• Journal of Korea Soil Environment Society
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• v.5 no.2
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• pp.3-12
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• 2000

This study was carried out to evaluate the effect of aeration on removal of phenolic compounds in soils. Phenol, 2,4-dichlorophenol, and pentachlorophenol as phenolic compounds were chosen in this study. Texture of soil used was sandy loam. Temperature and moisture content of the soils in lab-scale reactors were maintained at $25^{\circ}C$ and at 15%, respectively. Phenolic compounds vaporized from reactors were trapped by methylene chloride solution. Phenolic compounds were applied to the soils as individual compound Aeration improved the phenol degradation rate in soil, while it did not in case of 2,4-dichlorophenol and pentachlorophenol. The amount of phenol vaporized by aeration was only 0.3of of that of initial phenol compound added to the soil. First order kinetics described the degradation rates of phenolic compounds better than zero order kinetics.

• Journal of fish pathology
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• v.18 no.1
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• pp.81-89
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• 2005

The toxic effects of pentachlorophenol (PCP) on haematological parameters in olive flounder (Paralichthys olivaceus) after chronic exposure to dietary PCP (0.1, 0.5 and 1.0 mg/kg diet) for 2, 4 and 6 weeks were studied. A significant decrease in total RBC count, haemoglobin concentration and hematocrit value was noted in fish exposed to PCP compared to the non-exposed fish. The PCP treatment group showed significantly lower concentration of serum total protein and albumin, and significantly higher serum chloride, magnesium and total bilirubin levels compared with those in the control group. However, PCP had no major effects on serum glucose, total cholesterol, phosphate and calcium ions in flounder. These results demonstrated that PCP have induced adverse haematological impacts in the olive flounder, Paralichthys olivaceus. Because we found damages in blood-forming function and disruption in blood homeostasis due to chronic exposure to PCP, it is needed to develop further experimental studies for the risk assessment of this environmental pollutant.

• Environmental Analysis Health and Toxicology
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• v.25 no.3
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• pp.223-228
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• 2010

Neocaridina denticulata is a small freshwater shrimp indigenous to Korea. As an indigenous species has long-adapted to particular water environments, the species can be a suitable indicator to assess environmental risks caused by hazard chemicals in the particular site. Thus Neocaridina denticulata, a small freshwater shrimp indigenous to Korea, is worth considering for a test species for such purpose. N. denticulata were exposed to pentachlorophenol sodium salt, sodium azide and potassium dichromate using automatic flow-through system for 96 hours. The 96 hr lethal concentrations ($LC_{50}$) of these chemicals were calculated as $0.53{\pm}0.09\;mg/L$, $2.40{\pm}0.61\;mg/L$ and $1.21{\pm}0.09\;mg/L$ respectively and showed relatively small deviation from repetitive test results. When compared with the toxicity values of other species for each chemical, N. denticulata had moderate or high sensitivity to the toxicity of these chemicals. It can be concluded that N. denticulata is a good test species to evaluate acute toxicity of various hazardous chemicals.

• Journal of the Korean Society of Groundwater Environment
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• v.4 no.1
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• pp.14-19
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• 1997

Laboratory experiments were conducted to study the effects of pH and salt level on the soil sorption equilibrium of pentachlorophenol (PCP) which is hydrophobic and ionogenic. Experimental results indicated that the sorption equilibrium constant (Kp) of PCP increased with decreasing pH. A quantitative sorption model involving linear isotherms was estabilished to predict the pH effect on the PCP sorption equilibrium over the pH range from 3 to 8. The model prediction was in good agreement with the experimental data. Also, the Kp increased with salt concentration over the entire pH range. At added salt levels less than 0.1M, increase in Kp was larger than when the added levels were higher than 0.1M. Salt might increase the PCP sorption by inducing 'salting out-effect' or by forming deprotonated PCP-cation ion pairs such as PCP$\^$-/K$\^$＋/. Taking the pH range (5-8) and the salt content (up to 50 g/L) in the groundwater of Metropolitan landfill sites into consideration, the results indicated that the retardation factor of PCP in this area might range from 3 to 550 depending upon pH and salt content.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.7
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• pp.846-851
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• 2007

