• Bulletin of the Korean Chemical Society
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• 제23권12호
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• pp.1833-1835
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• 2002

• Journal of Microbiology and Biotechnology
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• 제27권10호
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• pp.1837-1843
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• 2017

Knowledge of avian host responses to brucellosis is critical to understanding how birds resist this infection; however, this mechanism is not well established. On the other hand, temperature has a major involvement in the physiology of living organisms, and cell death induced by heat is attributed to protein denaturation. This study demonstrates the direct bactericidal effect of a high temperature ($41^{\circ}C$) on Brucella abortus that resulted in the gradual reduction of intracellular bacteria and inhibited bacterial growth within avian macrophage HD11 in an increasing period of time. On the other hand, this study also revealed that high temperature does not affect the rate of bacterial uptake, as confirmed by the bacterial adherence assay. No significant difference was observed in the expression of target genes between infected and uninfected cells for both temperatures. This study suggests the susceptibility of B. abortus to bacterial death under a high temperature with an increased period of incubation, leading to suppression of bacterial growth.

• Korean Chemical Engineering Research
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• 제56권4호
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• pp.524-535
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• 2018

본 연구에서는 에멀젼 자기조립틀을 활용하여 거대기공을 갖는 타이타니아 분말을 합성하였으며, 자외선 조사를 활용한 광촉매 실험을 통해 상용화된 타이타니아 나노입자와 다공질 타이타니아 분말을 이용한 고초균의 살균 효과를 비교하였다. 다공질 분말의 기공 크기를 달리하여 자외선 조사 시간에 따른 고초균 수의 감소를 측정하였으며, 살균 실험의 최적 조건을 도출하기 위하여 기공 크기에 따른 다공질 타이타니아 분말의 살균력을 비교하였다. 기공 크기가 작아질수록 살균 효과는 증대됨을 관찰하였으며, 광촉매의 활용 및 자외선 조사에 의해 1시간 동안 50% 이상의 고초균이 제거되는 효과를 확인하였다. 또한 활성 화학종의 발생을 촉진하기 위하여 과산화수소의 희석 용액을 광촉매 살균 방식과 결합하였으며, 1시간 동안의 자외선 조사에 의해 균주의 거의 대부분이 사멸되는 등 고초균에 대한 살균 효과를 증진시킬 수 있었다.

• 한국환경보건학회지
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• 제37권6호
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• pp.482-487
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• 2011

Salmonellosis and brucellosis have caused a considerable danger of farmed animals and economic loss in animal farming industry. In this study, the disinfection efficacy of Citra-Kill$^{(R)}$, a commercial disinfectant, composed to quaternary ammonium chloride and citric acid was evaluated against S. typhimurium and Brucella ovis. A bactericidal efficacy test by broth dilution method was used to determine the lowest effective dilution of the disinfectant following exposure to test bacteria for 30 min at $4^{\circ}C$. Citra-Kill$^{(R)}$ and test bacteria were diluted with distilled water (DW), hard water (HW) or organic matter suspension (OM) according to treatment condition. On OM condition, the bactericidal activity of Citra-Kill$^{(R)}$ against S. typhimurium and Brucella ovis was lowered compared to that on HW condition. As Citra-Kill$^{(R)}$ possesses bactericidal efficacy against animal pathogenic bacteria such as S. typhimurium and Brucella ovis, this disinfectant solution can be used to control the spread of animal bacterial diseases.

• 한국미생물·생명공학회지
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• 제46권1호
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• pp.40-44
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• 2018

Gram 양성세균의 생육을 억제하는 세균을 청주시 무심천 토양에서 분리하였으며, 16S rRNA 유전자 염기서열 분석 결과 Pseudomonas otitidis PS로 동정하였다. PS 균주는 0.5%의 glucose가 포함된 1% soybean meal 배지에서 2차 대사 산물로서 최대 약 0.1%의 수율로 항생물질을 생산하였다. 항생물질 성분은 ethyl acetate로 추출하였으며, Staphylococcus aureus KCTC 1261에 대한 minimum inhibitory concentration은 $2{\mu}g/ml$이었다. 이 성분은 siderophore 활성을 띠어서 chrome azurol S 평판배지에서 주황색 halo를 나타내었으며, 철이 제거되면 생육 억제 효과는 감소하였다. Ascorbic acid 같은 환원제를 첨가하거나 혐기적 환경에서는 항생물질 활성을 잃으므로 PS 항생물질은 활성산소를 방출하여 bactericidal activity를 갖는 것으로 보인다.

