• The Plant Pathology Journal
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• 제32권2호
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• pp.157-161
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• 2016

Gamma irradiation was evaluated for its in vitro and in vivo antibacterial activity against a postharvest bacterial pathogen, Erwinia carotovora subsp. carotovora (Ecc). Gamma irradiation in a bacteria cell suspension resulted in a dramatic reduction of the viable counts as well as an increase in the amounts of DNA and protein released from the cells. Gamma irradiation showed complete inactivation of Ecc, especially at a dose of 0.6 kGy. In addition, scanning electron microscopy of irradiated cells revealed severe damage on the surface of most bacterial cells. Along with the morphological changes of cells by gamma irradiation, it also affected the membrane integrity in a dose-dependent manner. The mechanisms by which the gamma irradiation decreased the bacterial soft rot can be directly associated with the disruption of the cell membrane of the bacterial pathogen, along with DNA fragmentation, results in dose-dependent cell inactivation. These findings suggest that gamma irradiation has potential as an antibacterial approach to reduce the severity of the soft rot of paprika.

• 미생물학회지
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• 제28권3호
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• pp.204-209
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• 1990

1987년 9월부터 1988년 8월까지 소양호 4개 정점에서 총 세균수, 종속영양세균수의 분포와 각 종의 alkaline phosphatase의 분비 비율과 활성도를 측정하였다. 총 세균은 $3.2{\times}10^{5}$ - $3.2{\times}10^{6}$ cells/${\mu}\ell$의 범위였으며, 종속 영양세균의 총 세균수는 0.07-2.63%이였다. 종속영양세균의 종 당양성은 여롬과 양어장 인근, Peridinium이 발생하는 곳에서 낮았다. Pseudomonas. Flavobacterium은 모든 정점에서 우점종으로 나타났다. Alkaline phosphatase를 분비하는 비율과 활성도는 Flavobacterium에서 높게 나타나, 유기인산염 분해에 우점세균 중 가장 큰 기여를 하는 것으로 밝혀졌다.

• 한국미생물·생명공학회지
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• 제46권2호
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• pp.127-134
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• 2018

본 연구에서는 해조류인 Umbraulva japonica의 표면에서 79개의 세균을 분리하였다. 16s rRNA 유전자 분석 결과, 주요 계통군은 Proteobacteria (74.69%), Actinobacteria (2.53%), Fimicute (2.53%), Bacteroidetes (20.25%)로 4개의 문(Phylum)이 관찰되었고, 7개의 강(Class), 13개의 목(Order), 17개의 과(Family), 31개의 속(Genus)을 확인하였다. 계통학적 분석 결과 3개의 균주가 표준균주와 97% 이하의 유사성을 보여 신속 또는 신종으로 보고될 가능성이 있다고 여겨지며, 향후 표준균주들과 함께 추가적인 신종 실험이 수행되어야 할 것으로 사료된다. 분리된 79 균주를 이용하여 인체 및 어류 병원균을 대상으로 항균 활성을 확인하였다. UJT7, UJT20, UJR17의 균체 현탁액이 Vibrio vulnificus에 대하여 항균 활성을 나타냈으며 UJR17의 균체 현탁액은 V. vulnificus와 Streptococcus parauberis에 항균 활성능이 있음을 확인하였다. UJT7은 Bacillus sp., UJT20과 UJR17은 Pseudomonas sp.로 확인되었으며 다양한 활용을 위한 추가적인 실험을 수행한 후 유익하게 이용 될 수 있을 것이라 사료된다.

