• 제목/요약/키워드: Methanol synthesis

검색결과 370건 처리시간 0.022초

초두구 추출물의 α-glucosidase 활성 억제에 의한 항바이러스 활성 (Methanol Extract of Alpinia katsumadai Hayata has Anti-viral Activity by Inhibition of α-glucosidase)

  • 이도승;부경환;김영천;이진만;김성철;이왕식;류기중;이동선
    • Journal of Applied Biological Chemistry
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    • 제57권2호
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    • pp.179-182
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    • 2014
  • ${\alpha}$-glucosidase 활성을 저해하는 초두구 메탄올 추출물의 항바이러스 활성을 연구하였다. Newcastle disease virus (NDV) 감염된 baby hamster kidney (BHK) 세포에서 Syncytium (합포체) 형성은 세포막 표면으로의 수송된 바이러스 당단백질 hemagglutinin-neuramidase (HN)에 의해 일어난다. 초두구 추출물$IC_{50}$ $25{\mu}g/mL$) 처리된 세포에서 바이러스 당단백질의 수송과 함께 합포체 형성이 저해되었다. 또한 $IC_{50}$ 농도에서는 세포 내에서 당단백질 생합성은 저해되지 않으며 당단백질의 수송을 저해하는 것으로 추론된다.

Synthesis and Characterization of ${\omega}-Sulfonated$ Polystyrene-stabilized Cadmium Sulfide Nanoclusters

  • Jin Yong Hyun;Kim Jungahn;Im Seung Soon
    • Macromolecular Research
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    • 제12권6호
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    • pp.604-607
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    • 2004
  • We report an important and useful method for preparing ${\omega}-sulfonated$ polystyrene-stabilized cadmium sulfide (CdS) nanoclusters. The ${\omega}-sulfonated$ polystyrene $(M_n\;=\;5000\;g/mol)$ was prepared successfully through chain-end sulfonation of poly(styryl)lithium using 1,3-propanesultone; the resulting polymer was used successfully as a polymeric stabilizing agent for the preparation of semiconductor CdS nanoclusters by reduction of cadmium acetate in a mixture of toluene and methanol (9:1, v/v). The nanoclusters that formed were characterized by a combination of transmission electron microscopy, X-ray diffraction, and UVN is spectroscopic analysis. The ${\omega}-sulfonated$ polystyrene-stabilized CdS nanoclusters synthesized in this study exhibited the cubic phase (zinc-blende phase) structure in the range of 2-8 nm.

유기 화합물을 이용한 MPECVD에 의한 다이아몬드 박막 합성 (The Synthesis of Diamond Thin Films by MPECVD Using Organic Compounds)

  • 구자춘;오정섭;황기웅
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1990년도 추계학술대회 논문집 학회본부
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    • pp.97-100
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    • 1990
  • Diamond thin films were synthesized by the MPECVD (Microwave Enhanced Chemical Deposition) using the mixture of the hydrogen and organic compounds($CH_3COCH_3$, $CH_3OH$). In X-ray Diffraction, the d values of all the deposits on the Si substrates with the experimental conditions coincide with those of natural diamond in POD (Powder Diffraction Data). The changes of the morphology of all the deposits were examined by SEM. The amount of amorphous carbon or graphite in the diamond films were increased as the acetone concentration was increased. The morphology of the diamond particles can be changed from ball-like to euhedral by adding the small amount of the methanol in the reaction gases of the high acetone concentration.

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고순도 지르코니아 분말의 합성 및 그 특성 (조립방법에 따른 성형 및 소결 특성) (The Synthesis of High-purity Zirconia Powders and Its Properties (Compaction and Sintering Behaviro as a Function of Granulation Methods))

  • 김환;이종국;김주영;황규홍
    • 한국세라믹학회지
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    • 제25권4호
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    • pp.357-363
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    • 1988
  • Ccompaction and sintering behavior of highly pure PSZ powders were investigated by laying the stress on the granulation processes. The particle size of coprecipitated PSZ powder was so fine that the agglomeration was severely formed during drying and calcing step and by this agglomeration differential sinering was occurred. The methanol dispersion of precipitates was the good method of avoiding severe agglomeration formed during drying process because of small surface tension than water. But perfect deagglomeraton was not possible due to high surface area of powders. So homogenization by granulation was needed, and among the method spray granulation was the most desirable to obtain homogeneous compacts and subsequent flaw-free ceramics.

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Mycelial Growth Enhancement in Liquid Cultivation of Hericium erinaceus

  • 김민석;서정식;홍억기
    • 한국생물공학회:학술대회논문집
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    • 한국생물공학회 2003년도 생물공학의 동향(XII)
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    • pp.236-239
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    • 2003
  • 생물반응기를 이용한 회분배양에서 균체량 생산에 있어서 조건은 200 rpm, 1 vvm 으로 선정하였으며, 이때 균체량은 11 g/L이었고, polysaccharide는 0.6 g/L이었다. 또한 pH를 초기 pH인 5.5로 고정하여 배양한 결과 pigment들로 인한 균사체의 활성이 떨어지는 것으로 나타났다 균체량을 증가시키기 위한 최적의 회분배양 조건에서는 초기 200 rpm으로 배양을 시작하여 300 rpm으로 증가시키고 glucose 5 g/L를 간헐적으로 첨가함으로써 균체량은 24.2 g/L, polysaccharide는 2.2 g/L로 나타났다. 또한 erinacine A의 분석은 HPLC를 사용하였으며 배양 4.5일째 균사체로부터 추출하여 mobile phase를 Methanol/water (9:1)로 flow rate은 0.7 ml/min으로 실험한 결과 erinacine A는 0.4 mg/g cell 로 측정되었다.

