• Journal of Soil and Groundwater Environment
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• v.18 no.2
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• pp.10-18
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• 2013

The pilot scale biopile system was designed and operated for evaluation of bioremediation efficiency for petroleum contaminated soil. The pilot scale biopile consisted of biopile dome, aeration system and monitoring system and two biopiles were operated with nutrients and inoculum for more 100 days. The test pile A and B were analyzed with regard to pH, total carbon contents, water contents, nutrients (N, P) and TPH. The initial TPH concentrations for pile A and pile B were about 10,000 mg/kg and 2,300 mg/kg, respectively. After 100 days, the TPH contents decreased about 70% in the pile A and 30% in the pile B. Also, n-$C_{17}$/pristane and n-$C_{18}$/phytane ratios in all pile were significantly changed. The microbial densities in the pile A was increased by approximately $10^7$ CFU/g-soil~$10^8$ CFU/g-soil, but there was almost no changed in the pile B. The average biodegradation rates were calculated about 66.8 mg/kg-day in the pile A and 10.9 mg/kg-day in the pile B. Over the course of operation period, pile temperature was considered the major limiting factor for the efficiency of all biopiles.

• Journal of Soil and Groundwater Environment
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• v.12 no.6
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• pp.70-77
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• 2007

Pseudomonas sp. KM1 was separated from soil contaminated by petroleum and identified. The isolated strain is Gram-positive, rod-shaped and immotile. In batch culture, the optimum cultivation temperature and pH was $35^{\circ}C$ and 7, respectively. Biodegradation of PAHs experiment with soil slurry system was performed using Pseudomonas sp. KM1. Pseudomonas sp. KM1 could degrade 7 PAHs including naphthalene, acenaphthylene, acenaphthene, fluorene, phenanthrene, pyrene, and fluoranthene. These mixed PAHs was easily degraded within one day except fluoranthene, which was degraded much slowly, taking several days by this isolated bacteria. Pseudomonas sp. KM1 is good candidate for bioremediation of PAHs contaminated soils. Biodegradation rates of naphthalene, phenanthrene and pyrene in soils were different at each soil, and the rates were decreased as sorption capacity increased.

• Journal of Soil and Groundwater Environment
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• v.8 no.2
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• pp.44-54
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• 2003

A kinetic model for evaluating effects of surfactant on the biodegradation of HOC(hazardous organic chemicals) in soil-slurry systems was developed. The model includes the partition of HOC and surfactant, the dissolved-, micellar-, and sorbed-phase biodegradation, the enhanced solubilization of HOC by surfactant addition, and the mass transfer of HOC. Phenanthrene as HOC and Trition X-100, Tergitol NP-10, Igepal CA-720, and Brij 30 were used in the model simulations. The biodegradation rate was increased even with a small micellera-phase bioavailability. The biodegradation was not greatly enhanced due to decreased aqueous HOC concentration by increasing surfactant dose in both cases with and without micellar-phase bioavailability. The effect of sorbed-phase biodegradation on total biodegradation rate was not highly important compared to aqueous- and micellar-phase biodegradation. The model can be applied for surfactant screening and optimal design of surfactant-based soil bioremediation process.

• Microbiology and Biotechnology Letters
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• v.34 no.3
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• pp.185-195
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• 2006

Phytoremediation is an economical and environmentally friendly bioremediation technique using plants which can increase the microbial population in soil. Unlike other pollutants such as heavy metals, poly-chlorinated biphenyl, trichloroethylene, perchloroethylene and so on, petroleum hydrocarbons are relatively easily degradable by soil microbes. For successful phytoremediation of soil contaminated with petroleum hydrocarbons, it is important to select plants with high removal efficiency through microbial degradation. In this study, we clarified the roles of plants and rhizobacteria and identified their species effective on phytore-mediation by reviewing the papers previously reported. Plants and rhizobacteria can degrade and remove the petroleum hydrocarbons directly and indirectly by stimulating each other's degradation activity. The preferred plant species are alfalfa, ryegrass, tall fescue, poplar, corn, etc. The microorganisms with a potential to degrade hydrocarbons mostly belong to Pseudomonas spp., Bacillus spp., and Alcaligenes spp. It has been reported that the elimination efficiency of hydrocarbons by soil microorganisms can be improved when plants were simultaneously applied. For more efficient restoration, it's necessary to understand the plant-rhizobacteria interaction and to select the suitable plant and microorganism species.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 1998.11a
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• pp.178-182
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• 1998