• Asian Pacific Journal of Cancer Prevention
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• 제15권3호
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• pp.1299-1306
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• 2014

Background: Nano-biotechnology is recognized as offering revolutionary changes in various fields of medicine. Biologically synthesized silver nanoparticles have a wide range of applications. Materials and Methods: Silver nanoparticles (AgNPs) were biosynthesized with an aqueous extract of Pterocladiella (Pterocladia) capillacea, used as a reducing and stabilizing agent, and characterized using UV-VIS spectroscopy, Fourier Transform Infra red (FT-IR) spectroscopy, transmission electron microscopy (TEM) and energy dispersive analysis (EDX). The biosynthesized AgNPs were tested for cytotoxic activity in a human hepatocellular carcinoma ($HepG_2$) cell line cultured in Dulbecco's modified Eagle medium supplemented with 10% fetal bovine serum, 1% antibiotic and antimycotic solution and 2 mM glutamine. Bacterial susceptibility to AgNPs was assessed with Staphylococcus aureus, Bacillus subtilis [Gram+ve] and Pseudomonas aeruginosa and Escherichia coli [Gram-ve]. The agar well diffusion technique was adopted to evaluate the bactericidal activity of the biosynthesized AgNPs using Ampicillin and Gentamicin as gram+ve and gram-ve antibacterial standard drugs, respectively. Results: The biosynthesized AgNPs were $11.4{\pm}3.52$ nm in diameter. FT-IR analysis showed that carbonyl groups from the amino acid residues and proteins could assist in formation and stabilization of AgNPs. The AgNPs showed potent cytotoxic activity against the human hepatocellular carcinoma ($HepG_2$) cell line at higher concentrations. The results also showed that the biosynthesized AgNPs inhibited the entire panel of tested bacteria with a marked specificity towards Bacillus subtillus. Conclusions: Cytotoxic activity of the biosynthesized AgNPs may be due to the presence of alkaloids present in the algal extract. Our AgNPs appear more bactericidal against gram-positive bacteria (B. subtillus).

• 한국수산과학회지
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• 제48권5호
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• pp.661-667
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• 2015

Vibrio harveyi is one of the most serious pathogens causing vibriosis in larval and grow-out shrimp culture. This study was performed to investigate the bactericidal effect of a monopersulfate compound against V. harveyi and its toxicity in Litopenaeus vannamei. The monopersulfate compound was prepared at 0, 0.15, 0.3, 0.6, 1.2, and 2.4 ppm for the bactericidal efficacy study, and then V. harveyi was added at a rate of 1×10⁶ CFU/mL. Subsequently, five shrimps/dose were added to the water bath. The other groups of shrimp were exposed to monopersulfate, but not to the bacterium. None of the shrimps exposed to any of the monopersulfate treatment doses without bacteria died, and no changes in their movement were detected for 7 days. However, shrimps exposed to bacteria without monopersulfate showed decreased movement and lethargy, but no death. The total number of other bacteria and V. harveyi at the different concentrations decreased significantly by 4-6 log values compared to that in the bacterial control group. The monopersulfate compound completely inhibited V. harveyi growth beginning 1 h after exposure to 2.4 ppm. These results show that the monopersulfate compound is an efficient disinfectant against naturally occurring marine bacteria and V. harveyi without being toxic to shrimp.

