• Korean Journal of Microbiology
• /
• v.40 no.2
• /
• pp.111-114
• /
• 2004

This study was carried out to evaluate the inhibition of growth and collagenase activity of Salvia miltiorrhiza Bunge against microorganisms causing periodontal diseases. The ethanol extract of Salvia miltiorrhiza showed sig-nificant growth inhibition against microorganisms causing periodontal diseases. Ethanol extract was further fractionated with organic solvents in the order of hexane, chloroform and ethyl acetate. Among the fractions tested, the hexane fraction showed the highest cell growth inhibition. The minimal inhibitory concentration (MIC) of the extract against C. curvus, C. rectus, E. corrodens, F nucleatum, P. gingivalis, P. intermedia and W. succinogenes were 200, 50, 50, 250, 150, 250 and 200 ${\mu}g$/ml, respectively. The inhibition of collagenase activity by organic solvent fractions were higher than that of minocycline, and the inhibition ratio of collagenase activity was $88.2{\pm}2.1$ % in the chloroform fraction.

• Proceedings of the KIEE Conference
• /
• 2002.07c
• /
• pp.1997-1999
• /
• 2002

고분자 주쇄(Main chain)의 소수성을 가지는 플루오르 그룹을 배제시킨 습도 민감성 폴리이미드를 합성 및 이미드화 하였고, 이를 이용한 초고참도 습도 센서를 제작 및 측정하였다. 사용된 폴리이미드는 다이아민계로 Oxydianyline(ODA)와 다이안하이드라이드계로 Pyromellitic dianhydried(PMDA)를 유기용매 Dimethyla cetamide(DMAc) 하에서 폴리이미드 전구체 (Polyamic acid)를 합성하였으며, 진공 및 승온 조건에서 유기용매를 제거하여 이미드화(Imidization) 반응을 진행시켜 제조하였다. 본 습도 센서는 정전용량형 고감도 습도 센서로 디자인되었으며 실리콘 웨이퍼상에서 일반적인 반도체 공정을 이용하여 구현하였다. 본 습도 센서는 센서 크기와 유효면적, 감습층의 두께를 주요 변수로 설정하였으며 이에 따른 습도 민감성 효과를 평가 및 분석하였다. 측정 결과 유효면적 70%, 감습층 두께 $1.1{\mu}m$ 로 제작된 습도 센서는 상대숨도$20%{\sim}90%$ 영역에서 캐패시턴스와 선형적 상관관계를 보여주고 있으며, 습도 민감도는 3.9 pF/%RH 클 얻을 수 있었다.

• Journal of Ginseng Research
• /
• v.13 no.1
• /
• pp.66-70
• /
• 1989

The specific growth rate was investigated to find the of(emits of major ginseng components in fractions extracted by several solvents on the growth of Candida parapsilosis. The cell proliferation of C. purapsilosis was inhibited by fraction A(hexane soluble components), while enhanced by fraction B(Et2O soluble components), C(AcOEt soluble components), E and F(dialysis outer and inner extract). The additive stimulant effect of cell proliferation was exerted by fraction D(crude saponinE) and B, C or E.

• Korean Journal of Food Science and Technology
• /
• v.29 no.6
• /
• pp.1327-1329
• /
• 1997

A new rapid saponin extraction method was developed with using of organic solvent and waring blonder. There was a good correlation between previous distillation method and this method in f major ginsenosides ($Rb_1$, $Rb_2$, Rc, Rd, Re, Rg1) contents. When the ratio of methanol and chloroform was 7:3, this method showed similar saponin contents (total major. ginsenosides contents) comparing with distillation method. Contents of total major ginsenosides were 2.41% in this method and 2.54% in distillation method. However, crude saponin content of this method was higher than that of distillation method.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2007.11a
• /
• pp.206-206
• /
• 2007

The nano-technology becomes a key technology in every field and it wasn't specialized any more. But nano-technology didn't applied every fields actively. Because It is difficult to fabricate the nanocomposites using nano-partie without aggregation of nano-size particles. So many researcher used organic solvent for dispersion in polymer nanocomposites. But organic solvent affected the electrical, mechanical, and thermal properties in the sample. We aimed this point that investigated the effect of organic solvent in the sample by evaporated temperature(60, 80, $100^{\circ}C$). In results, nano-particles affected to electrical properties of the sample due to decrease the energy gap. And at 120 Hz, impedance value of samples by varied evaporated temperature was decreased only at $60^{\circ}C$ dramatically. It's means that organic solvent role to impurities and decreased the activation energy. And these impurities contributed to the conductivity in the sample.

