• 한국균학회지
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• 제16권1호
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• pp.33-40
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• 1988

시판 감귤의 과피에서 naringin을 분리하고 가수분해하여 얻은 naringenin의 항균시험을 실시한 바 세균에서 naringin은 gram 양성균보다 gram 음성균이 비교적 강한 항균력을 나타내었으나 naringenin은 그 반대 현상을 나타내었다. 또 naringin과 naringenin의 항균력을 비교하면 전체적으로 naringenin이 매우 강한 항균작용이 있다. 안전성 시험에서 $LD_{50}$은 1650 mg/ kg이고 헐액임상화학적 검사에서 대조군과 비교하여 아무런 이상을 발견할 수 없었으며 병리조직학적 검사에서의 현미경 관찰에서도 대조군과 같았으며 투여군에 대해 조직학적 병변이 나타나지 않았으므로 안전성이 없다고 사료된다.

• 생약학회지
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• 제31권1호
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• pp.72-76
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• 2000

This study was carried out to evaluate cytotoxic effects of Ajuga multiflora Bunge extracts on murine leukemia tumor $(P388D_1)$ cell lines. Disruptions in cell organelles were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazoliumbromide (MTT) assay. The comparison of $IC_{50}$ values of Ajuga multiflora Bunge extracts in L1210 and $P388D_1$ cell lines showed that their susceptibility to these extracts decreased in the following order: Adriamycin>methanol extract>chloroform extract>ethyl acetate extract>hexane extract>water extract by the MTT assay. In order to develop an antimicrobial agent, dried Ajuga multiflora Bunge was extracted with several solvents, and then antimicrobial activity was investigated. The minimal inhibitory concentration (MIC) of the extract against microorganisms were also examined. Antimicrobial activities of amocla and ketoconazole as references were compared to those of extracts of $H_2O$, n-hexane, chloroform, ethyl acetate and methanol. The antimicrobial activity of all extracts from the sample had growth inhibition activity against gram-negative bacteria, gram-positive bacteria and fungi $(MIC>200\;{\mu}g/ml)$. These results suggest that the methanol soluble extract of Ajuga multiflora Bunge may be a valuable choice for the studies on the treatment of murine leukemia tumor cell lines.

• 한국미생물·생명공학회지
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• 제40권4호
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• pp.380-388
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• 2012

북극 지의류로부터 서로 다른 5종의 극지 미생물을 분리하였고, 그들의 생리활성 물질들은 아세톤, 물, 클로로포름, 다이에틸에테르, 에탄올, 에틸아세테이트, 메탄올 및 페트롤륨 에테르 등 다양한 용매를 이용하여 균 배양액으로부터 추출되었다. 이러한 추출물들의 항균성은 Staphylcoccus aureus, Bacillus subtilis, Micrococcus luteus, Enterobacter cloacae, Pseudomonas aeruginosa 및 Escherichia coli 등 6종의 병원체에 대한 디스크 확산법과 최소억제농도 측정법에 의해 조사되었다. 여러 추출 샘플 중, Burkholderia sordidicola S5-$B^T$ (KOPRI 26644) 유사미생물 종의 에틸아세테이트 추출물이 표적박테리아에 대한 높은 항균활성을 나타내었다(억제대, 7-10 mm; 최소억제농도, $57.5{\rightarrow}1000{\mu}g/ml$). 또한, 다양한 추출 용매 중, 클로로포름 추출물에서 약하지만 분명한 활성을 나타내었다.

• 대한의생명과학회지
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• 제5권1호
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• pp.27-40
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• 1999

본 연구는 MarA와 함께 MarB가 AcrAB efflux pump를 목표로 하는지 여부, 그리고 항생제의 균체외 배출기능에 대하여 어떤 조절 작용이 있는지를 항생제 내성검사를 통하여 살펴보았다. 본 연구 결과는 MarB가 MarA와 함께 AcrAB/TolC efflux pump의 항생제 배출기 능을 억제적으로 조절한다는 것을 간접적으로 보여 주었으며, 한편 이미 알려진 대로 MarA는 acrRAB operon의 발현을 전사 수준에 서 positive regulation하므로, MarB는 AcrAB efflux pump의 기능을 억제적으로 조절한다는 것을 암시하고 있다. 그리고 MarA와 함께 MarB단백질의 작용 목표는 AcrAB efflux pump임을 간접적으로 보여주고 있다. 또한 MarB는 MarA와 함께 대장균의 다른 efflux system(들)의 항생제 배출기능에 대해서도 억제적으로 조절할 가능성이 높은 것으로 나타났다.

