• Korean Journal of Ecology and Environment
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• v.35 no.1 s.97
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• pp.45-51
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• 2002

This study was investigated to tile influences of clearcutting of timber harvesting on stream water quality at a natural deciduous forest catchment within the Seoul National University Research Forests in Mt. Baegun, Chunnam province during the periods of 1993 to 2001. Soil chemical ingredients and stream water qualities were monitored at 13 ha clearcutting site, non-treatment site and included in these catchment nearby. After the harvesting first and End years, the levels of total- N,　and exchangeable ions ($K^+,\;Na^+,\;Ca^{2+},\;Mg^{2+}$) were decreased the values of before　harvesting, and after the harvesting 111th years and eighth years, respectively. But the chemical characteristics of soil were not changed at all. pH of water in the harvesting area was 6.5 in stream water. Among the nutrient, Cd, Pb, Cu, and phosphate were not found, and the level of BOD reached at the level of the domestic use for drinking. Turbidity, odor, taste, $NH_4\;^+-N,\;NO_3\;^--N$, standard plate count, and coliform were also low enough to be used as the domestic use for drinking in the near villagers. Total amount of cation, total amount of anion and total amount of ion in clearcutting site, non- treatment site and included in these catchment nearby were higher than clearcutting site and non- treatment site. But, there was no great difference.

• Korean Journal of Environmental Agriculture
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• v.19 no.2
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• pp.110-115
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• 2000

This study was conducted to monitor the irrigation water qualities along Dong-Jin river watershed. The water quality was surveyed at 6 sites from April to september during $1994{\sim}1998$. And the results were as follows : In July and August, water quality was better than that of any other months due to dilution with rainwater. Whereas, it became worse in April but it involved lower contents than limitted contents affected to the crop damage. Content of inorganic components was higher at Jeong-up and Won-pyeong stream. The reason for it that Jeong-up stream was deteriorated with sewage water from Jeong-up city, and Won-pyeong stream has narrow width. Water quality in upstream of Dong-Jin river, was evaluated best conditions in all sampling sites. For investigated period, water quality got worse from 1994 to 1995 but it was getting better to 1998 after 1995, especially at Jeong-up stream. The total equivalent of cation and anion was the highest at April through all months and at Jeong-up stream in sampling sites. Equivalent ratio of cation to $anions({\Sigma}C/{\Sigma}A)$ was higher at May than any other months and lower at Won-pyeong streams than any other sites. The value of most inorganic components was highly correlated with those of other components. But the value of $NO_3\;^--N$ was not correlated with that of most components, and $PO_4\;^{3-}-P$ was not correlated with COD, $NH_4\;^+-N$, $NO_3\;^--N$, $SO_4\;^{2-}$.

• Korean Journal of Environmental Agriculture
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• v.29 no.3
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• pp.266-272
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• 2010

The present study was carried out to assess exposure & risk for Korean by total and inorganic As intake through agricultural products. Total arsenic analysis was performed using microwave device and ICP-MS. 50% MeOH extraction and anion-exchange HPLC-ICP-MS method has been used to determine arsenic species. 329 samples covering 20 kinds of agricultural products were collected from various retail outlets and markets across Korea. The concentration of total As was in the range of 0.001~0.718 mg/kg, while inorganic and organic arsenic species in all samples was not determined. For risk assessment, probable daily intake was calculated and compared with provisional tolerable weekly intake (PTWI, 15 ${\mu}g$/kg b.w./week for inorganic arsenic) established by JECFA. The median daily exposure to total and inorganic As by intake of agricultural products except rice was ranged 0.0002~0.012, 0.0001~0.001 ${\mu}g$/kg b.w./day, corresponding to 0.01~0.5%, 0.002~0.1% of PTWI, respectively. The median level of total and inorganic As intake through rice was 0.603 and 0.041 ${\mu}g$/kg b.w./day, and 28.1% and 1.9% of PTWI, respectively. Therefore, the level of overall exposure to arsenic for Korean through agricultural products was below the recommended JECFA levels, indicating of least possibility of risk.

