• Title/Summary/Keyword: methyl ester

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Potential of Epicoccum purpurascens Strain 5615 AUMC as a Biocontrol Agent of Pythium irregulare Root Rot in Three Leguminous Plants

  • Koutb, Mostafa;Ali, Esam H.
    • Mycobiology
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    • v.38 no.4
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    • pp.286-294
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    • 2010
  • Epicoccum purpurascens stain 5615 AUMC was investigated for its biocontrol activity against root rot disease caused by Pythium irregulare. E. purpurascens greenhouse pathogenicity tests using three leguminous plants indicated that the fungus was nonpathogenic under the test conditions. The germination rate of the three species of legume seeds treated with a E. purpurascens homogenate increased significantly compared with the seeds infested with P. irregulare. No root rot symptoms were observed on seeds treated with E. purpurascens, and seedlings appeared more vigorous when compared with the non-treated control. A significant increase in seedling growth parameters (seedling length and fresh and dry weights) was observed in seedlings treated with E. purpurascens compared to pathogen-treated seedlings. Pre-treating the seeds with the bioagent fungus was more efficient for protecting seeds against the root rot disease caused by P. irregulare than waiting for disease dispersal before intervention. To determine whether E. purpurascens produced known anti-fungal compounds, an acetone extract of the fungus was analyzed by gas chromatography mass spectrometry. The extract revealed a high percentage of the cinnamic acid derivative (trimethylsiloxy) cinnamic acid methyl ester. The E. purpurascens isolate grew more rapidly than the P. irregulare pathogen in a dual culture on potato dextrose agar nutrient medium, although the two fungi grew similarly when cultured separately. This result may indicate antagonism via antibiosis or competition.

Molecularly Imprinted Polymers Having Amidine and Imidazole Functional Groups As an Enzyme-Mimetic Catalyst for Ester Hydrolysis

  • Chen, Wen;Han, Dong-Keun;Ahn, Kwang-Duk
    • Macromolecular Research
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    • v.10 no.2
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    • pp.122-126
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    • 2002
  • A molecularly imprinted polymer (MIP) having both amidine and imidazole functional groups in the active site has been prepared using p-nitrophenyl phosphate as a transition state analogue (TSA). The imprinted polymer MIP with amidine and imidazole found to have the highest hydrolysis activity compared with other MIPs with either amidine or imidazole groups only. It is postulated a cooperative effect between amidine and imidazole in the hydrolysis of p-nitrophenyl methyl carbonate (NPMC) as a substrate when both groups were arranged in proximity by molecular imprinting. The rate enhancement of the hydrolysis by MIP was 60 folds over the uncatalyzed solution reaction and two folds compared with the control non-imprinted polymer CPI having both functional groups. The enzyme-mimetic catalytic hydrolysis of p-nitrophenyl acetate by MIP was evaluated in buffer at pH 7.0 with $K_{m}$ of 1.06 mM and $k_{cat}$ of 0.137 $h^{-1}$ . . .

향신료의 활성산소 포촉인자

  • 정신교
    • Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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    • 1993.12a
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    • pp.10-11
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    • 1993
  • 기저상태의 산소분자는 비교적 안정하지만 생체ㅇ내외에서 물리적, 화학적으로 활성화 되어 $O_{2}$, $^{1}O_{2}$, OH, $H_{2}O_{2}$ 등의 활성산소종을 생성하며, 생체의 지질, 단백질, 핵산 당등의 분자에 산화적 상해를 초래하여 노화, 암, 순환기, 호흡기 게통의 질환과 식품의 품질열화에 관여하는 것으로 알려져 있다. 따라서 본인은 식품의 맛, 향기, 색 등을 부여하는 고유의 기능 외에도 방부제, 한방약으로 널리 이용되고 오고 있는 51종의 향신료를 대상으로 활성산소포촉활성을 조사하고 나아가 활성물질을 분리, 정제 및 동정함으로 향신료의 새로운 기능을 밝히고 신약 개발의 기초적 자료를 제시하고저 한다. Fenton 반응을 이용하여 2-deozyribose 산화법과 sodium benzoic acid 수산화법으로 51종의 향신료의 OH 포촉활성을 검색한 결과, Cruciferae과의 nustard 류, Labiatae과의 thyme, saga, savory, oregano, Myrtaceae과의 clove, allspice 가 1ug/ml 농도에서 50%이상의 포촉활성을 나타내었으며 그중 mustard 류는 같은 농도에서 거의 90%이상의 활성을 나타내었다. 활성물질의 분리 및 정제는 Amberlite XAD-2 갈럼과 preparative-HPLC를 이용 하였으며, EI, FAB-MS, IR, $^{1}H$, $^{13}C-NMR$, Cosy-NMR로 그 화학적 구조를 동정하였다. Brown mustard에서 동정된 4-hydroxy-3,5-dimethoxy cinnamic acid Methyl ester는 0.42$\mu$ mol 농도에서 90% 이상의 OH 포촉활성을 나타내어 이를 diazomethane 반응으로 조제하였으며 white mistard에서는 4-hydroxy-3,5-dimethoxy cinnamoyl choline을 동정하였다.

