• Title/Summary/Keyword: 최소 억제 농도

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Biosynthetic Regulation and Enzymatic Properties of $\beta$-Glucosidase from Cellulomonas sp. CS 1-1 (Cellulomonas sp. CS1-1으로 부터의 $\beta$-Glucosidase의 합성조절과 그의 효소학적 성질)

  • Lee, Hee-Soon;Min, Kyung-Hee;Bae, Moo
    • Microbiology and Biotechnology Letters
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    • v.16 no.2
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    • pp.119-125
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    • 1988
  • $\beta$-Glucosidase of Cellulomonas sp. CS1-1 in cellular compartment was localized with cell-bound form while Avicelase and carboxymethylcellulase (CMCase) were appeared with extracellular enzyme. Cell growth on cellulose or CMC minimal broth was increased by glucose addition. $\beta$-Glucosidase production on cellobiose or CMC minimal broth was repressed by the addition of glucose. However, on CMC minimal broth, the enzyme production was specially stimulated by cellobiose addition. $\beta$-Glucosidase production was also induced by CMC, starcth and maltose compared with glycerol, arabinose, xylose and trehalose. From the above results, it was concluded that glucose effect on $\beta$-glucosidase biosynthesis showed catabolite repression, but enzyme production was induced by cellobiose, CMC, and starch, indicating that $\beta$-glucosidase is inducible enzyme. Yeast extract stimulated $\beta$-glucosidase production more than peptone and ammonium sulfate. $\beta$-Glucosidase activity was increased with 50mM MgCl$_2$in 10mM potassium phosphate buffer (pH 7.0). Optimum conditions for enzyme activities were pH 6.0 and 42$^{\circ}C$, Km value of $\beta$-glucosidase for p-nitrophenyl-$\beta$-D-glucosidase was 0.256mM and Ki for $\beta$-D(+)-glucose was 9.0mM.

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Resistance of Some Metal Ions on Growth of Serratia marcescens Strain P (Serratia marcescens Strain P 성장에 미치는 중금속 내성)

  • 유관희;이호용
    • Microbiology and Biotechnology Letters
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    • v.20 no.6
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    • pp.693-698
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    • 1992
  • The resistant effect of several heavy metal ions to Serratia marcescens strain P was studied by the method of minimal inhibitory concentration(MIC), and testing for their metal biosorption. S. marcescens strain P showed a good survival in the presence of high concentrations of some metal ions, namely cadmium, lead, iron, magnesium, and manganese. Copper had the most inhibitory effect among tested. The MIC value was ranged from 0.79 to 1.58 mM. Cells of S. marcescens strain P exhibit an abnormally long lag phase when incubated in high concentrations of zinc and cadmium. Pigment production was reduced by zinc and cadmium, but enhanced by lead and iron. S. marcescens strain P was resistant to ampicillin, tetracycline, cefamandole and chloramphenicol with minimal inhibitory concentration of 128 $\mu$g/ml, 32 $\mu$g/ml, 256 $\mu$g/ml, and 8 $\mu$g/ml, respectively. The kinetics study of biosorptive uptake by S. marcescens strain P revealed that 16.59% of cadmium and 35.38% of lead were eliminated from the media.

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Antimicrobial Activities of Sophorolipids and Its Application for Cosmetics (Sophorolipid의 항균효과와 화장품에의 응용)

  • Cho, Wan-Goo;Park, Hyo-Soon;Ahn, Byoung-Joon
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.34 no.4
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    • pp.317-323
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    • 2008
  • Some surfactants known as biosurfactants, are produced biologically by yeast and bacteria from various substances. They are more effective and environmentally friendly than many other synthetic surfactants. Antimicrobial activities of sophorolipids produced by Candida bombiocola were investigated against various microorganisms. Minimal Inhibitory concentration (MIC) of sophorolipid against S. mutans, C. xerosis, and P. acnes were 0.005, 0.05, and 0.005%, respectively. The antimicrobiological activities were more effective than those of SLS and APG. Skin exfoliating and moisturizing effects of vehicles with the sophorolipids were tested. The skin turnover time of aqueous solution with 0.25% sophorolipids was similar to that of aqueous solution with 5.0% lactic acid. Higher moisturizing effects on skin showed as the concentration of sophorolipids increased. We suggest that the sophorolipids can be used for cosmetics as an antimicrobiological agent and an active materials of skin moisturizing and exfoliating.

