• Korean Journal of Soil Science and Fertilizer
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• v.50 no.4
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• pp.235-250
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• 2017

In this study, we monitored 4 volatile organic compounds (VOCs) such as chloroform, dichloromethane, 1,2-dichloroethane, and tetrachloromethane in groundwater samples to determine the detection frequency and their concentrations and evaluated the health risk level considering ingestion, inhalation, and skin contact. 75 groundwater wells were selected. 24 wells were from monitoring background groundwater quality level and 51 wells were from monitoring groundwater quality level in industrial or contamination source area. In the results, the detection frequency for chloroform, dichloromethane, 1,2-dichloroethane, and tetrachloromethane was 42.3%, 8.1%, 6.0%, and 3.4%, respectively. The average concentrations of VOCs were high in the order of chloroform ($1.7{\mu}g\;L^{-1}$), dichloromethane ($0.08{\mu}g\;L^{-1}$), tetrachloromethane ($0.05{\mu}g\;L^{-1}$), and 1,2-dichloroethane ($0.05{\mu}g\;L^{-1}$). Chloroform had the highest detection frequency and average detection concentration. In the contaminated groundwater, the detection frequency of VOCs was high in the order of chloroform, dichloromethane, 1,2-dchloroethane, and tetrachloromethane. The average concentrations for chloroform, dichloromethane, 1,2-dichloroethane, and tetrachloromethane were $2.23{\mu}g\;L^{-1}$, $0.08{\mu}g\;L^{-1}$, $0.07{\mu}g\;L^{-1}$, and $0.06{\mu}g\;L^{-1}$, respectively. All the 4 compounds were detected at industrial complex and storage tank area. The maximum concentration of chloroform, dichloromethane, and 1,2-dichloroethane was detected at industrial complex area. Especially, the maximum concentration of chloroform and dichloromethane was detected at a chemical factory area. In the uncontaminated groundwater, the detection frequency of VOCs was high in the order of chloroform, dichloromethane, and 1,2-dchloroethane and tetrachloromethane was not detected. The average concentrations for chloroform, dichloromethane, and 1,2-dichloroethane were $0.57{\mu}g\;L^{-1}$, $0.07{\mu}g\;L^{-1}$, and $0.03{\mu}g\;L^{-1}$, respectively. Although chloroform in the uncontaminated groundwater was detected the most, the concentration of chloroform was not exceeding water quality standards. By land use, the maximum detection frequency of 1,2-dichloroethane was found near a traffic area. For human risk assessment, the cancer risk for the 4 VOCs was $10^{-6}{\sim}10^{-9}$, while the non-cancer risk (HQ value) for the 4 VOCs is $10^{-2}{\sim}10^{-3}$.

• YAKHAK HOEJI
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• v.13 no.2_3
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• pp.80-83
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• 1969

Acetylsalicylic acid gives a water-insoluble violet complex with $<\alpha>$-Picolin-Cu(II) reagent. The Complex is extractable well with a mixture of $<\alpha>$-Picolin-tetrachloromethane solution. The Complex salt dissolved in the mixed solution shows a maximum absorption at 620 m$<\mu>$. It has a melting point at $171^{\circ}C-$173^{\circ}C and molar ratio of Acetylsalicylic acid: Cu(II): $<\alpha>$-Picolin was estimated as 2:1:2 by continuous variation method and chelate titration method.

• Korean Journal of Environmental Biology
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• v.17 no.4
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• pp.513-519
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• 1999

Volatile organic compounds (VOCs) were analyzed on the seawater from 17 stations in Kwangyang Bay throughtout the year. We could not detect 10 VOCs; methylene chloride, tetrachloromethane, 1, 1, 1-trichloroethane, trichloroethane, 1, 1, 1, 2-tetrachloroethane, trichloroethylene, bromoethane, dibromoethane, bromobenzene, 1-ethyl-3-methylbenzene. The other VOCs-chloroform, 1, 2-dichloroethane, ethylbenzene, benzene, toluene, m, p-xylene, methylethylketone, styrene, hexane-were detected with a little variance according to the sampling stations and the sampling seasons. The concentrations of chloroform (0.6 ~ 49.9 $\mu$g/1) and toluene (0.42 ~ 48.3 $\mu$g/1) were high and they were detected more frequently than the other detected VOCs. We also tried to seek the correlation between the physicochemical environmental factors and VOCs. Only toluene had the high correlation coefficient with the water temperature (r = -0.524) and with the pH (r = 0.319). Correlation between VOCs themselves showed some interesting results. The benzene had high correlation coefficient (r = 0.549 ~ 0.662) with three VOCs such as toluene, m, p-xylene, ethylbenzene. From these results it is suggested that VOCs might be discharged simultaneously in Kwangyang Bay.