• The Plant Pathology Journal
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• v.29 no.4
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• pp.386-396
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• 2013

Reactive oxygen species (ROS) generation in tomato plants by Ralstonia solanacearum infection and the role of hydrogen peroxide ($H_2O_2$) and nitric oxide in tomato bacterial wilt control were demonstrated. During disease development of tomato bacterial wilt, accumulation of superoxide anion ($O_2{^-}$) and $H_2O_2$ was observed and lipid peroxidation also occurred in the tomato leaf tissues. High doses of $H_2O_2$ and sodium nitroprusside (SNP) nitric oxide donor showed phytotoxicity to detached tomato leaves 1 day after petiole feeding showing reduced fresh weight. Both $H_2O_2$ and SNP have in vitro antibacterial activities against R. solanacearum in a dose-dependent manner, as well as plant protection in detached tomato leaves against bacterial wilt by $10^6$ and $10^7$ cfu/ml of R. solanacearum. $H_2O_2$- and SNP-mediated protection was also evaluated in pots using soil-drench treatment with the bacterial inoculation, and relative 'area under the disease progressive curve (AUDPC)' was calculated to compare disease protection by $H_2O_2$ and/or SNP with untreated control. Neither $H_2O_2$ nor SNP protect the tomato seedlings from the bacterial wilt, but $H_2O_2$ + SNP mixture significantly decreased disease severity with reduced relative AUDPC. These results suggest that $H_2O_2$ and SNP could be used together to control bacterial wilt in tomato plants as bactericidal agents.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.4 no.2
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• pp.189-197
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• 1994

Analytic methods for Cr(VI) level in industrial hygienic field were suggested by the National Institute for Occupational Safety and Health(NIOSH method 7600, 7604). There were growing needs for measurement of Cr(III) and Cr(VI) levels simultaneously. Two analytical methods were suggested to determine Cr(III) and Cr(VI) levels simultaneously. The one is method by using reversed phase high peformance liquid chromatography(HPLC) and the other is by using ion exchange HPLC. The purpose of this work was to evaluate the usefulness of these two analytic methods. For the difference of ionic charges of Cr(III)-ethylendiamine tetraacetic acid(EDTA) chelate and $CrO_4{^-2}$, we could detect them simultaneously by ion exchange HPLC. Also, we attempted to determine the levels of Cr(III) and Cr(VI) chelated with sodium diethyldithiocarbamate(NaDDTC) by using reversed phase HPLC. The confirmation of Cr(III) and Cr(VI) were checked by fraction collector and nameless atomic absorption spectrometer. The optimal conditions for the formation of Cr(III)-EDTA chelate were two hours incubation period with pH 5. Cr(III)-EDTA and Cr(VI) in EDTA solution were successfully separated by anion exchange column using $Na_2CO_3/NaOH$ mixture as mobile phase. Peaks of Cr(III)-EDTA and Cr(VI) in EDTA were identified at 5 minutes and 7 minutes of retention time respectively by the ion exchange HPLC. The formation of Cr(III)-NaDDTC and Cr(VI)-NaDDTC chelates were twelve hours incubation period. Cr(III)-NaDDTC and Cr(VI)-NaDDTC chelates were separated by reversed phase column using methanol and water mixture as mobile phase. Peaks of Cr(VI)NaDDTC and Cr(III)-NaDDTC chelates were identified at 13 minutes and 26 minutes of retention time respectively by the reversed phase HPLC. Due to reduction of Cr(VI) to Cr(III), it seems to be not suitable for simultaneous determination of Cr(III)-NaDDTC and Cr(VI)-NaDDTC chelates by reversed phase HPLS. Simultaneos determination of Cr(III) and Cr(VI) by ion exchange HPLC was more accurate and simple method.

