumping, and it made a progress of ground water contaminations with those components. Groundwater of a densely industrial area showed high concentrations of T-N, NO$_3$N. From a nitrogen isotope analysis, stream water of an illegally discharging area of sewage has ${\delta}^{15}N-NO_3$values of 0.7%0 was strongly affected by nitrogen originated from agrochemicals, and a densely industrial area of 19.7%0 from septic system. Ground- and stream water of a livestock fanning area were contaminated with NH$_3$-N and Mn, which was affected by intensive livestock facilities. SAR-conductivity plot indicates the water does not pose either alkalinity or salinity hazard for irrigation. COD, T-N, T-P, NO$3$-N, NH$_3$N and Mn concentrations from contaminated areas were diminished by mixing with 'A' reservoir water. There were no water contaminations in silver towns, vacationlands around reservoir and golf links. Consequently, it should be made a plan of systematic managements for past and- present possible contaminants and sewage systems in preventing water contamination by non-agricultural facilities.

• Korean Journal of Environmental Agriculture
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• v.34 no.2
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• pp.69-76
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• 2015

BACKGROUND: Contamination of soils by heavy metals is the serious environmental problem. In particular, industrial processing is one of the main sources of heavy metal contamination. The objective of this study was to investigate the distribution characteristics of heavy metals in soils collected from industrial complex. METHODS AND RESULTS: In this study, the soil contamination and enrichment factor (EF) of heavy metals were investigated in three national industrial complexes such as Yeosu, Ulsan and Sihwa Banwal industrial complexes. The target heavy metals includes Cd, Cu, As, Hg, Pb, Cr, Zn, and Ni. The results showed that the contents of Cd, Hg, Pb, Zn and Ni in Yeosu and the contents of Cu, As and Cr in Sihwa Banwal were higher than in any other industrial complex. The results of principal component analysis(PCA) in Yeosu, Ulsan and Sihwa Banwal complex could be explained up to approximately 81.4, 69.1 and 70.9% by two factor, respectively. Enrichment factors of Cd, Pb and Zn in all the investigated industrial complexes were above 1.0 that was the value judged to be a high contamination. And EF of Cr was above 1.0 in Sihwa Banwal complex. EF of Zn in all sites was generally high from the other heavy metals. CONCLUSION: Therefore, soils maybe significantly affected by heavy metals (especially, Cd, Pb and Zn) present in the emissions from industrial complexes.