• Journal of the Korea Organic Resources Recycling Association
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• v.11 no.4
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• pp.49-56
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• 2003

The strain Ralstonia eutopha JMP134 (formerly Alcaligenes eutrophus JMP134) can degrade trichloroethylene(TCE) through a chromosomal phenol-dependent pathway. The phenol hydroxylase was previously found to be a single responsible enzyme for TEC degradation. Here, we demonstrate that a recombinant bacterium, R. eutopha AEK301, one of Tn5-induced mutants of JMP134 containing a recombinant plasmid pYK3011, degrades TCE in the absence of inducer, phenol and in the presence of various carbon sources. Complete removal of TCE ($50{\mu}M$) was observed in minimal medium containing only 0.05% ethanol as a carbon source within 24 hours. The bacterium removed $200{\mu}M$ of TCE to below detectable level within two days under non-selective pressure. When TCE concentration was increased up to $400{\mu}M$, the degradation had been continued until two days, then ceased with removal of 70% of detectable TCE.

• Journal of the Korea Organic Resources Recycling Association
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• v.12 no.1
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• pp.67-74
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• 2004

A bacterium which grow on phenol as an only carbon and energy source was isolated from the sewage sludge at Nangi municipal wastewater treatment plant in Seoul. This bacterium was found to be a Gram negative rod with high motility, and well grew on 0.05%, 0.1%, and 0.15% of phenol. No matching strain was found from the result of the BBL test. Phylogenetic analysis of the strain by comparison of the 16s-rDNA has revealed that this bacterium has 99% of similarity with Stenotrophomonas maltophilia strain of Xanthomonas group, which belongs t the Gamma (${\gamma}$) subdivision of Proteobacteria. This strain has also shown 98% of similarity with nitrogen fixing bacterium MAGDE3 and Pseudomonas cissicola strain, and 97% of similarity with Stenotrophomonas sp. LMG198 and Xanthomonas cucurbitae.

• Journal of Life Science
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• v.12 no.5
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• pp.561-565
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• 2002

Pseudomonas sp. EL-041 was previously isolated from phenol-acclimated activated sludge. This bacterium was capable of degrading phenol and cometabolizing trichloroethylene (TCE). In this study, we report the identification of trichloroethylene- degrading enzyme in Pseudomonas sp. EL-041 by the investigation of enzyme activity and DNA sequencing of specific phenol oxygenase gene. As the results of experiment, trichloroethylene-degrading enzyme in Pseudomonas sp. EL-041 was monooxygenase and suspected to phenol hydroxylase.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 1998.04a
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• pp.179-181
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• 1998

• Journal of Korea Soil Environment Society
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• v.1 no.1
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• pp.39-46
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• 1996

For the purpose of development of bioremediation technology for soil contaminated by chlorinated phenols, this study was focused on the isolation and characterization of bacteria capable of degrading chlorinated phenols, the establishment of analytical methods for chlorinated phenols, and the investigation of the contaminated sites. One site near the Incheon Industrial Complex was identified as a pentachlorophenol (PCP)-contaminated spot. The soil brought from the PCP-contaminated site contained 10-100$mu\textrm{g}$/g wet soil of PCP. Many bacterial strains capable of growing on a minimal medium containing PCP were isolated from 15 soil samples collected throughout the land, and among them, 10 active isolates were finally selected for the further studies on the biodegradability and for the use in in situ bioremediation of contaminated soil. These isolates showed species-specific pattern in PCP-decrease and cell growth in a minimal medium containing 500-1,000mg/ιPCP. Strain Bul degraded 90% of PCP at 216 hrs after incubation. Expecially, strain Bu34 was capable of degrading 4,000mg/ι PCP and was identified as Pseudomonas putida Bu34. It is seemed that the isolated active bacteria could be effectively used for the bioremediation of PCP-contaminated sites.

• Microbiology and Biotechnology Letters
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• v.26 no.4
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• pp.303-308
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• 1998

A bacterial strain which utilizes phenol under denitrifying condition was isolated from the industrial waste water collected from the Chong-ju Industrial Complex. The strain was identified as Pseudomonas species from the morphological, physiological, and biochemical characteristics and designated as HL100. The strain can utilize phenol as the sole source of carbon and energy when nitrate is provided as the terminal electron acceptor. The isolated strain completely degraded 3 mM of phenol within 110 hour with concomitant reduction of nitrate to nitrite. The observed maximum doubling time was 20 hours. Under appropriate condition, complete reduction of nitrate to atmospheric N$_2$ was observed indicating that the isolated strain could perform complete steps of denitrification. The strain showed optimal growth at pH 7.0 and temperature of 37$^{\circ}C$ under denitrifying phenol-degrading condition. The strain can also utilize toluene as the sole carbon and energy source under the same growth condition. However, no growth was detected on xylene and benzene.