This study was performed to compare and to examine the degradation efficiencies and degradation mechanism of pentachlorophenol(PCP) by UV, $UV/H_2O_2$, $Fe^{2+}$, $Fe^{2+}/H_2O_2$, and $UV/Fe^{2+}/H_2O_2$ processes. The pseudo-first order rate constant was compared in each process. The addition of $H_2O_2$ increased the rate constant by 13 times compared to the reaction with UV alone. The reaction rate in $Fe^{2+}$ reaction with PCP increased 4 times and 7.25 times by adding 180 mM $H_2O_2$ and 16 mM $H_2O_2$, respectively. Compared to that with $Fe^{2+}/H_2O_2$, the rate constant of the reaction with UV alone reaction increased 3.1 times. These results indicates the enhancement of reaction rate is closely related to the generation of OH radical. The degree of the iron sludge production observed in $Fe^{2+}/H_2O_2$ reaction was significantly reduced by irradiating UV in this process.

• Microbiology and Biotechnology Letters
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• v.29 no.2
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• pp.115-121
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• 2001

Biological Treatment of Wastewater Containing Chlorinated Phenols by a Mixed Culture. Lee, Wan-Seok1, Sang-Wook Jung, Chan-Sun Park, Byung-Dae Yoon, Jang-Eok Kim\ and Hee-Mock Oh*. Environmental Bioresources Laboratory, Korea Research Institute of Biosicence and Biotechnology, Taejon, Korea, 1 Department of Agricultural Chemistry, Kyungpool< National University, Taegu, Korea - The biodegradation of chlorinated phenols in an artificial wastewater was investigated using a mixed culture. The mixed culture was composed of 8 microorganisms isolated from the soil contaminated with various chlorinated phenols. Pseudomonas sp. BM as a main constituent of a mixed culture was Gram-negative, catalase- and oxidase-positive, and rod-shaped, and did not grow at 41°C. It degraded 99% of initial 500 mg!1 of pentachlorophenol (PCP) in the minimal salts medium as a sole source of carbon and energy within 3 days. The degradation efficiency of Pseu.domon.as sp. BM was not affected by the other organic carbon and nitrogen compounds. Pseudomonas sp. BM was able to grow in a broad range of pH 5 - 8, and degrade 2,000 mg/1 PCP. In the experiment with an artificial wastewater containing chlorinated phenols, the degradation efficiency of the mixed culture was the range of 73% (2,4-dichlorophenol) -96% (2-chlorophenol) during an incubation of 7 days. In a continuous culture experiment, the degradation efficiency of mixed culture plus activated sludge was about 2 times higher than that of the control containing only activated sludge. These results indicate that it is possible to apply the mixed culture to other wastewaters containing chlorinated phenols. Key words: Biodegradation, chlorinated phenols, pentachlorophenol, Pseudomonas sp. BM

• Applied Biological Chemistry
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• v.42 no.4
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• pp.330-335
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• 1999

Pentachlorophenol(PCP), which is very persistent in soil and water environment, was tried to detoxify with oxidoreductive catalysts(peroxidase, laccase, tyrosinase and birnessite). To find out detoxification of PCP, the transformation of PCP through oxidative coupling was investigated in the presence of various oxidoreductive catalysts. PCP incubated with peroxidase was significantly transformed, however, in case of tyrosinase, the transformation was negligible. Using peroxidase, the optimal reaction condition was pH 5.6 and $16^{\circ}C$. The transformation of PCP was very fast in initiation step until 30 min but, that was not observed after 180 min. The transformation of PCP was increased by increasing peroacidase amount. When the effect of humic monomer was investigated as co-substrate on the transformation of PCP, the transformation of PCP was mostly decreased in the incubation with peroxidase, laccase, and birnessite. The transformation of PCP, however, was slightly increased by the incubation with tyrosinase in the presence of humic monomers as co-substrate, except catechol. On the basis of the results obtained, it may be suggested that PCP is able to be effectively detoxified through oxidative coupling mediated with oxidoreductive catalysts.