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Isolation and characterization of 4-chlorophenoxyacetic acid-degrading bacteria from agricultural soils

  • Chung, Min-Jae;Shin, Se-Young;Park, Yong-Keun;Min, Kyung-Hee;Ka, Jong-Ok
    • Journal of Microbiology
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    • v.35 no.2
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    • pp.117-122
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    • 1997
  • Several dominant 4-CPA-degrading bacteria were isoalted from agricultural soils. Most of the isolates were identified as Burkholderia species by fatty acid methyl ester (FAME) analysis, but they were idstinct in chromosomal patterns obtained by PCR amplification of repetitive extragenic palindromic (REP) sequences. These strains were generally restricted in their substrate utilization capabilities. The 4-CPA degradative enzymes were idnducible by 4-CPA and some isolates appeared to mineralize 4-CPA via formation of 4-chlorophenol and 4-chlorocatechol as intermediates during its biodegradation pathway. Plasmid DNAs were not detected from most of the isoaltes and their 4-CPA genes wer on the chromosomal DAN. The 4-CPA degradation patterns in axenic cultures and natural soils varied depending on the strains and soils. The inoculation of 4-CPA degraders much improved the removal of 4-CPA from the 4-CPA treated soils.

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Immunomodulatory Effects of ZYM-201 on LPS-stimulated B Cells

  • Lee, Ye Eun;Kim, Soochan;Jung, Woong-Jae;Lee, Hyung Soo;Kim, Mi-Yeon
    • IMMUNE NETWORK
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    • v.14 no.5
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    • pp.260-264
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    • 2014
  • ZYM-201 is a methyl ester of triterpenoid glycoside from Sanguisorba officinalis which has been used for treatment of inflammatory and metabolic diseases. In this study, immunomodulatory effects of ZYM-201 on B cells were examined in vitro and in vivo. When splenocytes were activated with lipopolysaccharide (LPS), the major population which had shown an increase in cell numbers was B cells. However, when the B cells were treated with ZYM-201 after LPS activation, their cell numbers and the expression of major costimulatory molecules, CD80 and CD86, were decreased. Furthermore, the effect of LPS, which induces activation of NF-${\kappa}B$, was abolished by ZYM-201: LPS-stimulated B cells showed decrease of phosphorylation after treatment of ZYM-201. The same results were shown in vivo experiments. These results suggest that ZYM-201 may play a role in the modulation of inflammatory responses through inhibiting NF-${\kappa}B$ activation and downregulating the expression of costimulatory molecules on B cells.

Solution-processed Polymer Tandem Cells Using Nano Crystalline $TiO_2$ Interlayer ($TiO_2$ 나노 입자의 중간 전극을 이용한 직렬 적층형 유기 태양 전지)

  • Chung, Won-Suk;Ju, Byeong-Kwon;Ko, Min-Jae;Park, Nam-Gyu;Kim, Kyung-Kon
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2008.11a
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    • pp.444-444
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    • 2008
  • For the polymer tandem cell, simple and advantaged solution-based method to electron transport intermediate layer is presented which are composed $TiO_2$ nanoparticles. Device were based on a regioregular Poly(3-hexylthiophene)(P3HT) and [6,6]-phenyl $C_{61}$ butyric acid methyl ester($PC_{60}BM$) blend as a donor and acceptor bulk-heterojunction. For the middle electrode interlayer, the $TiO_2$ nanoparticles were well dispersed in ethanol solution and formed thin layer on the P3HT:PCBM charge separation layer by spin coating. The layer serves as the electron transport layer and divides the polymer tandem solar cell. The open-circuit voltage (Voc) for the polymer tandem solar cells was closed to the sum of those of individual cells.