• 대한소아치과학회지
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• 제34권1호
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• pp.19-26
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• 2007

본 연구의 목적은 정신지체 학생의 구강건강 실태 및 치아우식 활성도를 평가하여, 학생들의 구강건강 증진을 위해 필요한 교육 방안을 모색하고, 실제적인 구강건강 관리 향상을 위한 기초 자료를 마련하고자 하는 것이었다. 광주광역시 소재 S 정신지체특수학교 유아부부터 고등부까지의 학생을 대상으로 조사를 실시하였다. 구강건강실태를 평가하기 위한 구강검사는 213명에 대해 시행하였으며, 치아우식활성도 검사는 197명에 대해 시행하였다. 치아우식활성도 평가를 시행한 197명의 정신지체 학생 중 우식활성이 고도인 학생은 33명(16.77%)으로 나타났으며, 13세 이하가 그 이상의 연령에 비해 치아우식활성도가 높았다. 치아우식활성도의 경중도와 치은염 유무와는 관련성이 없는 것으로 나타났다. 정신지체 장애학생의 치아우식활성도 경중과 치아우식경험지수와의 상관성을 평가한 결과, 치아우식활성도가 증가할수록 우식경험치율과 우식경험치지수가 높은 양상을 보였으며, 특히 유치의 경우 우식경험유치율 및 우식경험유치지수는 치아우식활성도와 높은 상관성을 보였다.

• 한국식품저장유통학회지
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• 제9권1호
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• pp.102-108
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• 2002

동충하초(눈꽃 동충하초, 번데기 동충하초), 쑥 및 솔잎 추출물의 항균작용을 조사하기 위하여 동충하초의 자실체와 균사체, 쑥 및 솔잎을 물과 70% 에탄올로 추출하였다. 항균실험에는 3종류의 그람양성균(Bacillus subtilis, Listeria monocytogenes, Staphylococcus aureus)과 3종류의 그람음성(Escherichia coli, Shigella sonnei, Salmonella typhimurium) 식중독 및 병원성 세균을 사용하였다. 동충하초의 추출수율은 물과 에탄올 모두 자실체의 수율(39∼58%)이 균사체(9∼24%)에 비하여 2.4∼4.4배 높았으며, 쑥과 솔잎 추출물의 수율은 9%미만이었다. 눈꽃 동충하초의 에탄올추출물(JME)은 1%농도에서 L. monowtogenes에 대하여 항균활성을 나타내었으며 번데기 동충하초의 에탄올추출물(MFE)은 3%농도에서 S. aureus에 대하여 항균활성을 나타내었다. 쑥의 에탄올추출물(MGE)은 1% 농도에서 L. monocygenes와 S. aureus에 대하여 항균활성을 나타내었으나 눈꽃 동충하초, 번데기 동충하초 및 쑥의 물추출물은 시험균주에 대하여 항균활성을 나타내지 않았다. 솔잎 물추출물은 E. coli를 제외한 모든 균주에 대하여, 솔잎 에탄올추출물은 실험에 사용한 모든 균주에 대하여 항균활성을 나타내어 솔잎추출물들은 가장 폭넓은 항균스펙트럼을 나타내었다. 액체배지내에서 솔잎추출물의 세균증식 억제작용은 에탄올추출물이 물추출물에 비하여 큰 편이었다.

• Journal of Microbiology
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• 제35권4호
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• pp.284-289
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• 1997

A Gram (-), rod-shaped bacterium $2.3{\sim}2.8{\times}0.45{\mu}m$ in size which exhibited growth-inhibiting effects against a cyanobacterium (Anabaena cylindrica) was isolated from Daechung Dam Reservoir. This isolate was identified as Moraxella sp. and designated Moracella sp. CK-1. Hollow zones formed around bacterial colonies on the cyanobacterial lawn. In a mixed-culture of A. cylindrica and the isolate, each microorganism grew inverse-proportionally, and the cyanobacterial vegetative cells completely disappeared within 24 hours. On treatment with Moraxella sp. CK-1, cell walls of A. cylindrica disappeared, but sheathes remained in a more electron dense form. The unit membrane such as thylakoidal membrane was stable to bacterial lysing activity. This bacterium showed a broad action spectrum against cyanobacteria. The growth-inhibiting activity of Moracella sp. CK-1 against A. cylindrica is believed to be performed through the excretion of active substances.

