• Korean Journal of Soil Science and Fertilizer
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• v.42 no.spc
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• pp.1-3
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• 2009

Silver nanoparticles have been used in agricultural practice because of their biocide effect. However, limited information is available for the effect of silver nanoparticles on soil quality. Therefore, the main purpose of this study was to evaluate effect of silver nanoparticle application on soil especially when fertilizer is applied. To simulate potassium fertilizer, potassium chloride was mixed with silver nanoparticles in soil. Concentration of silver and chloride was measured and result showed that concentration of both compounds was decreased at the range of $3.4mg\;kg^{-1}$ and 78-84% respectively after treatment. In addition, analysis of microbial population after treatment showed that microbial population was increased when silver nanoparticles and KCl were mixed. Those results indicated that application of fertilizer has impact on biocide effect of silver nanoparticles in soil.

• Korean Journal of Environmental Agriculture
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• v.20 no.1
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• pp.63-66
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• 2001

To investgate growth effect of tomato by Bacillus sp. WRD-1 isolated from soil, the Bacillus sp. WRD-1 cultures were treated into tomato cultivated soil with different dilutions (1:100, 1:300, and 1:500) and autoclaved Bacillus cultures as control. Growth and yeild of tomato enhanced in treatments of the Bacillus cultures compared to control. The populations of native bacteria and actinomyces were increased twice in field treated with Bacillus sp. WRD-1 cultures, but the number of mold was decreased. Since the Bacillus sp. WRD-1 promoted growth of tomato and affected population dynamics of microorganism in field, this strain is prominent candidate as a microbial biocide to improve soil potential.

• Journal of Microbiology and Biotechnology
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• v.25 no.4
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• pp.511-520
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• 2015

Triclosan, the widely used biocide, specifically targets enoyl-acyl carrier protein reductase (ENR) in the bacterial fatty acid synthesis system. Although the fish pathogen Aeromonas salmonicida subsp. salmonicida exhibits triclosan resistance, the nature of this resistance has not been elucidated. Here, we aimed to characterize the triclosan resistance of A. salmonicida subsp. salmonicida causing furunculosis. The fosmid library of triclosan-resistant A. salmonicida subsp. salmonicida was constructed to select a fosmid clone showing triclosan resistance. With the fosmid clone showing triclosan resistance, a subsequent secondary library search resulted in the selection of subclone pTSR-1. DNA sequence analysis of pTSR-1 revealed the presence of a chromosomal-borne fabV-encoding ENR homolog. The ENR of A. salmonicida (FabVas) exhibited significant homology with previously known FabV, including the catalytic domain YX₍₈₎K. fabVas introduction into E. coli dramatically increased its resistance to triclosan. Heterologous expression of FabVas might functionally replace the triclosan-sensitive FabI in vivo to confer E. coli with triclosan resistance. A genome-wide search for fabVas homologs revealed the presence of an additional fabV gene (fabVas2) paralog in A. salmonicida strains and the fabVas orthologs from other gram-negative fish pathogens. Both of the potential FabV ENRs expressed similarly with or without triclosan supplement. This is the first report about the presence of two potential FabV ENRs in a single pathogenic bacterium. Our result suggests that triclosan-resistant ENRs are widely distributed in various bacteria in nature, and the wide use of this biocide can spread these triclosan-tolerant ENRs among fish pathogens and other pathogenic bacteria.

• Textile Coloration and Finishing
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• v.20 no.3
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• pp.39-56
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• 2008

A wide variety of materials including aldehydes, cationic agents, alcohols, peroxygens, phenols and chlorinated phenols, metal ions are being employed as biocides. Among three levels for biocidal functions (sanitization, disinfection and sterilization), disinfection is an enough level for antimicrobial textiles. In terms of antimicrobial agents for textile applications, quaternary ammonium salts (QAS), chitosan, metal and metal salts, N-halamine based materials are developed with numerous research and the positive ions of those materials may result in disinfection of microorganisms. Photocatalysts, especially titanium dioxide (titania) produces the hydroxyl radical (${\cdot}\;OH$) which causes inactivation of microorganisms after UV radiation, have been used for antimicrobial applications.

• Journal of Environmental Health Sciences
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• v.32 no.5 s.92
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• pp.418-423
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• 2006

이 사례연구는 누수가 있었던 고층 아파트의 공기중 진균 오염 실태를 조사하고, 이를 개선하기 위해 취해진 복원방법의 효과를 평가하기 위해 실시하였다. 공기중 진균은 주로 엔더슨 샘플러를 사용하여 측정하였다. 누수가 있었던 아파트의 복원 전 공기중 진균 농도는 매우 높았다(평균: $51,000\;cfu/m^{3}$, 기하평균: $40,163\;cfu/m^{3}$). 고농도의 오존처리와 오염된 벽체 철거 후 공기중 진균 농도는 상대적으로 매우 낮아졌으며(평균: $1,118\;cfu/m^{3}$, 기하평균: $899\;cfu/m^{3}$), 제거효율은 96.3%로 나타났다. 철거되지 않고 남아 있던 인근 벽체의 벽지를 제거하고 살진균제 처리를 실시한 결과, 공기중 진균 농도는 상대적으로 안전한 수준까지 낮아졌으며(평균: $95\;cfu/m^{3}$, 기하평균: $88\;cfu/m^{3}$), 제거효율은 99.7 %로, 나타났다. 결론적으로, 누수가 있었던 아파트의 공기중 진균 농도는 매우 높은 상태로 오염이 심한 상태이었으나, 본 연구에서 적용한 복원방법들은 공기중 진균 농도 저감에 있어서 매우 높은 효율을 나타냈다.