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Study of the Electrochemical Redox Characteristics of Some Triazolopyrimidines

  • Maghraby, A.A. El;Elenien, G.M. Abou;Shehata, K.I.
    • Journal of the Korean Electrochemical Society
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    • v.10 no.3
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    • pp.159-168
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    • 2007
  • An electrochemical study related to the redox characteristics of Ethyl-3-acetyl-6-methyl-1, 4-diphenyl-4, 3a-dihydro-1, 3, 4-triazolino[3, 4-a] pyrimidine-5-carboxylate ester and its derivatives (1a-f) and (2a-e) in nonaqueous solvents such as 1, 2-dichloroethane (DCE), dichloromethane (DCM), acetonitrile (AN), dimethylsulphoxide (DMSO) and tetrahydrofurane (THF) using $0.1\;mol\;dm^{-3}$ tetrabutylammonium perchlorate (TBAP) as a supporting electrolyte at platinum, glassy carbon and gold electrodes, has been performed using cyclic voltammetry (CV). Controlled potential electrolysis (CPE) is also carried out to elucidate the course of different electrochemical reactions through the separation and identification of the intermediates and final electrolysis products. The redox mechanism is suggested and proved. It was found that all the investigated compounds in all solvents are oxidized in a single irreversible one electron donating process following the well known pattern of the EC-mechanism to give a dimer. On the other hand, these compounds are reduced in a single irreversible one electron step to form the anion radical, which is basic enough to proton from the media forming the radical which undergoes tautomerization and then dimerization processes to give also another bis-compound through N-N linkage formation.

Study on the Mechanism of Vascular Relaxation of Ethanol Extract of Persicaria Perfoliata H. Gross (하백초 에탄올 추출물의 혈관이완 기전에 대한 연구)

  • Kim, Hye-Yoom;Choi, Byung-Sun;Choi, Eun-Hee;Cui, Hao-Zhen;Kang, Dae-Gill;Lee, Ho-Sub
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.23 no.2
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    • pp.389-396
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    • 2009
  • The ethanol extract of Persicaria perfoliata (EPP) induced relaxation of the phenylephrine-precontracted aorta in a dose-dependent manner, which was abolished by removal of functional endothelium. Pretreatment of the aortic tissues with NG-nitro-L-arginine methyl ester (L-NAME) or 1H-[1,2,4}-oxadiazole-[4,3-${\alpha}$)-quinixalin-1-one (ODQ) inhibited the relaxation induced by EPP. However, EPP-induced relaxation was not blocked by pretreatment with indomethacine, glibenclamide, tetraethylammonium (TEA), atropine, or propranolol. Incubation of endothelium-intact thoracic aortic ring with EPP increased the production of cGMP, which was also blocked by pretreatment with L-NAME or ODQ. These results suggest that EPP dilates vascular smooth muscle via endothelium-dependent NO/cGMP signaling.

Studies on the Synthesis of N-alkyl-N-acyl glucamines (N-alkyl-N-acyl glucamines의 합성에 관한 연구)

  • Ahn, Ho-Jeong;Cho, Kyu-Suk
    • Applied Chemistry for Engineering
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    • v.7 no.1
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    • pp.171-176
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    • 1996
  • The easily biodegradable nonionic surfactant of glucamide(N-alkyl-N-acyl glucamine) was synthesized by the two-step reaction. The first step was the amination between alkylamine and glucose in methanol. Then, alkyl glucamines were obtained by reduction using Ni catalyst under the high pressure with 86~93% of reaction yield. The second step was the synthesis of glucamide from alkyl glucamine and fatty acid methyl ester in methanol under the alkali catalytic condition while refluxing the solvent. The reaction yield of this step was 84~95% except the benzyl glucamine, which the reaction yield was 50~70%. The molecular structure of four kinds of alkyl glucamine and 16 kinds of glucamide with different alkyl and acyl groups was studied by IR, MS and NMR.

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Screening of Conjugated Linoleic Acid Producing Lactic Acid Bacteria from Fecal Samples of Healthy Babies

  • Ham, J.S.;In, Y.M.;Jeong, S.G.;Kim, J.G.;Lee, E.H.;Kim, H.S.;Yoon, S.K.;Lee, B.H.
    • Asian-Australasian Journal of Animal Sciences
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    • v.15 no.7
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    • pp.1031-1035
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    • 2002
  • This study was carried out to obtain conjugated linoleic acid (CLA) producing lactic acid bacteria for further study on the enzymes related to the production of CLA which has gained considerable attention and on the development as a probiotic culture. Total 34 lactic acid bacteria were isolated from 19 feces samples of healthy babies. CLA forming ability was measured spectrophotometrically by the modification of linoleate 12-cis, 11-trans-isomerase activity measuring method, and CLA of the cultures were extracted, methylated, and examined by HPLC analysis. CLA methyl ester of only one culture showing the highest value of CLA forming ability could be detected by HPLC analysis. The culture was found to be Gram positive, rods and catalase negative. It grows at $45^{\circ}C$ but not at $15^{\circ}C$, and was identified to be Lactobacillus fermentum on the basis of the biochemical characteristics and the utilization of substrates. These results provide an efficient experimental method to screen CLA producing lactic acid bacteria.