• Title/Summary/Keyword: solvent system

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Peroxidase를 이용한 cardol의 중합과 경화 거동

  • Park, Seung-Yeong;Kim, Yong-Hwan;Ryu, Jeong-Yong;Song, Bong-Geun
    • 한국생물공학회:학술대회논문집
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    • 2003.04a
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    • pp.121-125
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    • 2003
  • Enzymatic polymerization of cardol derived from cashew nut shell liquid have been examined. t-Butyl alcohol aqueous systems showed high yield of polycardol when SBP was as biocatalyst. Compared other solvents, peroxidase actiyity was maintained stable, which was seemed major cause. Solvent aqueous system and concentration of hydrogen peroxide were found to have an influence on the yield and molecular weight distribution of polycardol under the reaction of enzymatic polymerization using peroxidase. The polymer was subjected to the hardening by methyl ethyl ketone peroxide and cobalt naphthenate catalyst, giving a crosslinked tough film. Polycardol was cured rapidly and the hardness increased with time. Finally, the pencil scratch hardness reached to 7H, which is enough hard for industrial uses.

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pH-Sensitive Curdlan Acetate Microspheres를 이용한 Indomethacin의 방출 특성

  • Lee, Chang-Mun;Lee, Yeong-Jin;Lee, Gi-Yeong;Choe, Chun-Sun
    • 한국생물공학회:학술대회논문집
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    • 2003.04a
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    • pp.739-742
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    • 2003
  • Curdlan acetate was prepared from hydrophilic curdlan by chemical modification and it was used for pH-sensitive drug delivery system. Curdlan acetate microspheres were prepared by the solvent evaporation method. The size of the curdlan acetate microspheres was below $200\;{\mu}m$. The drug loading efficiency of microspheres was approximately 58.44%. In the swelling test, curdlan acetate microspheres were showed pH-sensitive behavior. The swelling capacity of microspheres at pH 7.4 was much greater than at pH 1.4. Also, Release rate of indomethacin (IND) at pH 7.4 from curdlan acetate microspheres was faster than that at pH 1.4. A pH-sensitive drug release pattern was due to the disintegrating after swelling.

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Quantitative Analysis of Cyanidin-3-Glucoside from Purple-Colored Crops (유색작물의 Cyanidin-3-Glucoside 최적 추출분석)

  • Kim, Eun-Shil;Shin, Jin-Chul;Chung, Ha-Sook
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.51 no.spc1
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    • pp.103-106
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    • 2006
  • Anthocyanins are water-soluble glycosides and acylglycosides of anthocyanidins, having different color variations due to its substitution patterns. Anthocyanins, present in various fruits, vegetables and crops as natural colorant, have been well characterized for its bioactive properties, anti-oxidant, anti-cancer, anti-proliferative and anti-inflammatory properties. During extraction and purification, the factors, such as pH, temperature, oxygen, light, enzymes, nucleophilic agents, sugar derivatives and co-pigments, have affected on anthocyanin stability. For this reason, the extraction method should be thoroughly checked for the qualitative/quantitative analysis of anthocyanin in particular plant material. To identify the optimum extraction method of cyanidin-3-glucoside, major anthocyanin of dark purple-colored grains, Oryza sativa cv. Heugjinjubyeo, Phaselous vulgaris, Phynchosia gngularis, Sesamum indium, Rhynchosia nulubilis and Lablab purpureus, reversed-phase HPLC analysis using solvent system of acetonitrile, methanol and water were accomplished.

An Experimental Study on the Spray Structure of a Gasoline Engine Injector (가솔린 기관용 인젝터의 분무 구조에 관한 실험적 연구)

  • Cho, B.O.;Lee, C.S.;Im, K.S.
    • Transactions of the Korean Society of Automotive Engineers
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    • v.3 no.1
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    • pp.118-130
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    • 1995
  • Fuel spray in a gasoline engine is a significant factor for the decision of engine power, pollutant emission and the design of intake manifold system. Three kinds of fuel which has other physical properties are chosen in this study, and it is observed using an image processing method that the mechanism and structure of free fuel spray with a throttle type gasoline injector, and the detailed characteristics of droplet size and velocity distributions are obtained by macro and micro-scopic measuring method respectively. It is verified that the initial breakup behaviors are depended on We like the result of Reitz's study, and also observed that the spray of octane and solvent with Re of 210~330 and 270~330 respectively are better than ethanol which has relatively high density and viscosity.

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Quantitative Analysis of Chemical Constituents in Psoraleae Semen and the Processed Psoraleae Semen (보골지와 염초보골지의 성분 정량 분석)

  • Kim, Yu-Jin;Shim, Sang-Hee
    • Korean Journal of Pharmacognosy
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    • v.41 no.1
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    • pp.54-57
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    • 2010
  • A reversed phase HPLC method was developed to determine the major components of Psoralea corylifolia, psoralen, isopsoralen, bakuchiol, and corylin. Quantitative analysis of the above compounds was performed by C-18 column using a gradient solvent system of acetonitrile and water with UV detection at 310 nm. The comparison of contents of psoralen, isopsoralen, bakuchiol, and corylin in psoraleae semen and the processed psoraleae semen was also investigated. In result, processed psoraleae semen showed more amounts of psoralen, isopsoralen, and corylin with 1.6, 4.3, and 1.3 mg/g, respectively, except bakuchiol (66.98 mg/g) while psoraleae semen showed 0.53, 1.56, 1.0, and 76.3 mg/g of psoralen, isopsoralen, corylin, and bakuchiol, respectively.

