• Microbiology and Biotechnology Letters
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• v.35 no.1
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• pp.58-65
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• 2007

The role of soil microorganisms, specifically rhizobacteria, in the development of rhizoremediation techniques is important to speed up the process and to increase the rate of mobilization or absorption of heavy metals to the plant. In this study, Methylobacterium sp. SY-NiR1 was isolated from the rhizosphere soils of plants in oil and heavy metal-contaminated soil. Based on its pink pigmented colony, rod-shape cells, and belonging in $\alpha-Proteobacteria$, Methylobacterium sp. SY-NiR1 is considered a pink-pigmented facultative methylotroph. SY-NiR1 had the ability to produce indole acetic acid which is one of phytohormones. This bacterium showed resistance against multiple heavy metals such as Cd, Cr, Cu, Pb, Ni, Zn, and the order of its resistance based on $EC_{50}$ was Zn > Ni > Cu > Pb > Cd > Cr. Therefore, Methylobacterium sp. SY-NiR1 can stimulate seed germination and plant growth in soil contaminated with heavy metals.

• KSBB Journal
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• v.17 no.1
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• pp.38-43
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• 2002

Characteristics of cell growth and heavymetal adsorption by recombinant Saccharomyus cerevisiae strains harboring multiple copies of the CUP1 gene encoding metallothione (MT) protein were studied in batch cultures. Recombinant S. cerevisiae strains harboring multiple copies of the CUP1 gene were superior to the host and wild-type yeast strains in terms of cell growth and heavy metal removal, indicating that the copy number of the CUP1 gene for MT expression played an important role in the adsorption of heavy metals. It was suggested that the CUP1 promoter for the MT expression is induced by manganese and zinc as well as copper An optimum copper concentration for MT expression and concomitant adsorption of heavy metals by recombinant S. cerevisiae was found to be 0.31 mM. A nonionic surfactant Triton X-100 enhanced cell growth by 17.7% and removal of zinc by 6.1% compared with the control case.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2000.05a
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• pp.245-246
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• 2000

콩과식물인 전동싸리를 대상으로 통제된 조건하에서 Al과 Co처리에 따른 식물체의 생장반응과 식물체내 중금속의 축적정도 및 근류의 질소고정 활성의 변화를 조사한 결과 중금속은 Co가 Al보다 높게 축적되었고, 처리 초기에는 지하부를, 장기간 처리시는 광합성 기관의 생장을 억제했는데, Co 처리는 영향이 미약하였으나, Al처리구는 다소 심각한 영향을 주었으며, 생장에 비해 질소고정계의 피해가 현저하였다. 전동싸리는 흡수된 중금속을 뿌리수준에서 조절함으로써 광합성기관으로 이동을 억제하는 중금속에 대한 생장적응을 나타내었다. 결국 전동싸리는 30ppm의 중금속 처리시 뿌리 수준에서 조절함으로써 광합성기관으로 전이를 차단하여 금속에 대한 내성 나타내었고, Al이 Co보다 심각한 영향을 미치는 것으로 나타났다.

• Korean Journal of Environmental Biology
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• v.22 no.3
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• pp.394-399
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• 2004

A BOD sensor was prepared with S. marcescens LSY4 and was applied for measurement of BOD values of a solution containing the standard organic pollutants. The sensor sensitivity was nearly independent of the culture time in the range of 9-16 hours. It was also affected little by the cell mass in the range of 0.22-0.75 mg $cm^{-2}$. A cyclic change in the solution pH in the range of 4-9 was accompanied by a reversible variation in the sensor sensitivity. However, the reversibility was lost when the solution pH became more acidic or more basic. Heavy metal ions lowered the sensor sensitivity, which took place more precipitously in the presence of $Cu^{2+}$ and $Ag^+$ rather than in the presence of $Zn^{2+}$ and $Cd^{2+}$. The reduction of the sensor sensitivity was significantly attenuated by loading heavy metal ion tolerance induced strain. The $Cu^{2+}$tolerance induced strain was more efficient for the attenuation than $Zn^{2+}$ and $Cd^{2+}$ tolerance induced strain.

• Korean Journal of Environmental Agriculture
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• v.17 no.3
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• pp.246-253
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• 1998

Heavy metal-tolerant microorganisms, such as Pseudomonas putida, P. aeruginosa, P. chlororaphis and P. stutzeri which possessed the ability to accumulate cadmium, lead, zinc and copper, respectively, were isolated from industrial wastewaters and mine wastewaters polluted with various heavy metals. The binding sites of heavy metal in the cells were investigated by chemical modification of functional groups the cell walls. To determine the binding sites of heavy metal in the cells, electrochemical charge of amine and carboxyl groups in the cell walls of heavy metal-tolerant microorganisms were chemically modified. Chemical modifications of amine groups did not affect the heavy metal uptake as compared to native cell walls. In contrast, modifications of carboxyl groups drastically decreased heavy metal uptake as compared to native cell walls, and electron microscopy confirmed that the form and structure of the heavy metal uptake were different from those of native cell walls. The results suggested that the carboxyl groups were the major sites of heavy metal uptake in the heavy metal-tolerant microorganism cell.