• Mass Spectrometry Letters
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• v.10 no.4
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• pp.112-116
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• 2019

In this study, a chloroform consumer chemical product (CCP) reference material (RM) is successfully developed, with potential to be used in the proficiency testing of hazardous compounds in CCPs for analysis and testing agencies. Validation experiments are rigorously conducted to evaluate whether the RM meets the requirements set by the ISO 13528 and ISO Guide 35, using a reliable GC/MS method for the analysis of chloroform. The obtained calibration plot linearity, limit of detection (LOD), and limit of quantitation (LOQ) are excellent. The developed RM meets the homogeneity and stability requirements; the between-unit (s_bb) and within-unit (s_wb) standard deviations are less than 2.5%, and the stability is found to be guaranteed for 50 days.

• 보존과학연구
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• s.28
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• pp.59-73
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• 2007

Wooden artifacts are biologically damaged by animals, insects, and micro-organisms. We focused on the evaluation of the antifungal and insecticidal activities of tree extracts to control deterioration of wooden cultural properties. 12 kinds of methanol extracts from 9 species of tree were investigated for their biocidal activities against two micro-organisms and two spices of insect. Most tree extracts showed fungicidal activities to Tyromyces palustris and Trametes versicolor. Among 12 different tree extracts, the strongest antifungal activity against T.palustris and T.versicolor was observed from the extracts of Pinus densiflora stem-bark extract and Pinus koraiensis leaf extracts. However, in the insecticidal activity test, Pinus densiflora stem-bark extracts against termite was relatively effective. Chemical compositions of methanol extracts were analyzed by gas chromatography/mass spectrometry. As a result, it was confirmed that development of biocide based on the natural extracts can be expected to conservate of wooden cultural properties.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.11a
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• pp.170-172
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• 2013

To be applied to a humid environment such as bathroom and kitchen, sealant should have good adhesion, tensile strength, etc., it also have the resistance to fungal contamination from the environment. It is important to select right material for sanitary sealing application in order to prevent premature discoloration and fungal activities. Especially for high humidity conditions, it is crucial to have longer mildew and fungal resistance. In this article, we intended to give guide lines for developing right sanitary sealing material and practical test method for evaluating anti-fungal performances reflecting Korean residential life style.

• Journal of Conservation Science
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• v.33 no.4
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• pp.255-266
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• 2017

Chemically derived pesticides have been used to prevent biological damage to domestic cultural property. However, their use is gradually being restricted due to the harmful effects on the human body and environment. Therefore, there is a growing interest in the search for new antifungal biopharmaceuticals whose safety has been confirmed by toxicity evaluation through animal experiments. This paper presents methods of toxicity evaluation of natural biocides using Sprague-Dawley rats and New Zealand White (NZW) rabbits. Safety of the natural biocide extract of Asarum sieboldii was evaluated using single-dose oral and dermal toxicity tests in Sprague-Dawley rats, and eye and skin irritation tests in NZW rabbits. The extract has proven antimicrobial and insecticidal activities against wood-rotting fungi and termites. After single oral administration to rats, the $LD_{50}$ values were determined to be over 4,000 and 2,000 mg/kg for males and females, respectively. After single dermal administration to rats, the $LD_{50}$ values exceeded 10,000 mg/kg for both males and females. The extract was identified to be non-irritant to the rabbit eye, and only slightly irritant to the rabbit skin. In this study, we confirmed the safety of the A sieboldii extract through animal testing. Due to the harmfulness of humidifier disinfectants, focus is on the safety of chemical pesticides, and toxicity evaluation is suggested as the basic method for hazard evaluation.

• Parasites, Hosts and Diseases
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• v.36 no.1
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• pp.7-14
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• 1998

In order to understand the action mechanism of polyhexamethylene biguanide (PHMB) to the cyst of Accnthcnloebc on the morphological basis, the cysts of four corneal isolates of Acanthanoebc were treated with minimal cysticidal concentration (MCC) of PHMB and their ultrastructural changes were examined by transmission electron microscopy. The most striking change of cysts treated with PHMB compared with normal cysts was the shrinkage of intracystic amoebae, which resulted in the separation of the plasma membrane of intracystic amoeba from endocystic wall. Subplasmalemmal lipid droplets became irregularly shaped . In severely damaged cysts, cytoplasm was aggregated and organelles were severely deformed. Cytoplasmic materials were leaked out through the damaged plasma membrane. Most cysts showed aggregation of nuclear chromatin material. Number of mitochondrial cristae was also reduced. Ecto- and endo-cystic walls were relatively well tolerated. Findings in the present study revealed that PHMB affected mainly on plasma membrane, but lesser on organellar membrane of intracystic amoeba. It seemed likely that PHMB might kill cystic forms of Accnthamoebc by similar mechanism in which this environmental biocide can damage the cell wall of Escherichia coli by binding with acidic phospholipids.