• Toxicological Research
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• 제27권4호
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• pp.241-246
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• 2011

To obtain soil microorganisms producing antimigratory activity which is important in controlling the metastasis of cancer cells, more than three hundreds of soil microbes were isolated from sixteen soil sources including Namsan mountain and designated as DGU1001-10338. At first, their antibiotic activities were examined by paper-disc method. More than 40 soil microbes produced compounds with antibiotic activity. Then, antimigratory activities of selected soil microorganisms were examined in a sphingosylphosphorylcholine-induced migration assay in PANC-1 cells. Six of 42 soil microorganisms having antibacterial activity also had more than 45% inhibitory activity on migration of PANC-1 cells. These results suggested that selected soil microorganisms were a useful starting point to find compounds for controlling metastasis of cancer cells.

• 한국식품영양과학회지
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• 제26권6호
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• pp.1258-1267
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• 1997

Corbon dioxide id effective for extending the shelf-life of perishable foods by retarding microbial growth. The overall effect of carbon dioxide is to increase both the lag phase and generation time of microorganisms. However, the role of carbon dioxide in affecting the growth and metabolism of any given microorganisms is not clear yet, although its inhibitory effect is generally found at moderate to high concentrations. Systematic studies of the effects of carbon dioxide on microorganisms are therefore warranted. It is also necessary to understand the role of carbon dioxide in the preservation of foods as well as the control by carbon dioxide of fermentations of biotechnological importance. In this review, the antimicrobial effect of carbon dioxide on microorganisms is investigated in terms of its gas and solution properties, inhibition of microbial growth and specific metabolic processes, perturbation of membrane structure.

• Journal of Microbiology and Biotechnology
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• 제8권2호
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• pp.101-110
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• 1998

The extent of biological diversity being revealed by molecular techniques accentuates the need to develop methods to isolate and culture the large numbers of microorganisms that remain to be studied. The discovery and characterization of novel microorganisms will provide information useful in understanding microbial ecosystems and have the potential to lead to new products for the biotechnology industry. In this review, the use of innovative techniques and exploration of unusual ecosystems, that have begun to address the challenge of isolating the "uncultured" members of the microbial population, are examined.

• 한국농공학회지
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• 제45권7호
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• pp.94-106
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• 2003

A pilot study was performed to examine the feasibility of UV disinfection system and the reactivation of indicator microorganisms (TC, FC, E. coli) after UV irradiation for agricultural reuse of reclaimed water. Photoreactivation and dark repair enable UV-inactivated microorganisms to recover and may reduce the efficacy of UV inactivation, which might be drawbacks of the UV disinfection method. The effluent of biofilter for 16-unit apartment house was used as input to the UV disinfection system, and average SS and BOD concentration were 3.8 and 5.7 mg/L, respectively, and the mean level of total coliform was in the range of $1.0\times10^4$ MPN/100mL. UV disinfection was found to be effective and it reduced mean concentration of indicator microorganisms (total coliform, fecal coliform, and E. coli) to less than 100 MPN/100mL within 60s exposure using 17, 25, and 40W lamps. Two UV doses of 6 and 16 mW$\cdot$s/$\textrm{km}^2$ were applied and microorganisms reactivation was monitored under the dark, photoreactivating light, and solar irradiation. Microorganisms reactivation was observed in the UV dose of 6 mW$\cdot$s/$\textrm{km}^2$, and numbers increased up to 5% at the photoreactivating light and 1% at the dark. However, microorganisms were inactivated rather than reactivated at the solar radiation and numbers decreased to non-detectible level about below 2 MPN/100mL in 4 hours. In the case of 16 mW$\cdot$s/$\textrm{km}^2$, microorganism reactivation was not observed indicating that UV dose might affect the reactivation process such as photoreactivation and dark repair. Therefore, concerns associated with microorganism reactivation could be controlled by sufficient UV dose application. Agricultural reuse of reclaimed water might be even less concerned due to exposure to the solar irradiation that could further inactivate microorganisms. The pilot study result is encouraging, however, sanitary concern in water reuse is so critical that more comprehensive investigation is recommended.

• 한국식품영양학회지
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• 제16권3호
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• pp.180-186
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• 2003

가열살균 처리시의 온도값을 이용하여 다양한 미생물들의 가열살균 효과를 D값, z값 등의 미생물 내열성 특성치와 kinetic 모델 및 수식을 이용하여 살균치 계산을 컴퓨터를 이용하여 수행함으로써 target 미생물의 살균정도를 예측하고자, Excel과 Visual Basic을 연동하여 작성된 시스템으로 Excel을 기본으로 사용한 프로그램을 개발하였다. 가열살균 target 미생물을 선택하고자 야채식품을 기반으로 하는 식품에서의 미생물을 검토하여, 내열성인 가장 큰 호기성 포자형성균인 Bacillus spp. 계통이 산을 형성하여 맛 등의 품질을 저하시켜 변패를 유발하며, 위생적인 면에서 포자수를 줄이거나 사멸할 필요가 있어서 선택하였다. 병원성 균 중에서 $D_{121.1}$이 0.0065분, z값이 7.8$^{\circ}C$인 Bacillus cereus와 부패현상 관련 균 중에서 $D_{121.1}$이 0.5분, z값이 12$^{\circ}C$인 Bacillus subtilis를 대상으로 해서 개발되었으며, 필요시에는 D값과 z값을 직접 대입하므로서, 여러 가지 미생물에 대해서도 적용이 가능하게 하였다.