Bioremediation techniques have proved to be effective for restoring petroleum-contaminated soils. however some limitations still exist, especially biodegradation of hydrophobic organic compounds(HOCs) in soil is limited by their low solubility and sorption to solid surfaces. The principal objective of this study was to evaluate the effectiveness of biosurfactant sophorolipid on the biodegradation of hydrocarbons in soil. Experimental results showed that sophorolipid was not toxic to the HOC-degrading bacteria and enhanced biodegradation of HOCs in soil better than synthetic surfactants. when these models were treated with 1000mg/soil kg sophorolipid.

• Korean Journal of Soil Science and Fertilizer
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• v.47 no.6
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• pp.391-397
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• 2014

Acid mine drainage occurrence is a serious environmental problem by mining industry; it usually contain high levels of metal ions, such as iron, copper, zinc, aluminum, and manganese, as well as metalloids of which arsenic is generally of greatest concern. It causes mine impacted soil pollution with mining and smelting activities, fossil fuel combustion, and waste disposal. In the present study, three bacterial strains capable of producing urease were isolated by selective enrichment of heavy metal contaminated soils from a minei-mpacted area. All isolated bacterial strains were identified Sporosarcina pasteurii with more than 98% of similarity, therefore they were named Sporosarcina sp. KM-01, KM-07, and KM-12. The heavy metals detected from the collected mine soils containing bacterial isolates as Mn ($170.50mg\;kg^{-1}$), As ($114.05mg\;kg^{-1}$), Zn ($92.07mg\;kg^{-1}$), Cu ($62.44mg\;kg^{-1}$), and Pb ($40.29mg\;kg^{-1}$). The KM-01, KM-07, and KM-12 strains were shown to be able to precipitate calcium carbonate using urea as a energy source that was amended with calcium chloride. SEM-EDS analyses showed that calcium carbonate was successfully produced and increased with time. To confirm the calcium carbonate precipitation ability, urease activity and precipitate weight were also measured and compared. These results demonstrate that all isolated bacterial strains could potentially be used in the bioremediation of acidic soil contaminated by heavy metals by mining activity.

• KSBB Journal
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• v.26 no.1
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• pp.1-6
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• 2011

Contamination of soils, groundwater, air and marine environment with hazardous and toxic chemicals is major side effect by the industrialization. Bioremediation, the application of microorganism or microbial processes to degrade environmental contaminant, is one of the new environmental technologies. Because of low water solubility and volatility of diesel, bioremediation is more efficient than physical and chemical methods. The purpose of this study is biodegradation of diesel in sand by using Rhodococcus fascians, a microorganism isolated from petroleum contaminated soil. This study was performed in the column containing sand obtained from sea sides. Changes in biodegradability of diesel with various flow rates, inoculum sizes, diesel concentrations, and pH were investigated in sand column. The optimal condition for biodegradation of diesel by R. fascians in sand column system was initial pH 8 and air flow rate of 30 mL/min. Higher diesel degradation was achieved at larger inoculum size and the diesel degradation by R. fascians was not inhibited by diesel concentration up to 5%.

• Proceedings of the KSEEG Conference
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• 2002.06a
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• pp.57-79
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• 2002

• Proceedings of the Microbiological Society of Korea Conference
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• 1998.04a
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• pp.52.1-52.1
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• 1998

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 1997.05a
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• pp.120-123
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• 1997

오염토양 복원의 신기술로서 미생물계면활성제를 이용한 생물학적 정화법(Bioremediation)의 표준화된 절차와 현장적용 결과를 제시하였다. 적절한 양분과 수분 그리고 산소를 공급하여 유류 오염물질의 생물학적 제거효율을 극대화시킬 수 있었으며 특히 유류오염물질을 효과적으로 분산시키기 위해 미생물계면활성제를 사용함으로써 오염된 토양을 단기간 내에 복원하는데 상당히 효과적인 기술임을 확인 할 수 있었으며 지속적인 현장적용 기술의 개발을 통하여 국내외적으로 당면하고 있는 토양오염문제를 해결하는데 크게 이바지 할 수 있을 것으로 사료된다.