• 약학회지
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• 제43권4호
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• pp.419-422
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• 1999

In order to develop a antimicrobial agent, dried Sophora flavescens Ait. was extracted with several solvents, and than antimicrobial activity was investigated. The minimal inhibitory concentration (MIC) of the extracted substance against microorganisms were also examined. Antimicrobial activity of the initial methanol extract from the sample was the strongest compared to those of other solvent extracts such as $H_2O$, n-hexane, chloroform, ethyl acetate and methanol. The methanol extract had strong growth inhibition activity against gram-postive bacteria (MIC, $25~50{\;}{\mu\textrm{g}}/ml$) such as B. subtilis. Among gram-positive bacteria tested, B. subtilis was the most susceptible to the extracted substance. The antimicrobial activity of the methanol extract from the sample had strong growth inhibition activity against gram-negative bacteria such as P. aeruginosa (MIC, $25{\;}{\mu\textrm{g}}$/ml).

• Journal of Periodontal and Implant Science
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• 제35권2호
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• pp.401-411
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• 2005

The aim of this study was to determine the minimal inhibitory concentration(MIC) of cefixime, which is a 3rd generation of cefalosporin, against 6 species of putative periodontopathogens; Fusobacterium nucleatum, Actinobacillus actinomycetemcomitans, Prevotella intermedia, Prevotella nigrescens, Tannerella forsythia and Porphyromonas gingivalis. The efficacy of cefixime was examined by comparing it with that of several antibiotics(amoxicillin, $Augmentin^{(R)}$ ciprofloxacin, metronidazole, and tetracycline), which were used as the control. The MIC was measured using a microdilution method. The MIC of cefixime against the putative periodotopathogens, as a single use regimen, was relatively lower than that of the other antibiotics. The MIC of cefixime/metronidazole against P. intermedia ChDC KB14, P. nigrescens ChDC KB50, F. nucleatum ChDC PV-F37, F. nucleatum ChDC F130, and F. nucleatum ChDC F175, as a simultaneous regimen, was lower than that of the other antibiotics. The concentration of cefixime in the crevicular fluid of volunteers who received 250mg every 12 hours for 3 days was $9{\mu}g/ml$ after 9 hours. In conclusion, cefixime showed good antimicrobial activity in a single treatment or as a combined therapy with amoxicillin, $Augmentin^{(R)}$ or metronidazole against 6 periodontopathogens.

• 한국균학회지
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• 제23권1호통권72호
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• pp.28-36
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• 1995

53종의 한국산 야생버섯 중 12종의 버섯으로부터 석유에테르, 80% 에탄올 및 증류수로 추출하여 얻은 14개의 추출물이 6종의 그람양성균에 대하여 각각 선택적으로 항균활성을 나타내었다. 3 종류의 추출용매 중 에탄올 추출물에 대부분의 항균활성이 존재하였으며, 특히 Thylopilus PS-5, Pulveroboletus PS-7 및 Russula PS-9의 추출물들은 다른 종의 버섯에 비교하여 항균활성의 선택성이 다양하였다. Pulveroboletus PS-7과 Boletus PS-8의 에탄올 추출물은 B. subtilis에 대하여 $300\;{\mu}g/ml$, Trichaptium PS-3의 에탄올 추출물은 M. luteus에 대하여 $500\;{\mu}g/ml$를 나타내었으며, 이외의 추출물은 모두 $1000\;{\mu}g/ml$ 이상의 비교적 큰 값의 MIC를 나타냄으로써 향후 좀 더 정제단계를 거쳐 이상의 버섯 중의 항균활성 물질의 구명을 위한 연구를 시도할 필요가 요구된다.