• Korean Journal of Soil Science and Fertilizer
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• v.33 no.4
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• pp.261-265
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• 2000

To develope the enhanced bacterial strains capable of biodegradation for various chlorinated aromatic compounds, 100 bacterial strains were isolated from soil samples of suburbs of Taejon, Cheongju, and Jeonju by the enrichment culture. These strains can degrade pentachlorophenol (PCP) which is a kind of wood preservatives. Nineteen strains of the isolates were selected by fast colony-forming rate on solid minimal media containing PCP as an only source of carbon and energy. These strains were identified to genus level. Fifteen strains were identified as Pseudomonas, 1 strain as Acinetobacter and 3 strains were not. Genus Alcaligenes strains were not found among them. Pseudomonas sp. MU135. MU139, MU163 and MU 184 were able to degrade for 4 kinds of chlorinated compounds, PCP, 2,4-D, MCPA and 3CB. Pseudomonas sp. If was observed that MU139 exhibits the highest degradability in liquid minimal media at 72 hours after inoculation. Pseudomoans sp. MU147, MU177, MU184 and MU192 also degraded the compounds at higher rates. As the results, Pseudomonas sp. MU139 and unidentified strain MU184 had biodegrability for broad range of chlorinated compounds and higher rates of degradation for PCP.

• Korean Journal of Microbiology
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• v.33 no.2
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• pp.149-156
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• 1997

We have employed comparative RFL,P(Restriction Fragment Ixngth Pol~iniorphism) analysis and molecular phylogenetic techniques to investigate the diversity of uncultured microorganisms associated with the anaerobic PCP degradation in PCP-adapted enrichment cultures inoculated by samples from anaerobic cewage sludgc(Jangrim, Pusan) and leachate of landfill site(Kimhae). 16s rDNA cloncs were obtairted by PCR amplification of mixed population DNAs extracted directly from the nonactive and active stage ol each PCP-adapted culture. After three rounds of comparative RFLP analyses. two RFLP types. designated as Ala and Hld, were found prevalent and common in both active stage samples. Thc analysis of phylogenctic diversity bawd on the 5'-terminal 180 nt of sequences from whole clones of the Ala and Bld RFLP types showed close similarity among themselves. In case of Bld clones, 7XQ of them shared identical sequences. Thcse resuliq suggest that the clones of both RFLP types wcre originated from highly affiliated microorganisms which are e~iriched as a result of metabolic activity to PCP. The full-length 16s rRNA sequence of each representative clone from both RFLP types was determined. and an Ala clone w i n found to he related to Clo.strrdiurn ulfutzac~(Genk~ank No. Z69203) and a Bld clone to Thermobacteroides proteolyticus(Genbank No. X09335), with sequence similarities of 89%' and 97%. respectively.

• Journal of fish pathology
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• v.23 no.2
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• pp.189-198
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• 2010

Experiments were carried out to determine the hematological changes in olive flounder, Paralichthys olivaceus, after sub-chronic dietary pentachlorophenol (PCP) concentrations (0, 0.1, 0.5 and 1.0 mg/kg) exposure 6 weeks. The RBC count, Ht and Hb were significantly decreased in PCP 0.5 mg/kg exposed flounder compared to control group. The flounder exposed to PCP concentration 0.5 mg/kg started to increase significantly in serum magnesium concentrations after 4 weeks. The low concentration of serum calcium concentration was observed at 6 weeks of the experiment in PCP concentration 0.5 mg/kg. Although serum total protein concentrations was significantly reduced compared to the control group at PCP concentration 0.5 mg/kg, serum glucose concentration was found to be significantly increased over the control group. A significant increment of GOT, GPT and LDH activities in the flounder serum was noticed after 4 weeks at PCP concentrations over 0.5 mg/kg without typical changes of Al-P. These results indicate that flounder can be affected by PCP in terms of inorganic matter, organic matter and enzyme activity in serum when they were exposed to the PCP concentrations 0.5 mg/kg or higher.