• 한국미생물·생명공학회지
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• 제42권3호
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• pp.293-296
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• 2014

본 논문에서는 극지미생물의 저온 활성 protease 생산에 관한 연구를 수행하였다. 먼저 protease를 생산하는 극지미생물인 PAMC 25641, 25614, 25719, 25617을 16s rDNA 염기서열 분석을 이용하여 동정하였다. 그 후, 다양한 온도($5^{\circ}C$, $10^{\circ}C$, $15^{\circ}C$, $20^{\circ}C$)에서의 성장률 및 protease activity, specific activity를 확인하였다. 각 미생물의 온도별 성장률은 대체로 비슷한 경향을 보였으나 25617은 $20^{\circ}C$에서 급격한 성장률 증가를 확인할 수 있었다. 또한, specific activity는 25641이 5, 15, $20^{\circ}C$에서 가장 높은 specific activity를 갖는 것을 확인하였다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제21권1호
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• pp.72-79
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• 2016

Bioremediation is one of the most effective ways to remediate TPH-contaminated sites. However, under actual field conditions that are not at the optimum temperature, degradation of microorganisms is generally reduced, which is why the efficiency of biodegradation is known to be significantly affected by the soil temperature. Therefore, in this study, the labscale experiment was conducted using indigenous crude oil degrading microorganisms isolated from crude oil contaminated site to evaluate the remediation efficiency. Crude oil degrading microorganisms were isolated from crude oil contaminated soil and temperature, which is a significant factor affecting the remediation efficiency of land farming, was adjusted to evaluate the microbial crude oil degrading ability, degradation time, and remediation efficiency. In order to assess the field applicability, the remediation efficiency was evaluated using crude oil contaminated soil (average TPH concentration of 10,000 mg/kg or more) from the OO premises. Followed by the application of microorganisms at 30℃, the bioremediation process reduced its initial TPH concentration of 10,812 mg/kg down to 1,890 mg/kg in 56 days, which was about an 83% remediation efficiency. By analyzing the correlation among the total number of cells, the number of effective cells, and TPH concentration, it was found that the number of effective microorganisms drastically increased during the period from 10 to 20 days while there was a sharp decrease in TPH concentration. Therefore, we confirmed the applicability of land farming with isolated microorganisms consortium to crude oil contaminated site, which is also expected to be applicable to bioremediation of other recalcitrant materials.

• 식물병연구
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• 제28권4호
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• pp.195-203
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• 2022

Zea mays, known as maize or corn, is a major staple crop and an important source of energy for humans and animals, thus ensuring global food security. Approximately 9.4% of the loss of total annual corn production is caused by pathogens including fungi, bacteria, and viruses, resulting in economic losses. Although the use of fungicides is one of the most common strategies to control corn diseases, the frequent use of fungicides causes various health problems in humans and animals. In order to overcome this problem, an eco-friendly control strategy has recently emerged as an alternative way. One such eco-friendly control strategy is the use of beneficial microorganisms in the control of plant pathogens. The beneficial microorganisms can control the plant pathogens in various ways, such as spatial competition with plant pathogens, inhibition of fungal or bacterial growth via the production of secondary metabolites or antibiotics, and direct attack to plant pathogens via enzyme activity. Here, we reviewed microorganisms as biocontrol agents against corn diseases.

• Environmental Engineering Research
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• 제7권2호
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• pp.67-73
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• 2002

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.110.3-111
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• 2003

The effect of biological control on the severity of hot pepper wilt disease was evaluated in the vinyl house with plants cultivated in the nursery soil containing chitin and chitinolytic microorganisms. The chitinolytic microorganisms, Trichoderma harzianum and Chromobacterium sp. strain C-61, were well survived in the nursery soil containing chitin. The hot pepper damping-off was markedly suppressed in the nursery soil containing chitin and chitinolytic microorganisms. The survival of chitinolytic microorganisms and suppression of damping-off were superior as the amounts of chitin added to the nursery soil increased, but growth of hot pepper was inhibited in the 10％ (w/w) chitin treatment. When the plants cultivated in the nursery soil containing 1％ chitin and chitinolytic microorganisms were transplanted in the vinyl house, the vegetative growth increased and the wilt disease was reduced as comparison with those of control.