• KSBB Journal
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• 제28권6호
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• pp.428-432
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• 2013

The antimicrobial properties of Light-Emitting Diode (LED) are an area of increasing interest. The aim of this study was to evaluate the bactericidal effects of blue (peak at 456 nm), green (peak at 518 nm), red (peak at 654 nm) and blue-green combined (blue 456 nm : green 558 nm = 69:31) LED irradiation to pathogenic bacteria. For this, LED equipment providing power density of $10mW/cm^2$ was installed and plates were exposed to 0.9 or $3.0mW/cm^2$ to irradiate bacteria with 3.2 to $259.2mW/cm^2$ of energy density. As a result, blue and combined LED have shown bactericidal effects on Escherichia coli KCTC 1467 and Listeria monocytogenes ATCC 19115 after irradiation of $3.0mW/cm^2$ for 2 and 4 hr, respectively. Staphylococcus aureus KCTC 1916 was inhibited at 518 nm green LED irradiation. However, red LED irradiation showed no inhibitory effect to the other tested strains. Light technology that utilizes the bactericidal properties of blue (at 456 nm) and blue-green(blue 456 nm : green 558 nm = 69:31) combined LED may have potential applications in the food industry sector.

• 한국식품영양학회지
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• 제13권1호
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• pp.36-44
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• 2000

Survival of pathogenic bacteris(S. aureus, L. monocytogenes, E. coli and S. typhimurium) in tryptic soy broth containing green tea water extract(GTW), green tea ethanol extract(GTE), potassium sorbate (PS) and sodium benzoate(SB) stored at various pH was evaluated. Tryptic soy broth(TSB) containing 0∼2%(w/v) of green tea extracts and preservatives adjusted to pH 5.5, 6.0, 6.5 and 7.0 was inoculated approximately 105 CFU/ml of pathogenic bacteria and incubated at 35$^{\circ}C$ for 24∼48 hours. Survival of bacteria was determined by viable cell counts of bacterial culture at each pH. Minimum inhibitory concentration(MIC) and minimum bactericidal concentration(MBC) of green tea extracts and preservatives against pathogenic bacteria were derived from survival curves of each bacteria. Antibacterial activities of green tea extracts increased with increasing pH but those of preservatives decreased with increrasing pH. S. aureus was the most sensitive strain to GTW and GTE but the most resistant to PS and SB. The MICs of green tea extracts to S. aureus were 0.52∼0.98% at pH 5.5∼6.0 and non inhibitory at pH 7.0. S. typhimurium was the most resistant to green tea extracts while the most sensitive to SB. The MICs of green tea extracts to S. typhimurium were 0.46∼1.62% at pH 5.5∼6.0 and 2% of PS was bactericidal at pH 5.5. 1.0∼2.0% of GTE were bactericidal to all strains tested except L. m9oncytogenes at pH 7.0. GTE was most efficient at inactivating pathogenic bacteria, generally followed by GTW, PS and SB.

• 한국식품위생안전성학회지
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• 제13권4호
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• pp.365-369
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• 1998

가금류 가공등에서 사용이 허가된 Trisodium Phoshate(TSP)와 구강 청결제로 사용되면서 안전한 물질로 알려진 Cetylpyridinium chloride(CPC)를 이용하여 in vitro에서 E. coli O157:H7 및 Listerial monocytogenes에 대하여 살균작용을 조사하였다. E. coli O157:H7 및 Listerial monocytogenes에 대해서는 TSP는 $1{\times}10^{-2}\;M$ 농도에서} $37^{\circ}C$, 30분간 반응으로 각각 30~40%와 40~50%의 살균효과를 보였으며, CPC는 $5{\times}10^{-7}\;M$ 농도에서 $37^{\circ}C$, 30분간 반응으로 각각 90~95%와 95~99%의 살균효과를 보였다. 또한, TSP와 CPC는 온도와 pH에 따라 E.coli O157:H7 및 Listerial monocytogenes에 대한 살균작용이 영향을 받았는데, 온도가 높을수록 두 물질 모두 그 살균 효과 컸으며, TSP는 pH가 높을수록, CPC는 pH가 낮을수록 살균효과가 컸다. 이러한 결과로 보아 TSP와 CPC도 E. coli O157:H7 및 Listerial monocytogenes의 오염방지를 위하여 사용이 가능할 것으로 본다.