The Structural Change and Hand of Cellulosic Fiber treated with N-methylmorpholine-N-oxide (N-Methylmorpholine-N-Oxide 처리에 의한 셀룰로오스 직물의 구조변화와 태분석)

  • 조규민;강건우;임용진;김미경;김태경;이혜정
    • Textile Coloration and Finishing
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    • v.15 no.4
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    • pp.43-50
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    • 2003
  • N-methylmorpholine-N-oxide(NMMO) is recently hewn as a solvent dissolving cellulose to produce a new regenerated cellulosic fiber, lyocell. In this study, four kinds of cellulosic fibers (lyocell, regular cotton, treated cotton with 50% and 75% NMMO aqueous solution) was examined and compared in terms of mechanical properties and dyeability. The swelling of cotton treated with NMMO aqueous solution is higher than that of cotton treated with water. In dyeing rate, the cotton treated with NMMO was faster than regular cotton. NMMO treatment decreased the crystallinity of cotton fabrics and improved their softness and smoothness.

Standardization of Gentianae Macrophyllae Radix (진교(秦?, Gentianae Macrophyllae Radix)의 품질표준화에 관한 연구)

  • Lee, Kwang-Sup;Lee, Seung-Jae;Kim, Ho-Hyun;Jin, Hee-Ouk;Ham, In-Hye;Whang, Wan-Kyunn
    • Korean Journal of Pharmacognosy
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    • v.32 no.4 s.127
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    • pp.287-291
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    • 2001
  • The Radix of Gentiana macrophylla (Gentianaceae) has been used for dispelling wind-damp, relaxing the sinews, and clearing heat from deficiency. In order to evaluate its quality, the method for the quantitative determination of gentiopicroside as standard compound has been developed. Gentiopicroside was a major compound of Gentianae Macrophyllae Radix. It was analyzed by HPLC using 30% MeOH as a solvent system. The amount of gentiopicroside from Gentianae Macrophyllae Radix was in the range of $2.22{\pm}1.22%\;(n=18)$.

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Inhibitory Effect of a Drug Metabolizing Enzyme CYP3A4 on Spices (향신료의 약물대사효소 CYP3A4 저해효과)

  • Cha, Bae-Cheon
    • Korean Journal of Pharmacognosy
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    • v.34 no.1 s.132
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    • pp.86-90
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    • 2003
  • For the determination of inhibiting cytochrome P450(CYP)3A4 activity, an improvement HPLC method was established by using a new internal standard and solvent system. Moreover, CYP3A4 amount for a optimum reaction of enzyme was determined by a comparative study with a variety concentration of enzyme. Using a established method, inhibitory effect of CYP3A4 that is drug metabolizing enzyme Investigated on EtOAc extracts of 5-class spices. As a result of experiment, EtOAc extract of white pepper (Piper nigrum L.) showed strong inhibitory activity. On a continuous experiment, the fraction 2, 4 and 5 of while pepper extract showed remarkable inhibitory activity. Pipeline, a main constituent of pepper was not included in these fraction. It is suggested that major compounds for the inhibitory activity of white pepper may be other ingredient that is not piperine.

Pancreatic lipase Inhibitory Compound from Apis mellifera venome

  • Kim, Jun-Ran;Kim, Shin-Duk
    • International Journal of Industrial Entomology and Biomaterials
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    • v.16 no.2
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    • pp.57-59
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    • 2008
  • While searching for pancreatic lipase inhibitors, the active compound was found in a methanol extract of Apis mellifera venome. The active compound was isolated by Diaion HP-20 column chromatography, thin layer chromatography and HPLC. The active compound is stable to the extreme pH and heat. There is no loss of activity both in acidic and alkaline solution in the pH range of 2 to 11 by heating for 15 minutes at $90^{\circ}C$. The rf value of the compound was 0.51 at TLC with butanol : methanol: water (4:1:2) solvent system. The molecular weight of the compound was determined to be 293 by EI-MS.

A Study on the Scientific Conservation of Buried-Fabrics form old Tombs -cleaning and ironing- (출토직물의 과학적 보존 처리에 관한 연구 -세탁방법과 다림질 방법-)

  • 배순화;이미식
    • Journal of the Korean Society of Clothing and Textiles
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    • v.23 no.7
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    • pp.987-997
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    • 1999
  • The purpose of this study was finding out the appropriate cleaning method for buried fabrics from old tombs focusing on the conservation of textiles. Cleaning effects and physical properties change depending on cleaning method have been analysed, The following results were obtained from this study : 1. Wet cleaning showed better effect on the cleaning of fabrics compared to solvent cleaning which meant more water-soluble soils existed than oily soils. 2. All the cleaning methods used did not cause any distorsion or shrinkage to the fabrics because fabrics had been stabilized for a long time 3. Addition of detergent to cleaning system decreased the friction of fiber during cleaning rocess so that the damage of fabrics could be minimized., 4. Ironing is an undesirable process because heat remarkably weakened fibers.

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