• Journal of Microbiology and Biotechnology
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• v.14 no.2
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• pp.324-329
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• 2004

Oxygen diffuses through the cation-specific membrane, reducing the coulomb yield of the fuel cell. In the present study, attempts were made to enhance current generation from the fuel cell by lowering the oxygen diffusion, including the uses of ferricyanide as a cathode mediator and of a platinum-coated graphite electrode. Ferricyanide did not act as a mediator as expected, but as an oxidant in the cathode compartment of the microbial fuel cell. The microbial fuel cell with platinum-coated graphite cathode generated a maximum current 3-4 times higher than the control fuel cell with graphite cathode, and the critical oxygen concentration of the former was 2.0 mg $1^{-1}$, whilst that of the latter was 6.6 mg $1^{-1}$. Based on these results, it was concluded that inexpensive electrodes are adequate for the construction of an economically feasible microbial fuel cell with better performance as a novel wastewater treatment process.

• Journal of Microbiology and Biotechnology
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• v.15 no.1
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• pp.192-196
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• 2005

Abstract Oligotrophic microbial fuel cells (MFCs) were tested for the continuous monitoring of low biochemical oxygen demand (BOD) by using artificial wastewater, containing glucose and glutamate, as check solution. Ten times diluted trace mineral solution was used to minimize the background current level, which is generated from the oxidation of nitrilotriacetate used as a chelating agent. The feeding rate of 0.53 ml/min could increase the sensitivity from 0.16 to 0.43 ${\mu}$A/(mg BOD/l) at 0.15 ml/min. The dynamic linear range of the calibration curve was between 2.0 and 10.0 mg BOD/l, and the response time to the change of 2 mg BOD/l was about 60 min. The current signal from an oligotroph-type MFCs increased with the increase in salts concentration, and the salt effect could be eliminated by 50 mM phosphate buffer.

• Journal of Microbiology and Biotechnology
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• v.15 no.2
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• pp.438-441
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• 2005

A mediator-less microbial fuel cell (MFC) was used to determine the performance effects of a membrane­electrode assembly (MEA). The MFC with an MEA generated a higher current with an increased coulomb yield when compared to an MFC with a separate cathode. Less oxygen was diffused through an MEA than through a Nafion membrane. The MFC performance was improved with a buffer, although a high-strength buffer reduced the performance.

• Journal of Microbiology and Biotechnology
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• v.16 no.2
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• pp.163-177
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• 2006

• Journal of Microbiology and Biotechnology
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• v.16 no.9
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• pp.1481-1484
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• 2006

In this study, glucose and glutamate (copiotrophic conditions) were used to enrich electrochemically active bacteria (EAB) in a microbial fuel cell (MFC). The enriched population consisted primarily of ${\gamma}$-Proteobacteria (36.5%), followed by Firmicutes (27%) and O-Proteobacteria (15%). Accordingly, we compared our own enrichments done under many different conditions with those reported from the literature, all of which support the notion that electrochemically active bacteria are taxonomically very diverse. Enrichments with different types and levels of energy sources (fuels) have clearly yielded many different groups of bacteria.

• Journal of Soil and Groundwater Environment
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• v.18 no.3
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• pp.73-81
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• 2013

Various remediation methods have been applied to clean soils contaminated with pollutants. They remove contaminants from the soils by utilizing physicochemical, biological, and thermal processes and can satisfy soil remediation standards within a limited time; however, they also have an effect on the biological functions of soils by changing soil properties. In this study, changes of the biological properties of soils before and after treatment with three frequently used remediation methods-soil washing, land farming, and thermal desorption-were monitored to investigate the effects of remediation methods on soil biological functions. Total microbial number and soil enzyme activities, germination rate and growth of Brassica juncea, biomass change of Eisenia andrei were examined the effects on soil microorganisms, plant, and soil organisms, respectively. After soil washing, the germination rate of Brassica juncea increased but the above-ground growth and total microbial number decreased. Dehydrogenase activity, germination rate and above-ground growth increased in both land farming and thermal desorption treated soil. Although the growth of Eisenia andrei in thermal desorption treated soil was higher than any other treatment, it was still lower than that in non-contaminated soil. These results show that the remediation processes used to clean contaminated soil also affect soil biological functions. To utilize the cleaned soil for healthy and more value-added purposes, soil improvement and process development are needed.

• Proceedings of the Microbiological Society of Korea Conference
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• 2003.05a
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• pp.103-104
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• 2003

• Proceedings of the Microbiological Society of Korea Conference
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• 2005.05a
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• pp.189.3-189
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• 2005

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.04a
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• pp.39-42
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• 2004

Landfarming and a microbial agent, Bioil-D, were used to treat diesel-contaminated soil. The microbial agent was applied to the contaminated soil in a concentration of 5$\times$10$^2$ cfu/soil(g) and the total amount of microbial agent, 210$\ell$, was sprinkled on the soil four times for 24 days during 50 day-remediation period. The remediation goal, lower than 800mg/kg of TPH, was achieved from 5, 707 mg/kg of TPH within 50 days. The total number and activity of indigenous microorganisms were increased by 100 times after the microbial agent, Bioil-D, was applied to the contaminated soil.

• Bulletin of Korea Environmental Preservation Association
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• v.26 no.5_6
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• pp.59-61
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• 2004

Landfarming and a microbial agent were used to treat dilsel-contaminated soil. The microbial agent was applied to the contaminated soil in a concentration of 5$\times$102 cfu/soil(g) and the total amount of microbial agent, 210 l , was sprinkled on the soil four times for 24 days during 50 day-remediation period. The remediation goal, lower than 800mg/kg of TPH, was achieved from 5,707mg/kg of TPH within 50 days. The total number and activity of indigenous microorganisms were increased by 100 times after the microbial agent, Bioil-D, was applied to the contaminated soil.