• Korean Journal of Microbiology
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• v.46 no.1
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• pp.109-111
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• 2010

Recent studies have described various microorganisms that can degrade PAH, however, there are currently limited methods available to screen for PAH-degrading microorganisms. To screen for PAH-degrading microorganisms, a sublimation method (Alley, Jeremy F. and Lewis R. Brown. 2000. Appl. Environ. Microbiol. 66, 439-442) was modified to produce a simple screening system. In our results, there were several bacterial species capable of pyrene degradation including genera, Coryenbacterium, Gordonia, Rhodococcus, and Streptomyces, which have been screened from 350 bacterial isolates of commercial gasoline and oil-spilled sediment by the sublimation method. The main advantage of this method is that it (i) safely deposits an even, thin and visible layer of PAH onto the agar surface without the use of solvents and (ii) the quantity of PAH sublimed onto the agar can be easily controlled. Overall, this sublimation method may be an effective and simple technique to screen for PAH-degrading microorganisms.

• Proceedings of the KAIS Fall Conference
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• 2005.05a
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• pp.301-302
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• 2005

PAHs의 분해를 위해 Bacillus subtilis 와 Phanerochaete chrysosporium의 두 미생물을 사용하였고, 이들을 부착시킬 담체로 코르크와 톱밥를 선정하여 미생물을 접종시켰다. Phenanthrene 분해의 경우, 반응 초기에는 분해 속도가 매우 빠르지만 반응 12일째 분해 속도가 떨어졌다. 분해 속도는 1)톱밥에 담지한 Bacillus subtilis, 2)코르크에 담지한 Bacillus subtilis, 3)톱밥에 담지한 Phanerochaete chrysosporium, 4)코르크에 담지한 Phanerochaete chrysosporium의 순으로 나타났다.

• Korean Journal of Microbiology
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• v.37 no.2
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• pp.120-123
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• 2001

Sphingomonas chungbukensis DJ77 is able to use phenanthrene and biphenyl as the sole carbon and energy source. Mitomycin C curing experiment suggested that polyaromatic hydrocarbon (PAH) utilization in strain DJ77 was plasmid-encoded. The plasmid cured strains were failed to grow on the minimal medium sprayed with biphenyl or phenanthrene. This was evident from southern hybridizations using a previously cloned DNA segment as a probe. There were positive signals in the palsmid DNA of the wild-type strain DJ77 and the absence of hybridizations with chromosomal DNA from the plasmid DNA of the wild-type strain DJ77 and the absence of hybridizations with chromosomal DNA from the palsmid-cured mutant strains.

• Applied Chemistry for Engineering
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• v.32 no.5
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• pp.581-588
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• 2021

In this study, soil slurry bioreactors were used to treat soils containing 16 polycyclic aromatic hydrocarbons (PAHs) for 35 days. Five different soil samples were taken from manufactured gas plant (MGP) and coal tar disposal sites. Soil properties, such as carbon content and particle distribution, were measured. These properties were significantly correlated with percent biodegradation and degradation rate. The cumulative amount of PAH degraded (P), degradation rate (K_m), and lag phase (𝜆) constants of PAHs in different MGP soils for 16 PAHs were successfully obtained from nonlinear regression analysis using the Gompertz equation, but only those of naphthalene, anthracene, acenaphthene, fluoranthene, chrysene, benzo[k]fluoranthene, benzo(a)pyrene, and benzo(g,h,i)perylene are presented in this study. A comparison between total non-carcinogenic and carcinogenic PAHs indicated higher maximum amounts of PAH degraded in the former than that in the latter owing to lower partition coefficients and higher water solubilities (S). The degradation rates of total non-carcinogenic compounds for all soils were more than four times higher than those of total carcinogenic compounds. Carcinogenic PAHs have the highest partitioning coefficients (K_oc), resulting in lower bioavailability as the molecular weight (MW) increases. Good linear relationships of K_m, 𝜆, and P with the octanol-water partitioning coefficient (K_ow), MW, and S were used to estimate PAH remaining, lag time, and biodegradation rate for other PAHs.

• Journal of Microbiology
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• v.43 no.4
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• pp.319-324
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• 2005

Estuarine sediments are frequently polluted with hydrocarbons from fuel spills and industrial wastes. Polycyclic aromatic hydrocarbons (PAHs) are components of these contaminants that tend to accumulate in the sediment due to their low aqueous solubility, low volatility, and high affinity for particulate matter. The toxic, recalcitrant, mutagenic, and carcinogenic nature of these compounds may require aggressive treatment to remediate polluted sites effectively. In petroleum-contaminated sediments near a petrochemical industry in Gwangyang Bay, Korea, in situ PAH concentrations ranged from 10 to 2,900 ${\mu}g/kg$ dry sediment. To enhance the biodegradation rate of PAHs under anaerobic conditions, sediment samples were amended with biostimulating agents alone or in combination: nitrogen and phosphorus in the form of slow-release fertilizer (SRF), lactate, yeast extract (YE), and Tween 80. When added to the sediment individually, all tested agents enhanced the degradation of PAHs, including naphthalene, acenaphthene, anthracene, fluorene, phenanthrene, fluoranthene, pyrene, chrysene, and benzo [a] pyrene. Moreover, the combination of SRF, Tween 80, and lactate increased the PAH degradation rate 1.2-8.2 times above that of untreated sediment (0.01-10 ${\mu}g$ PAH/ kg dry sediment/day). Our results indicated that in situ contaminant PAHs in anoxic sediment, including high molecular weight PAHs, were degraded biologically and that the addition of stimulators increased the biodegradation potential of the intrinsic microbial populations. Our results will contribute to the development of new strategies for in situ treatment of PAH-contaminated anoxic sediments.