• Journal of Life Science
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• v.24 no.9
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• pp.988-994
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• 2014

The effluents of chemical and petroleum industries often contain non-biodegradable aromatic compounds, with phenol being one of the major organic pollutants present among a wide variety of highly toxic organic chemicals. Phenol is toxic upon ingestion, contact, or inhalation, and it is lethal to fish even at concentrations as low as 0.005 ppm. Phenol biodegradation has been studied in detail using bacterial strains. However, these microorganisms suffer from substrate inhibition at high concentrations of phenol, whereby growth is inhibited. A phenol-degrading bacterium, P21, was isolated from oil-contaminated soil. The phenotypic characteristics and a phylogenetic analysis indicated the close relationship of strain P21 to Rhodococcus pyridinovorans. Phenol biodegradation by strain P21 was studied under shaking condition. The optimal conditions for phenol biodegradation by strain P21 were 0.09% $KNO_3$, 0.1% $K_2HPO_4$, 0.3% $NaH_2PO_4$, 0.015% $MgSO_4{\cdot}7H_2O$, 0.001% $FeSO_4{\cdot}7H_2O$, initial pH 9, and $20-30^{\circ}C$, respectively. When 1,000 ppm of phenol was added to the optimal medium, the strain P21 completely degraded it within two days. Rhodococcus pyridinovorans P21 could grow in up to 1,500 ppm of phenol as the sole carbon source in a batch culture, but it could not grow in a medium containing above 2,000 ppm. Moreover, strain P21 could utilize toxic compounds, such as toluene, xylene, and hexane, as a sole carbon source. However, no growth was detected on chloroform.

• Journal of Environmental Health Sciences
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• v.24 no.3
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• pp.54-62
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• 1998

20 bacterial strains capable of growing on phenol minimal medium were isolated from soil and wastewater by the enrichment culture technique, and among them, one isolate which was the best in the cell growth was selected and identified as Bacillus sp. SH3 by its characteristics. Strain SH3 could grow with phenol as the sole carbon source up to 15 mM, but did not grow in minimal medium containing above 20 mM of phenol. The optimal conditions of temperature and initial pH for growth and phenol degradation were 30$^{\circ}$C and 7.5, respectively. This strain could grow on various aromatic compounds such as catechol, protocatechuic acid, gentisic acid, o-, m-, p-cresol, benzoic acid, p-hydroxybenzoic acid, anthranilic acid, phenyl acetate and pentachlorophenol, and the growth-limiting log P value of strain SH3 on organic solvents was 3.1. In batch culture, strain SH3 degraded 97% of 10 mM phenol in 48 hours. In continuous culture under the conditions of 20 mM of influent phenol concentration and 0.050 hr$^{-1}$ of dilution rate, the treatment rate of phenol was 94%.

• Journal of Environmental Science International
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• v.10 no.5
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• pp.359-364
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• 2001

Pseudomanas sp. EL-04J was previously isolated from phenol-acclimated activated sludge. This bacterium was capable of degrading phenol and cometabolizing trichloroethylene (TCE). After precultivation in the mineral salts medium containing phenol as a sole carbon source, Pseudomonas EL-04J degraded 90% of TCE $25 \mu\textrm{M}$ within 20 hours. Thus, phenol-induced Pseudomonas sp. EL-04J cells can bdegrade TCE. Followsing a transient lag period, Pseudomonas sp. EL-04J cells degraded TCE at concentrations of at least $250 \mu\textrm{M}$ with no apparent retardation in rate, but the transformance capacity of such cells was limited and depended on the cell concentration. The degradation rate of TCE followed the Michaelis-Menten kinetic model. The maximum degradation ratio ($V_{max}$) and saturation constant ($K_{m}$) were $7nmo {\ell}/min{\cdot}mg$ cell protein and $11 \mu\textrm{M}$, respectively. Cometabolism of TCE by phenol fed experiment was evaluated in $50m {\ell}$ serum vial that contained $10m {\ell}$ of meneral sals medium supplemented with $10 \mu\textrm{M}$ TCE degradation was inhibited in the initial period of 1 mM phenol addition, but after that time Pseudomonas sp. EL-04J cells degraded TCE and showed cell growth.

• Korean Journal of Soil Science and Fertilizer
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• v.27 no.4
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• pp.309-314
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• 1994

Population changes of serveral bacterial groups and chemical changes of nutrients applied were compared between soils suspensed with pentachlorophenol(PCP) and amended with different nutrients. The number of total bacteria and Gram-negative bacteria were dramatically increased for 1st week, after remained at its maximum level for a short time, decreased gradually in all treatments for 5th week, the rate of decrease were faster at addition of only PCP than at addition of nutrients and PCP. While, the addition of nutrients in the soil suspension containing PCP suppressed the number of PCP-degrading bacteria. The dissipation of PCP were faster at single addition of PCP than at the combined addition of nutrients with PCP. The nutrients added with PCP were rapidly degraded for 1st week, among the nutrients the rate of degration of glucose was faster than that of glutamic acid or glycine. pH values in the suspension showed which addition of nutrients with PCP caused its changes in comparsion with addition of only PCP where changes was slightly.