• Asian-Australasian Journal of Animal Sciences
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• 제4권3호
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• pp.281-284
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• 1991

Combination effects of sulfamethoxazole (SMX) and trimethoprim (TMP) against nine gram positive bacterial strains and 43 gram negative bacterial strains which included 40 strains of animal intestinal bacteria were studied in vitro. Minimum inhibitory concentrations (MICs) of SMX and TMP alone and 20:1 (SMX : TMP) mixture (ST) were investigated by the method recommended by Ad Hoc Committee of the Japan Society of Chemotherapy for the Evaluation of Sensitivity Testing Methods for Sulfamethoxazole and Trimethoprim. MICs of ST were more potentiated than those of SMX alone in 8 of 9 gram positive strains and 40 of 43 gram negative strains. Especially, 38 strains of 40 intestinal bacteria showed significant susceptibility to ST as compared to SMX. These results suggest a strong synergistic activity of ST mixture against animal intestinal bacteria, The activity was considered to be comparable to those of other current antibiotics.

• 한국식품영양과학회지
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• 제23권5호
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• pp.849-855
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• 1994

Actively growin Excherichia coli(KCTC 1039) cells were treated with paraquat (1, 1'-dimethyl-4, 4'-bipyridili-um dichloride) by cultivating them in the presence of 1.0mM paraquat. The treatment was carried out with or without shaking to understand the effect of oxygen on paraquat action to thebacterial superoxide dismutase (SOd). By the treatment with vigorous shaking , population growth of the organism almostly stopped and specific activities of SOD of the cells drastically decreased. On contrast ot it, the herbicide showed only l limited inhibitory action on bacterial growth and SOD activity by stationary treatment. Proteins prepared from parquat-treated cells divided into two peaks by Sephacryl column chormatogrpahy, while proteins from the intact cells formed a single peak. Cytoplasmic proteins and plasma membrane proteins of intact cells formed separated three peaks by Sephadex G-75 column chormatography. respectively. Among them the second peak disappeared by paraquat treatment , while the third peak became more apparent. Fractions from the first and the third peak showed SOD activity. Paraquat was detected from the same fractions.

• Ocean and Polar Research
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• 제24권1호
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• pp.47-53
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• 2002

To evaluate the effect of reed population on the distribution and activities of microorganisms, vertical distribution of heterotrophic bacteria, degradation rate of cellulose, extracellular aminopeptidase activity (APA) and metabolic diversity based on GN2 Microlog plate were measured at two salt marsh stations in Hogok-ri, Namyang Bay, west coast of Korea. The number of heterotrophic bacteria at station 1 (reed population inhabited area) showed 2 to 6 times higher than that of station 2 (exposed area) with exception in the surface layer. Cellulose degradation rates in station 1 showed more than 50%. month-I and higher than that of station 2 (10.2 to 38.4%. $month^{-1}$). Yet the APA at two stations did not show difference except surface layer and suggested that APA might not be a significant factor in degrading marsh plant debris. Lipid class compounds, cell wall polymers and L-alanine were widely used by microorganisms. The number and activities of bacterial populations especially concerned in plant debris degradation seemed to be stimulated by the reed communities.

• 약학회지
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• 제46권1호
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• pp.24-29
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• 2002

Enoyl-Acyl Carrier Protein Reductase (Fabl) of bacteria is hem as an important target for new antibacterial drugs and plays a determinant role in completing cycles of elongation in type-H fatty acid synthase system. In this study, a fabI gene from Staphylococcus aureus 6538p cloned in pET-l4b vector and FabI protein was over-produced in Escherichaia coli BL2l (DE3). $NH_2$-terminal His-tagged FabI protein was purified by nickel-nitrilotriacetic acid (Ni-NTA) metalaffinity chromatography Purified 6xHis-tagged FabI showed a catalytic activity on tram - 2 - octenoyl - N -acethlcysteamine by utilizing NADPH as a cofactor. For the discovery of new FabI inhibitors from chemical libraries, a target-oriented screening system using a 96-well plate was developed. About 10,000 chemical libraries from Korea Chemical Bank wore tested in this screening system, and 26 chemicals (0.25%) among them showed an inhibitory activity against FabI enzyme. This result showed that a new screening system can be used for the discovery of new FabI inhibitors.