• Journal of Radiation Protection and Research
• /
• v.24 no.1
• /
• pp.1-7
• /
• 1999

Using the TBP slovent extraction method, a simple and precise method for determining uranium isotopes in the environment samples was developed. The soil sample was decomposed with $HNO_3$ and HF. Uranium isotopes were extracted with 15% TBP in $CCl_4$ from aqueous phase to organic phase, and Th fraction was removed with 8M HCl. Uranium fraction was purified in back extraction step with 1M HCl. Optimized electrode position conditions of uranium Isotopes were set using a new electrode position solution including a DTPA chelating agent. The new method of uranium isotopes determination was validated with a result of application to IAEA Reference Soils.

• Journal of Marine Bioscience and Biotechnology
• /
• v.1 no.4
• /
• pp.260-267
• /
• 2006

The Liquid Culture Assay using a recombinant Agrobacterium tumefaciens strain has been developed as a means for quorum sensing autoinducer screening. However, the low aqueous solubility of marine natural product extracts used as potential autoinducers has been a hindrance in the screening process. Although the addition of organic solvents and/or surfactants could increase aqueous solubility, errors in data interpretation including false positive results could be a serious problem. Therefore, determining the best possible solvent and surfactant at the optimum concentration is crucial. Evaluating methanol, ethanol, 1-propanol, DMSO and DMF at concentration ranges of 0~10% revealed < 2% methanol to be most favorable when tested for ${\beta}$-gal activity and growth inhibition of the recombinant A. tumefaciens strain. On the other hand, among surfactants tested, Triton X-100 was similarly effective in increasing the delivery of autoinducers for activity at less than 0.05% concentration.

• Polymer(Korea)
• /
• v.35 no.5
• /
• pp.458-466
• /
• 2011

In the mixed system of supercritical carbon dioxide/organic solvents, poly(vinyl alcohol)(PVA) film of high degree of hydrolysis could be dyed with a dichroic dye of C. I. direct black 22(DB22) and as a result, high durability was obtained. Especially, as a dye dispersant in a supercritical fluid phase, a mixed solvent system of ethylene glycol: dimethyl sulfoxide=4 : 6 weight ratio was investigated. Then the optimum pressure for dyeing could be reduced down to 200 bar. Using this supercritical fluid system, the maximum dyeing appeared as the transmittance of less than 1% and the waste amount was reduced to the level of 1/10. After 500% drawing of this PVA film, both the polarizing efficiency of 94% and the single piece transmittance of 30% were obtained. The limitation of DB22 and further improvements were also discussed.

• Korean Journal of Microbiology
• /
• v.33 no.3
• /
• pp.181-186
• /
• 1997

Sugar ester compounds were synthesized in organic solvent using lipase. Anhydrous pyridinc was selected as ;I solvent because of reasonable solubility of sugar. The synthesis of sugar ester compound was catalyzed by Pseudomonas sp. lipase in the reaction system containing anhydrous pyridine as .i solvent and vinyl butylate as an acyl donor. The analysis of the reaction product by TLC and GC showed thilt monobutyryl and dibutyryl fructose esters were synthesized by transesterification reaction between fructose and vinyl butyrate. Optimal conditions for the transesterification reaction were as follows: the ratio of fructoselvinyl butylate, I : lO(M : M): reaction temperature, 40^{\circ}C.$, velocity of shaking, 150 rprn: concentration of enzyme, 10 mglml. The longer the reaction period, the higher the conversion rate, and the conversion rate reached up to 90% after about 10 days of reaction. Monobutyryl fructose was mainly synthesized in the early stage of reaction, but the amount of dibutyryl fructose increased gradually as the rcdction progressed. When a small amount of water was added to the reaction mixture (micro-water system), the reaction rate decreased, while that of rnonobutyr~l fructosc increased. Only monobutyryl fructose was obtained when 1% water was added to the reaction mixture.

• Applied Biological Chemistry
• /
• v.50 no.2
• /
• pp.132-135
• /
• 2007

The effects of rose flower extracts on the growth of CHO cells were examined. Rose flower extracts were prepared by solvent extraction with hexane, ethylacetate and ether from five domestic rose cultivar, Rosa hybrida L. cv. Mihyang, Noeul, Redqueen, Whitelady and Pinklady, respectively. The effects of rose flower extracts on the growth of CHO cells were measured using MTT colormeteric assay and compared with control. Extracts of rose flowers showed stimulative effect or inhibitory effect on the growth of CHO cells depending on the kinds of solvent and concentration of extracts. Ether extracts of rose flower showed a more effective stimulative effect on the growth of CHO cells at the concentration of 5 ${\mu}g{\cdot}ml^{-1}$. These results suggest that rose flower has the simulating activity on the growth of CHO cells and a potential as new functional food source.