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뽕잎추출물이 콜레스테롤 투여 흰쥐의 혈청지질에 미치는 영향 (Antihyperlipidemic Effects of Methanol Extracts from Mulberry Leaves in Cholesterol-Induced Hyperlipidemia Rats)

  • 김선여;이완주;김현복;김애정;김순경
    • 한국식품영양과학회지
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    • 제27권6호
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    • pp.1217-1222
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    • 1998
  • This study was conducted to investigate the effect of mulberry leaves on lipid metabolism in cho lesterol induced hypercholesterolemia rats. The mulberry treatment group showed decreases of serum lipid concentration compared with hyperlipidemic group. Also, Mulberry leaves inhibited the activity of HMG Co A reductase, increased lipase activity. In histopathological examination, abdominal aorta showed no critical lesions with mulberry leaves treatment. These results suggest that hypolipidemic effects of mulberry leaves on rats were the inhibition of cholesterol synthesis and acceleration of cholesterol catabolism in the liver. For human, serum triglyceride contents were more significantly decreased with treatment of mulberry leaves powder.

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Purification and reaction pattern of cephalexin synthesizing enzyme from Acetobacter turbidans

  • Kang, Sang-Moo;Kim, June-Hoe;Kim, Deog-Jung;Kim, Young-Jun
    • 한국미생물생명공학회:학술대회논문집
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    • 한국미생물생명공학회 1986년도 추계학술대회
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    • pp.525.2-525
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    • 1986
  • Cephalexin synthesizing enzyme (${\alpha}$ amino acid ester hydrolase) was partially purified from the culture broth of Acetobacter turbidans ATCC9325 through ammonium sulfate fractionation, DEAE, CM, and Sephacryl S-200 gel filtration. The enzyme has optimum pH 6.0 and temperature, 40$^{\circ}C$ respectively. From the analysis of reaction mixtures by thin layer chromatographic and high performance liquid chromatographic techniques, it was confirmed this enzyme catalyzed simultaneously the following reactions : 1) Synthesis of cephalexin from D-${\alpha}$-phenylglycine methylester (PGM) and 7-amino 3-deacetoxy-cetoxycephalosporanic acid (7-ADCA) 2) Hydrolysis of cephalexin to form 7-ADCA and phenylglycine (PG) 3) Hydrolysis of PGM to form PG and methanol. Base on the above experimental observations, the reaction model of this enzyme was identical with that of the enzyme from Xanthomonas citri.

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Synthesis of 2'-Hydroxydihydrochalcone from Flavone

  • Kim, Mi-Hyang;Shin, Bok-Kyu;Won, Dong-Ho;Han, Jae-Hong
    • Journal of Applied Biological Chemistry
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    • 제50권2호
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    • pp.85-87
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    • 2007
  • To establish the synthetic method for dihydrochalcones as an important bioactive compounds, 2'-hydroxydihydrochalcone has been synthesized from the reduction of flavone in 20% yield. Flavone with five equivalents of ammonium formate in the presence of Pd/C in methanol under $N_2$ atmosphere produced the C-ring opened product. It was characterized by UV-VIS, ESI-MS and $^1H-NMR$ spectroscopy, and identified as 2'-hydroxydihydrochalcone.

고분자(高分子) 계면활성제(界面活性劑)에 관한 연구(硏究) (제(第) 3 보(報));알릴에스테르 ${\alpha}$-술폰 지방산(脂肪酸) 고분자(高分子) 화합물(化合物)의 합성(合成) (Studies on the Polymeric Surfactants (III);Synthesis of Sodium ${\alpha}-Sulfo$ Fatty Acid Allyl Ester Oligomers)

  • 남기대;정노희;노승호
    • 한국응용과학기술학회지
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    • 제6권2호
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    • pp.45-51
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    • 1989
  • Allyl aliphatic carboxylates were synthesized by azotropic reaction with benzene between allyl alcohol and capric acid, lauric acid, myristic acid, palmitic acid or stearic acid respectively. allyl aliphatic carboxylates oligomers were prepared from polymerization giving allyl aliphatic carvboxylates in the presence of potassium persulfate in methanol, and the ${\alpha}-sulfonation$ of these five allyl aliphatic carboxylates oligomers were carried by direct addition of dry sulfur trioxide. Especially, molecular weights of fatty acid alylester oligomers and their sodium salts of ${\alpha}-sulfo$ fatty acid allylester oligomers were measured by boiling point method.

Synthesis and Permeation Characteristics of Zeolite Membranes

  • Kita, Hidetoshi
    • 한국막학회:학술대회논문집
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    • 한국막학회 1997년도 추계 총회 및 학술발표회
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    • pp.5-8
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    • 1997
  • Introduction : Membranes made from inorganic materials are generally superior to organo-polymeric materials in thermal and mechanical stability, and chemical resistance. Among inorganic materials zeolite is a promising candidate for a high performance membrane because of the unique characteristics of zeolite crystals such as molecular sieving, ion exchange, selective adsorption and catalysis. Although there are many recent reportsl on the preparation of zeolitc membranes and the gas permeation through the membranes, only a limited number of publications deal with pervaporation studies. Recently, we have reported a high pervaporation performance of NaA zeolite membrane for the separation of water/organic liquid mixtures. and of NaY zeolite menlbrane for the separation of methanol/MTBE. Here, preparation of zeolite (LTA, ZSM-5 and FAU) membranes and their permeation properties are discussed.

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