• Journal of Microbiology and Biotechnology
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• v.28 no.2
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• pp.330-337
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• 2018

Polycyclic aromatic hydrocarbons (PAHs), including naphthalene, are widely distributed in nature. Naphthalene has been regarded as a model PAH compound for investigating the mechanisms of bacterial PAH biodegradation. Pseudomonas sp. AS1 isolated from an arseniccontaminated site is capable of growing on various aromatic compounds such as naphthalene, salicylate, and catechol, but not on gentisate. The genome of strain AS1 consists of a 6,126,864 bp circular chromosome and the 81,841 bp circular plasmid pAS1. Pseudomonas sp. AS1 has multiple dioxygenases and related enzymes involved in the degradation of aromatic compounds, which might contribute to the metabolic versatility of this isolate. The pAS1 plasmid exhibits extremely high similarity in size and sequences to the well-known naphthalene-degrading plasmid pDTG1 in Pseudomonas putida strain NCIB 9816-4. Two gene clusters involved in the naphthalene degradation pathway were identified on pAS1. The expression of several nah genes on the plasmid was upregulated by more than 2-fold when naphthalene was used as a sole carbon source. Strains have been isolated at different times and places with different characteristics, but similar genes involved in the degradation of aromatic compounds have been identified on their plasmids, which suggests that the transmissibility of the plasmids might play an important role in the adaptation of the microorganisms to mineralize the compounds.

• Proceedings of the Zoological Society Korea Conference
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• 1996.10a
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• pp.95.2-95
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• 1996

No Abstract, See Full Text

• Korean Journal of Microbiology
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• v.39 no.4
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• pp.267-271
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• 2003

Burkholderia sp. D5, a polyaromatic hydrocarbons(PAHs)-degrading bacterium, was isolated from oil-contaminated soil. The bacterium could utilize phenanthrene (Phe) as a sole carbon source but could not use pyrene (Pyr). However, the strain could degrade Pyr when a cosubstrate such as yeast extract (YE) was supplemented. The PAH degradation rate of the bacterium was enhanced by the addition of other organic materials such as YE, peptone and glucose. YE was a particularly effective additive in stimulating cell growth as well as PAH degradation. When 1 g-YE/L was supplemented into the basal salt medium (BSM) with 215 mg-Phe/L, the specific growth rate (0.28 h-1) and Phe-degrading rate (29.30 μmol/L/h) were enhanced approximately ten and two times more than those obtained in the BSM with 215 mg-Phe/L, respectively. Through kinetic analysis, the maximum specific growth rate (μmax) and PAH degrading rate (Vmax) for Phe were obtained as 0.34/h and 289 ${\mu}mol$/L/h, respectively. Also, μmax and Vmax for Pyr were 0.27 h-1 and 50 ${\mu}mol$/L/h, respectively. The degradation rates for each Phe (2.20 μmol/L/h) and Pyr (2.18 μmol/L/h) were lower in mixture substrates than in a single substrate (29.30 ${\mu}mol$/L/h and 9.58 ${\mu}mol$/L/h, respectively). Burkholderia sp. D5 can degrade Phe and Pyr contained in soil, and the PAH degradation rates in soil were 20.03 ${\mu}mol$/L/h for Phe and 1.09 ${\mu}mol$/L/h for Pyr.

• Journal of Microbiology
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• v.43 no.6
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• pp.572-576
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• 2005

This study focused on detecting catabolic genes for polycyclic aromatic hydrocarbons (PAHs) distributed in the reed rhizosphere of Sunchon Bay, Korea. These marsh and mud environments were severely affected by human activities, including agriculture and fisheries. Our previous study on microbial roles in natural decontamination displayed the possibility that PAH-degrading bacteria, such as Achromobacter sp., Alcaligenes sp., Burkholderia sp. and Pseudomonas sp. play an important decontamination role in a reed rhizosphere. In order to gain further fundamental knowledge on the natural decontamination process, catabolic genes for PAH metabolism were investigated through PCR amplification of dioxygenase genes using soil genomic DNA and sequencing. Comparative analysis of predicted amino acid sequences from 50 randomly selected dioxygenase clones capable of hydroxylating inactivated aromatic nuclei indicated that these were divided into three groups, two of which might be originated from PAH-degrading bacteria. Amino acid sequences of each dioxygenase clone were a part of the genes encoding enzymes for initial catabolism of naphthalene, phenanthrene, or pyrene that might be originated from bacteria in the reed rhizosphere of Sunchon Bay.

• Journal of Life Science
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• v.21 no.11
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• pp.1511-1517
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• 2011

We isolated a potent phenanthrene-degrading bacterium from oil-contaminated soils of Suzhou, China, and assessed the potential use of these bacteria for bioremediation of soils contaminated by polycyclic aromatic hydrocarbons (PAHs) in a microcosm. Based on 16S rDNA sequencing, we identified this bacteria as Sphigobacterium sp. SW-09. By PCR amplification, we also identified catechol 2,3-dioxygenase genes (nahH genes) mediating PAH degradation. Staphylococcus sp. KW-07, which has been identified in our previous study, showed potential for use in bioremediation of oil-contaminated soils. In this experiment, we compared the rate of phenanthrene-degradation between Staphylococcus sp. KW-07 and Sphingobacterium sp. SW-09 in a microcosm condition. Newly isolated Sphingobacterium sp. SW-09 showed a higher phenanthrene-degradation rate than that of Staphylococcus sp. KW-07 in soil microcosms. Together, our results suggest that the Sphingobacterim sp. SW-09 strain isolated from the Suzhou area may also be useful in bioremediation of PAH-contaminated soils.