• The Journal of Internal Korean Medicine
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• v.31 no.1
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• pp.153-165
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• 2010

Objectives : The aims of this study were to investigate the cytoprotective, antioxidative and inflammation genes inhibitory effects of Patriniae Radix on the mouse LLC-$PK_1$ cells (renal epithelial cells). Methods : The cytoprotective effect of Patriniae Radix was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The antioxidative effect was measured in terms of generation amount of superoxide anion radical (${\cdot}{O_2}^-$) by 2',7'-dichlorodihydrofluorescein diacetate (DCFDA), nitric oxide (NO) by 4,5-diaminofluorescein (DAF-2), peroxynitrite ($ONOO^-$) by dihyldrorhodamine 123 (DHR 123) and prostaglandin $E_2$ ($PGE_2$) by $PGE_2$ immunoassay on $H_2O_2$-treated LLC-$PK_1$ cells. For measuring of inflammation genes inhibitory effects, western blot was performed to detect IKK-$\alpha$, phospho-$I{\kappa}B-\alpha$, NF-${\kappa}B$ (p50, p65), COX-2, iNOS, IL-$1{\beta}$ and VCAM-1 protein level in cytosol fractions from LLC-$PK_1$ cells. Results : Patriniae Radix extract reduced the $H_2O_2$-induced cell death and inhibited the amount of $H_2O_2$-induced ${\cdot}{O_2}^-$, NO, $ONOO^-$, $PGE_2$ generation dose-dependently on the mouse LLC-$PK_1$ cells in vitro. Also Patriniae Radix extract inhibited the expression of IKK-$\alpha$, phospho-$I{\kappa}B-\alpha$, COX-2, iNOS, IL-$1\beta$ and VCAM-1 genes dose-dependently by means of decreasing activation of NF-${\kappa}B$. Conclusions : According to above results, it was identified that Patriniae Radix had the cytoprotective, antioxidative and inflammation genes inhibitory effects. So it was suggested that Patriniae Radix would be effective to the treatment for the inflammatory process and inflammation-related diseases.

• Korean Journal of Plant Tissue Culture
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• v.21 no.1
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• pp.29-34
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• 1994

The possibility that DNA could move out of the single cells isolated from geranium (Pelargonium zonale hybrids, 'PintoScarlet') callus was determined by the elechophoretic DNA analysis after treatment of low pH, various concentrations of KNO$_3$, 2,4-D, and GA$_3$ followed by the centrifugal force, all of which are hewn to and the physico-chemical properties of the cell wall. The centrifugal force of l,800 xg was need for DNA migration after the above treatment, but 7k300 xg was required without the treatments. In this experiment the optimum concentration (300 mg/L) of sodium dodecyl sulfate (SDS) used as an anion detergent to collect the negatively charged DNA was very critical not to damage the cell wall It can be concluded that the centrifugal force played a key role for the DNA migration through the cell wall, and the treatments of low pH (4.0), 0.5% KNO$_3$, 1.5 mg/L GA$_3$and 1mg/L 2,4-D further increased the DNA migration.

• Journal of environmental and Sanitary engineering
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• v.7 no.2
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• pp.111-128
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• 1992