Antimicrobial Activity of Lentinus edodes Extract (표고버섯(Lentinus edodes)추출물의 항균활성)

  • 김용두;김경제;조덕봉
    • Food Science and Preservation
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    • v.10 no.1
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    • pp.89-93
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    • 2003
  • To develope natural food preservatives, ethanol and water extracts were prepared from the Lentinus edodes and antimicrobial activities were examined against 10 microorganisms which were food borne pathogens and / or food poisoning microorganisms and food-related bacteria and yeasts. Ethanol extract exhibited antimicrobial activities for the microorganisms tested, but not on lactic acid bacteria and yeast Especially, minimum inhibitory concentration(MIC) for Escherichia coli were as low as 0.5 mg/mL. Antimicrobial activity of the ethanol extract was stable by the heating at 121$^{\circ}C$ for 15 min and not affected by pH. The ethanol extract of Lentinus edodes exhibiting high antimicrobial activity. The highest antimicrobial activity adjust bacteria tested was found in the ethylacetate fraction.

Antimicrobial Activity of Methanol Extract from Rheum tanguticum against Food Hazardous Microorganisms and the Composition of the Extract (식품위해성 미생물에 대한 대황(Rheum tanguticum) 메탄올 추출물의 항균활성 및 성분분석)

  • 임미경;김미라
    • Korean journal of food and cookery science
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    • v.19 no.4
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    • pp.470-476
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    • 2003
  • Daehwang (Rheum tanguticum) was extracted by methanol, and the antimicrobial activities of the extract, against some food hazardous microorganisms, were investigated by the paper disc method. The minimum inhibitory concentration (MIC) of the extract against the microorganisms was determined, and the extract components were analyzed by GC/MS. The Daehwang extract showed the strongest antimicrobial effect against P. aeruginosa. The MICs on S. aureus, P. aeruginosa and S. typhimurium were 250, 300 and 300mg/$m\ell$, respectively. In the methanol extracts from Daehwang, 120 different compounds were separated, with the extraction yield of the phenolic compounds being relatively high (29.85%). Substances with antimicrobial activity, such as 2-methoxy-phenol and 4-vinyl-2-methoxy-phenol were detected in the study.

The Influence of Epinephrine Concentration in Local Anesthetics on Pulpal and Gingival Blood Flows (국소마취제에 함유된 에피네프린의 농도가 치수 및 치은 혈류에 미치는 영향)

  • Lee, Jae-Sang;Kim, Sung-Kyo
    • Restorative Dentistry and Endodontics
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    • v.28 no.6
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    • pp.475-484
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    • 2003
  • 동통조절을 위해 국소마취제는 치과임상에서 광범위하게 사용되어진다. 가장 널리 쓰이는 국소마취제는 리도카인이고 이는 마취효과의 지속 및 지혈효과 등의 목적으로 혈관수축제를 포함하고 있다. 대표적 혈관수축제인 에피네프린은 임상에서 1:300,000에서부터 1:50,000의 농도로 다양하게 사용되어진다. 수복치료를 위해서는 통상적으로 1:100.000농도의 에피네프린이 사용되고 있고 외과적 근관치료시 지혈효과를 위해서는 1:50,000농도의 에피네프린이 추천되고 있다. 이들 농도의 에피네프린을 포함한 리도카인으로 국소마취시 에피네프린의 농도가 치수의 혈류 및 치은의 혈류에 미치는 영향을 이해할 필요가 있고 그 영향이 전기치수검사에 대한 치수의 반응성에 미치는 영향도 이해할 필요가 있다. 따라서 혈관수축제를 포함한 국소마취제에 의한 치수혈류의 변화와 치수신경의 반응성을 이해하는 것은 중요하다 하겠다. 본 연구의 목적은 두 가지 농도의 에피네프린을 포함한 국소마취제로 마취시 나타나는 치수 및 치은의 혈류 변화를 치수신경의 반응성과 비교, 관찰함으로써 국소마취제가 치수 및 치은에 미치는 영향을 파악하고자 함에 있다. 24세에서 27세까지의 10명의 피검자의 건전한 상악중절치를 시험에 이용하였다. Laser Doppler flowmeter의 probe을 고정하기 위한 splint를 간접법으로 인상용 putty를 이용하여 제작하고 치수 및 치은의 혈류량, 그리고 전기치수검사에 대한 반응성을 측정하기 위한 3개의 구멍을 만들었다. 피검자를 10분간 안정시킨 후 마취 전 10분간 정상 혈류량과 전기검사치를 측정하고 1:50,000 epinephrine과 1:100,00 epinephrine이 각각 함유된 2% 리도카인 용액 0.9 ml를 상악 좌측 중절치 치근단부위 협점막에 침윤마취하였다. 마취 후 70분간 치수 및 치은 혈류량을 laser Doppler flowmeter를 이용해 연속적으로 측정하여 그 수치를 컴퓨터에 저장하였고, 매 5분 간격으로 전기치수검사를 시행하여 그 측정치를 기록하였다. 매 시간 간격의 평균 혈류량을 정상 혈류량에 대한 백분율로 나타내고, 각각의 농도에서 최소 치수 및 치은 혈류량을 Paired t-test, Wilcoxon's signed rank test. Duncan's multiple range test. Fisher's exact test등을 이용. 통계분석 하여 다음과 같은 결과를 얻었다. 에피네프린이 함유되어 있지 않은 리도카인을 협점막에 주사시 혈류변화가 거의 나타나지 않았으나 1:50,000 및 1:100.000 에피네프린이 함유된 2% 리도카인을 협점막에 침윤마취시 치수 및 치은 혈류 공히 현저히 감소하였다(p<0.01). 1:50,000 에피네프린군은 1:100,000 에피네프린군에 비해 치수 혈류량이 현저히 억제되어 나타났으나(p<0.01), 치은 혈류량에서는 유의성 있는 차이를 나타내지 않았다(p>0.05). 두 농도의 에피네프린 군 공히 치은혈류는 치수혈류에 비해 유의하게 많은 감소를 나타내었다(p<0.05). 1:100,000 에피네프린 군에서 마취액 주입 후 치수혈류 최대감소가 가장 먼저 나타났고 이어서 전기검사에 대한 치수의 반응성 소실 및 치은혈류 최대 감소의 순으로 나타났다(p<0.05). 1:50,000 에피네프린군의 경우가 1:100,000 에피네프린군의 경우에 비해 마취지속시간이 길게 나타났으나 유의성은 없었다(p>0.05).