• 대한소아치과학회지
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• 제36권1호
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• pp.1-11
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• 2009

Essential oil은 식물로부터 추출한 휘발성의 호지방성 화합물로서 essential oil은 잠재적으로 항균, 항진균, 진경련, 항말라리아성, 곤충퇴치능력 등의 생물학적 효과를 가지고 있다. 본 연구에서는 다양한 방향식물에서 추출한 Citral, Pineole, Linalool, Eugenol, Limonene, Pinene 등으로 구성된 다섯종류의 essential oil을 사용하였으며, 여덟 군의 중요한 병원성 세균인 Streptococcus mutans(S. mutans), Staphylococcus aureus(S. aureus), Streptococcus sanguis(S. sanguis), Streptococcus anginosus(S. anginosus), Actinobacillus actinomycetemcomitans(A. actinomycetem- comitans), Streptococcus sobrinus(S. sobrinus), Staphylococcus epidermidis(S. epidermidis), Esherichia coli (E. coli)에 대한 저항성으로서 항균능력을 평가하였다. Essential oil의 항균능력은 용액희석방법을 사용하여 검사하였으며, essential oil 농도범위는 10 mg/mL, 5 mg/mL, 2.5 mg/mL, 1.25 mg/mL, 0.625 mg/mL, 0.516 mg/mL, 0.3125 mg/mL, 0.078 mg/mL, 0.039 mg/mL, 그리고 0.015 mg/mL였다. Essential oil은 용량 의존적으로 시험 균주의 성장을 효과적으로 억제하였으며, NM을 제외하고 R, LG, FR, O oil은 저농도에서 구강 병원성 미생물의 성장을 억제하였다. 또한 사용된 essential oil은 E.coli와 S. epidermidis의 성장에는 탁월한 억제효과를 보이지는 못했으나 구강 병원성 미생물에 대해서는 특별한 성장 억제효과를 나타냈다.

• 미생물학회지
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• 제38권4호
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• pp.265-265
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• 2002

Iron increased the susceptibilities of clinical isolates Pseudomonas aeruginosa to quinolones. In the presence of iron, increased susceptibilities to ofloxacin were observed in twenty-six out of thirty isolates and with no change in four isolates. In the case of norfloxacin, iran increased susceptibilities of twelve isolates but did not render any change in eighteen isolates. In the case of ciprofloxacin, iron decreased the MICs (Minimal Inhibitory Concentration) of twenty isolates, increased the MIC of one isolate, and did net change the MICs of nine isolates. To find out how iron increased susceptibility to ofloxacin, bacterial cells were grown in Muller Hinton (MH) media and succinate minimal media (SMM) to induce iran acquisition systems and the intracellular ofloxacin concentrations were assayed in the presence of iron. The addition of iron to the media decreased the MICs of cells whether they were grown in MH or SMM. Siderophores, carbonyl cyanide m-chlorophenylhydrazone (an inhibiter of proton motive force), and ouabain (an inhibitor of ATPase) did not decrease the effect of iron. Results suggested that the increase in the intracellular ofloxacin concentration by iron is accomplished not by decreasing the efflux but by increasing the of ofloxacin permeability.

• Archives of Pharmacal Research
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• 제19권2호
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• pp.143-147
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• 1996

LB20304 is a novel fluoroquinolone that exhibits a potent broad spectrum antibacterial activity against both gram-positve and gram-negative bacteria. The MICs (Minimal Inhibitory Concentration) of LB20304 were determined against both gram-positve and gram-negative bacteria under various conditions including several media, pHs, and inoculum concentrations. The in vitro activity of LB20304 was not significantly affected by the changes in testing conditions such as components of media and inoculum concentrations, but it was slightly reduced by acid condition. The MICs and MBCs (Minimal Bactericidal Concentration) of LB20304 against Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa were hardly affected by the presence of 50 % human serum, mouse serum, guinea pig serum or horse serum, and the MBCs were equal to or at most four-times higher than the MiCs. The activities of LB20304 were decreased by the presence of high concentraion of $Mg^{++}$ or human urine (pH, 5.5) in the test media. The frequencies of mutants resistant to LB20304 were similar to or lower than those found in ciprofloxacin and sparfloxacin.