According to the increase of population and industrialization, the quality of our drinking water are becoming worse by the contamination of resources, production of THM and other halogenated hydrocarbons during the purifying process, the problem of corroded water supplying pipeline, and the water reservoir tanks, Many people choose groundwater to drink instead of city tap water, but sometimes we get report about groundwater contamination by wastes, swage, septic tank, etc. It is reported that in U. S. over 20% of population are drinking groundwater, but U. S EPA reported the groundwater contamination by pesticides, herbicides, fungicides, fertilizer, and various chemical substances. Craun, et at announced the groundwater contamination by bacteria which are related with poor installation of septic tank. Johnson and Kross mentioned aboutmethemoglobinemia by NO3-N originated from human and animal feces, organic chemicals, and fertilizer, and as the results the infant mortality could be risen. Some scientist also reported the high concentration of metals in groundwaters and some cation and anions, and volatile organic compou nds. Authors investigated 80 groundwaters in urban, agricultural, and industrial area during last 3 month(June - August) to check any drinking water quality parameters are exceeding the standards. The results were as follow. 1, The average value of ammonia nitrate were within the standard, but 11.76% of urban area were exceeded the 10 rpm standard, in agricultural area 42.3175 were exceeded, and in industrial area 20.2% were exceeded the drinking water standard of 10 ppm. the highest concentration was 29.37 ppd in industrial area. 2. The mean value of metals is not exceeded the standard, but there were some groundwater whose Mn value was 0.424 ppm(standard is 0,3 ppm) in urban area, 0.737 rpm in agricultural area, and 5.188 ppm in industrial area. The highest Zn value was 1.221 ppm (standard is 1.0 ppm)was found in industrial area. 3. The percentage of contamination by general bacteria was 8.82% in urban area, 15.38% in agricultural area, and 15.00% in industrial area. Escherichia coil group was also contaminated by 35.29% in urban area, 30.76% in agricultural area, and 30.00% in industrial area. 4, The pH value was within the standard which means there was no influence by acid or alkali chemicals, nor acid rain Through the above results, all the groundwater should be tested to check the safety for drinking water and should make some alternative methods suitable for drink.

• Korean Journal of Soil Science and Fertilizer
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• v.16 no.4
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• pp.318-324
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• 1983

Electrochemical properties of Georgia kaolinite in aqueous suspension were studied by ion adsorption, potentiometric titration, and electrophoretic mobility measurements. Kaolinite in 0.001 M and 0.1 M NaCl solution showed qualitatively both pH independent and pH depender negative and positive charges through pH range 2.5-11.0 when dissolved aluminum ions from kaolinite were considered as well as $Na^+$ and $Cl^-$ as index ions. Electrophoretic mobilities (EM) of 0.02 wt. % kaolinite suspension in distilled water and 0.001 M NaCl solution were approximately constant against mobility measuring time consumed in the electrophoresis cell at different pH values, and isoelectric points(IEP) were around pH 4.7. EM values in 0.1 M NaCl solution were positive and constant against mobility measuring time below pH 4; but above pH 4, EM values were negative for the first 10 seconds followed by positive values which became approximately constant through stepped changes after 10 minutes. Hydrated cations may bind to the six- member oxygen ring sites having multiple partial negative charges on the exterior tetrahedral layer surface by both electrostatic and hydrogen bonding force while hydrated anions bind to the partially positively charged hydrogen atoms on the exterior octahedral layer surface. Parts of the aluminol groups on the exterior octahedral layer surface as well as edge faces may be involved in complex reactions and have both anion and cation exchange capacities in the electrolyte solution above pH 4.

• Journal of Food Hygiene and Safety
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• v.26 no.2
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• pp.166-170
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• 2011

Modem people have begun to have the nationwide interest in the rice wine called Makgeolri which is one of the traditional Korean alcoholic liquors. This study was performed to investigate the effects of San sung Makgeolri extract (SM) on antioxidation together with the determination of pH and dissolved oxygen (DO) in the progress of fermentation in the lipopolysaccharide(LPS)-treated rats. We examined the levels of SOD (superoxide dismutase), CAT (catalase), GPx (glutathione peroxidase) in liver homogenates and the histopathological observations in liver tissue. LPS-treated group markedly decreased the levels of SOD, CAT and GPx. But SM + LPS-treated group significantly increased the levels of them. Furthermore, the antioxidative effects of SM were supported by the histopathological observations in liver tissue which showed severe inflammation and necrosis in LPS-treated group, compared to the attenuated inflammation and necrosis in SM + LPS-treated group. This results suggested that SM could be a candidate of antioxidative material in spite of alcoholic liquors.