• Biomolecules & Therapeutics
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• v.24 no.1
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• pp.40-48
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• 2016

The pregnane X receptor (PXR), a liver and intestine specific receptor,, has been reported to be related with the repression of inflammation as well as activation of cytochromosome P450 3A (CYP3A) expression. We examined the effect of PXR on tetrachloromethane (CCl4)-induced mouse liver inflammation in this work. Ginkgolide A, one main component of Ginkgo biloba extracts (GBE), activated PXR and enhanced PXR expression level, displayed both significant therapeutic effect and preventive effect against $CCl_4$-induced mouse hepatitis. siRNA-mediated decrease of PXR expression significantly reduced the efficacy of Ginkgolide A in treating $CCl_4$-induced inflammation in mice. Flavonoids, another important components of GBE, were shown anti-inflammatory effect in a different way from Ginkgolide A which might be independent on PXR because flavonoids significantly inhibited CYP3A11 activities in mice. The results indicated that anti-inflammatory effect of PXR might be mediated by enhancing transcription level of $I{\kappa}B{\alpha}$ through binding of $I{\kappa}B{\alpha}$. Inhibition of NF-${\kappa}B$ activity by NF-${\kappa}B$-specific suppressor $I{\kappa}B{\alpha}$ is one of the potential mechanisms of Ginkgolide A against CCl4-induced liver inflammation.

• Clean Technology
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• v.22 no.4
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• pp.269-273
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• 2016

The benzylic bromination of methoxyimino-o-tolyl-acetic acid methyl ester (1) into (2-bromomethyl-phenyl)-methoxyimino-acetic acid methyl ester (2) using N-bromosuccinimide in the presence of 2,2'-azobisisobutyronitrile in various reaction solvents were investigated. The efficiency of the reaction was found to be sensitive to the kind of reaction solvents. We found the benzylic bromination of 1 to 2 can be performed in 1,2-dichlorobenzene as reaction solvent superior to the classic Wohl-Ziegler procedure in both reaction time and isolated yield (8 h vs 12 h, 92 vs 79%). This system provides clean, rapid, and high-yielding reactions with replacement of conventional solvents, such as tetrachloromethane, by less-toxic 1,2-dichlorobenzene.

• Journal of Applied Biological Chemistry
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• v.50 no.2
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• pp.78-84
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• 2007

The anti-fibrotic effects of hot water extract of adventitious root culture of Panax ginseng (ARCP) and the possible mechanisms were investigated on $CCl_4-induced$ hepatotoxicity model mice. Fibrosis was induced by a mild treatment of $CCl_4$. Then silymarin as a positive control drug and ARCP or carrier alone as a negative control were treated. Serum GPT, GOT and ALP activity levels were lowered by 25, 21 and 11% for silymarin treated group and by 48, 39 and 14% for ARCP treated group compared to carrier treated alone. Hepatic collagen for ARCP treatment group was reduced by 18% and MDA contents decreased a little more. Pro-fibrotic gene ($TGF-{\beta}1$, TIMP-1 and ${\alpha}-SMA$) expression increased following the $CCl_4$ treatment, but both the silymarin and the ARCP treatments decreased the expressions of these genes by 20% to 50%. The antioxidant effect of ARCP was studied by DPPH free radical scavenging activity. In addition, a generation of reactive oxygen species (ROS) was also reduced in $H_2O_2-treated$ HepG2 cells upon the ARCP treatment. In summary, ARCP has antioxidant property, and can have some protection against oxidative stress; more importantly, ARCP can efficiently protect mice against $CCl_4-induced$ fibrosis.

• Journal of Soil and Groundwater Environment
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• v.7 no.3
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• pp.95-102
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• 2002

Manganese oxide/ hydrogen peroxide($MnO_2$/${H_2}{O_2}$) reactions were investigated as an alternative to Fenton-like reaction to reduce chlorinated organic compounds in groundwater This system showed high degradation of CT with low ${H_2}{O_2}$concentration($\leq$294mM) at neutral condition, and CT degradation increased with increasing pH values. The rate of CT degradation was not so much dependent on increase in $MnO_2$concentration since increase in production of oxygen during the reaction obstructed reaction of ${H_2}{O_2}$ on the surface of $MnO_2$. These results show that $MnO_2$catalyzed Ponton-like reaction could be a potential alternative method for treating chlorinated organic compounds in groundwater.