In vitro and In vivo Antimicrobial Activities of Medicinal Plants against Crown Gall in Grapevine (포도나무 줄기혹병균에 대한 약용식물의 항균활성 및 병발생억제)

  • Kim, Eun Su;Yun, Hae Keun
    • Horticultural Science & Technology
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    • v.34 no.4
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    • pp.537-548
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    • 2016
  • The objective of this study was to evaluate the antimicrobial activities of 9 kinds of medicinal plants against crown gall in grapevine. The medicinal plants extracted with several solvent systems were screened for in vitro antibacterial activity by the disc diffusion method. The ethanol and ethyl acetate extracts from magic lily flowers, tachys roots, asian plantain flowers and seeds, sweet wormwood leaves, stems and flowers, immature bitter melon fruits, cockscomb flowers, and peach tree resin showed in vitro antimicrobial activities against Rhizobium vitis with growth inhibition zones ranging from 10 to 27 mm in diameter. The minimum inhibitory concentration values of extracts against R.vitis ranged from 10,000 in Asian plantain flower and 50,000 fold diluted extracts in sweet wormwood flowers, stems, leaves, cockscomb leaves and immature bitter melon fruits. The active fractions of ethyl acetate and ethanol extracts from the medicinal plants were partially separated through silica gel column chromatography and thin layer chromatography (TLC). The active fractions were separated at Rf 0.36, 0.69, 0.75, 0.84, and 0.94 in sweet wormwood extracts, Rf 0.96 and 0.99 in cockscomb flower extracts, Rf 0.92 and 0.97 in cockscomb leaf extracts, and Rf 0.85 in immature bitter melon fruit extracts in TLC analysis developed with hexane:ethyl acetate (20:80, v/v) and methanol:chloroform (20:80, v/v). Among extracts from plants with in vitro antimicrobial activities, sweet wormwood, cockscomb leaves, and immature bitter melon fruits showed in vivo antimicrobial activities with inhibition activity of 100, 67, and 83.3%, respectively, in 'Kyoho' grapevine inoculated with R. vitis compared with the untreated control. These findings indicate that extracts of medicinal plants could be used as sustainable candidates to control crown gall disease caused by R. vitis in grapevines.