• Microbiology and Biotechnology Letters
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• v.20 no.6
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• pp.693-698
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• 1992

The resistant effect of several heavy metal ions to Serratia marcescens strain P was studied by the method of minimal inhibitory concentration(MIC), and testing for their metal biosorption. S. marcescens strain P showed a good survival in the presence of high concentrations of some metal ions, namely cadmium, lead, iron, magnesium, and manganese. Copper had the most inhibitory effect among tested. The MIC value was ranged from 0.79 to 1.58 mM. Cells of S. marcescens strain P exhibit an abnormally long lag phase when incubated in high concentrations of zinc and cadmium. Pigment production was reduced by zinc and cadmium, but enhanced by lead and iron. S. marcescens strain P was resistant to ampicillin, tetracycline, cefamandole and chloramphenicol with minimal inhibitory concentration of 128 $\mu$g/ml, 32 $\mu$g/ml, 256 $\mu$g/ml, and 8 $\mu$g/ml, respectively. The kinetics study of biosorptive uptake by S. marcescens strain P revealed that 16.59% of cadmium and 35.38% of lead were eliminated from the media.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2004.05a
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• pp.255-257
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• 2004

오염 토양 개선사업이 완료된 밀양시 구운동 광산의 이.화학적 성분을 기초로 하여 비경작지의 일부 야생식물 중 축적된 중금속 함량을 분석한 결과, 토양의 각 지점별 평균 함량은 유기물 13.18g/kg, 유효인산 40.65mg/kg, 석회 5.06, 칼슘 6.85, 고토 1.94cmol/kg으로서 우리나라 밭 토양의 평균보다 낮았고 중금속 함량은 아연(Zn)이 평균 383.1mg/kg, 구리(Cu) 135.2mg/kg, 납(Pb) 105.4mg/kg로 조사되었다. 조사 지점 중 광미의 퇴적으로 인한 오염이 있는 광산 위 st. 3에서 아연(945mg/kg)과 구리(535mg/kg)의 함량이 가장 높았고 다음이 광미가 많이 잔재하고 있는 광구 앞인 st. 4였으며 이곳은 납(289.5mg/kg)의 함량이 가장 높은 지점이었다. 식물체 내의 중금속 함량은 차즈기>쑥>억새>싸리 순이었고 특히 차즈기의 경우는 다량의 중금속이 축적되어 있어 중금속 오염 지역에 대한 내성이 있는 지표종으로 추측되어 이에 대한 중금속 축적 능력 확인 실험이 필요할 것으로 판단된다.

• Korean Journal of Plant Resources
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• v.24 no.1
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• pp.48-54
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• 2011

This study was performed to analyze the possibility of using Korean native Aster koraiensis Nakai for phytoremediation at various fields. A. koraiensis was cultivated at paddy, upland and forest soils contaminated with heavy metals. After 8 weeks of cultivation, and growth and its absorbing capacity of heavy metals were analyzed. The results showed that A. koraiensis was grown well even at the soil highly contaminated with heavy metals, which means it has a tolerance to heavy metals. As analysis results of arsenic, cadmium, copper, lead and zinc contents absorbed from various soils contaminated with heavy metals, heavy metal absorbing capacity of A. koraiensis was depending on the heavy metal contents in the soils and soil property. In case of arsenic, cadmium and copper, heavy metal accumulation capacities of Aster koraiensis were much influenced by contents of heavy metals in the soils. Absorbing capacity of plants was increased when heavy metal contents in the soils were high. Lead absorbing capacity was depending more on soil property than lead contents in the soil, and was great at sandy soil of forest. Zinc absorbing capacity was influenced by both soil properties and Zn contents in the soil, was increased at paddy soil contaminated with high concentrations of heavy metals and upland soils. In general, A. koraiensis had a tolerance to heavy metals and showed great absorbing capability of heavy metals. So A. koraiensis can be used as a good landscape material for phytoremediation at various soils contaminated with heavy metals.

• Proceedings of the Zoological Society Korea Conference
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• 1994.10a
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• pp.201.1-201
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• 1994

• Proceedings of the Zoological Society Korea Conference
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• 1994.10a
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• pp.91.2-91
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• 1994