• Bulletin of the Korean Chemical Society
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• 제33권8호
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• pp.2592-2596
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• 2012

Cysteine capped silver nanoparticles (Cys-AgNPs) have been synthesized by employing electrochemically active biofilm (EAB), $AgNO_3$ as precursor and sodium acetate as electron donor in aqueous solution at $30^{\circ}C$. Cys-AgNPs of 5-10 nm were synthesized and characterized by UV-Vis, FT-IR, XRD and TEM. Capping of the silver nanoparticles with cysteine provides stability to nanoparticles by a thiolate bond between the amino acid and the nanoparticle surface and hydrogen bonding among the Cys-AgNPs. In addition, the antibacterial effects of as-synthesized Cys-AgNPs have been tested against two pathogenic bacteria Escherichia coli (O157:H7) and Pseudomonas aeruginosa (PAO1). The results demonstrate that the as-synthesized Cys-AgNPs can proficiently inhibit the growth and multiplication of E. coli and P. aeruginosa.

• KSBB Journal
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• 제22권6호
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• pp.438-442
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• 2007

본 연구는 3-전극계와 전기화학적 활성미생물 (EAB)을 이용한 BOD 측정용 바이오센서의 개발에 대한 것이다. 바이오센서의 측정능력 조사를 위하여, 인공폐수 및 실제폐수가 사용되었다. 폐수 시료의 유입조건은 유입속도 2 mL/min, 유입시간 10분, 유입간격은 50분으로 설정하였고, EAB의 전자수용체로 정전압이 적용된 작업전극을 사용하였으며 이때, 정전압기 (potentiostat)를 이용하여 +0.7 V를 인가하여 주었다. 인공폐수와 실제폐수를 이용한 BOD 측정의 정확성 분석결과, BOD 변화에 대해 발생전류 역시 비례적으로 변화하는 것을 확인하였으며 각각 0.99 및 0.98의 높은 상관계수 (BOD vs. Coulombic yield, $BOD_5$ vs. Coulombic yield)를 가지는 것을 확인하였다. BOD (혹은 $BOD_5$) 변화에 대한 반응시간은 30분 이내로 확인되어 실시간 측정에 적합함을 확인할 수 있었다. 이러한 결과들을 토대로 EAB 및 3-전극계를 이용한 폐수의 BOD 측정용 센서의 구성이 가능함을 확인하였다.

• Journal of Microbiology and Biotechnology
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• 제16권9호
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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 Microbiology and Biotechnology
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• 제16권2호
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• pp.163-177
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• 2006

• 한국물환경학회지
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• 제26권4호
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• pp.608-613
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• 2010

Electricity generation of microbial fuel cells (MFC) is greatly affected by the kind of feed substrates because substrates would change microbial community of electrochemically active bacteria (EAB) able to transfer electrons to electrode. The effect of different substrates on electricity generation and microbial community of MFC was investigated. Two-chamber MFCs fed with acetate (A-MFC), butyrate (B-MFC), propionate (P-MFC), glucose (G-MFC) and a mixture (M-MFC) of the 4 substrates (acetate : butyrate : propionate : glucose = 1 : 1 : 1 : 1 as $COD_{Cr}$ base) were operated under continuous mode. The maximum power density was found from the M-MFC ($190W/m^3$) which showed the lowest internal resistance ($89{\Omega}$). The maximum power densities of the pure substrates feed MFCs were in order of A-MFC ($25W/m^3$), P-MFC ($21W/m^3$), B-MFC ($20W/m^3$) and G-MFC ($9W/m^3$). In DGGE analysis, the microbial community structure in suspension was quite different from each others depending on feed substrates, while the community structure in the biofilm was relatively similar regardless of the substrates. This result suggests that the feed substrates would affect the microbial community of suspended growth bacteria than attached growth bacteria resulting in difference of electricity generation in MFCs.