Antimicrobial Activities of Sword Bean (Canavalia gladiata) Extracts against Food Poisoning Bacteria (식중독원인균에 대한 작두콩 추출물의 항균활성)

  • Chung, Jaekeun;Lee, Jeongchi;Ha, Dongrong
    • Journal of Food Hygiene and Safety
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    • v.29 no.4
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    • pp.376-382
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    • 2014
  • Various solvents (chloroform, hexane, ethyl acetate, ethanol, methanol, and hot water) were tested to investigate the antimicrobial activities of sword bean (Canavalia gladiata) against 12 food poisoning bacteria. Chloroform, hexane, ethyl acetate and hot water extracts had no antimicrobial activities, but ethanol extract showed V. parahemolyticus 10 mm, S. sonnei 9 mm, and methanol extract showed strong activities in order of V. parahemolyticus 22 mm, S. sonnei 21 mm, L. monocytogenes 20 mm by disk diffusion. The minimal inhibitory concentrations (MICs) were also determined. The methanol extract had MIC values of 50 mg/mL against S. Typhimurium, V. parahemolyticus, and S. sonnei and values of 100 mg/mL against other 7 food poisoning bacteria and values of 200 mg/mL against Y. enterocolitica and MRSA. The inhibitory effect of methanol sword bean extract on the growth of V. parahemolyticus was investigated. Growth of the strain occurred at the concentration of 0.5% extract and was inhibited continuously at 1.0 and 1.5% for 30hours after inoculation, whereas the strain was completely inhibited at 2.0% after 9hours of inoculation.

Studies on the Cumulus Expansion and Oocyte Maturation of Mouse Cumulus-Oocyte Complexes: Regulation of Intracellular cAMP Level (생쥐 난자-난구 복합체의 성숙과 분산에 관한 연구 : 세포내 cAMP의 조절)

  • 권혁방;고선근;임욱빈
    • The Korean Journal of Zoology
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    • v.30 no.1
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    • pp.1-9
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    • 1987
  • Cyclic AMP (cAMP) was known to play a key role in the regulation of cumulus expansion and oocyte maturation of mammalian cumulus-oocyte complexes (COC's) in vivo and in vitro. The present experiments were conducted to know how intracellular level of cAMP in these cells is controlled. Intracellular cAMP level was modulated by culturing mouse CGC's with an adenylate cyclase stimulator, forskolin, a phosphodiesterase inhibitor, 3-isobutyl-1-methyixanthine (IBMX), human chorionic gonadotrophin (HCG), or follicle stimulating hormone (FSH). The rate of cumulus expansion and germinal vesicle break-down (GVBD) was checked after culture and used as a biological end point. Forskolin in the medium began to stimulate the expansion of the complexes at 1 nM and induced maximum expansion (80~90%) at 0 1~10 $\mu$M. The expansion rate was reduced to 60% when forskolin concentration was increased to 100 $\mu$M. Oocyte GVBD occurred normally (75~82%) in the presence of 10 $\mu$M of forskolin, but partial suppression was appeared at 100 pM of the drug (40%). IBMX also stimulated the expansion from the concentration of 0.01 pM and induced full expansion (81~89%) between the concentration of 1-1000 $\mu$M. Meiotic resumption was occurred normally under 10 $\mu$M of IBMX, but suppressed drastically from the concentration of 100 $\mu$M. The minimum exposing time to hormone or drugs required to trigger cumulus expansion was two minutes with HCG, 15~30 minutes with FSH and fors kolin, and two hours with IBMX. The data presented here seemed to imply that intracellular cAMP level in cumulus cells is regulated by both adenylate cyclase and phosphodiesterase and cumulus expansion is induced by a peak of cAMP while meiotic arrest is maintained by continuous presence of cAMP.

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Service Life Assessment and Restrain Methods of Carbonation Attack on PC Outer Wall of LNG Storage Tanks (탄산염해에 대한 LNG 저장탱크 PC 외부벽체의 수명평가 및 억제방안)

  • Lee, Seung-Rim;Song, Il-Hyun;Kim, Han Sang
    • Journal of the Korean Institute of Gas
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    • v.18 no.2
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    • pp.73-80
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    • 2014
  • The objective of this paper is to assess the service life and retrain methods of specimens, which were subjected to carbonation attack, obtained from mix proportion of Sam-cheok LNG storage tank under construction. As the results, accelerated-carbonation penetration depths of 7, 28, 56 ages indicated 4.45, 9.19, 13.37mm, and even considering for cover depths of steel of LNG storage tank under real operation, it was enough. In addition, with carbonation velocity coefficient calculated by carbonation penetration depths, the service life to design cover depth(70, 80, 90, 100mm) of PC outer tank of LNG storage tank was 779, 1017, 1287, 1589 years and 466, 609, 771, 951 years, respectively, considering the $CO_2$ concentration in air which account for the 0.03% and 0.05%. Also, the restrain methods to carbonation attack were feasible through controlling the factors affecting the changes of hydration products such as $Ca(OH)_2$, ion composition in pore solution and matter mobility of organization structures within hardened concrete.