• Title/Summary/Keyword: methyl ester

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Stimulatory Effect of Ginseng Saponin on Endogenous Production of Nitic Oxide

  • Kim, Hye-Young
    • Proceedings of the Ginseng society Conference
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    • 1998.06a
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    • pp.199-207
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    • 1998
  • Ginseng saponin (G5) purified from Panax ginseng, increase renal blood flow in rats. Nitric oxide (NO) is thought to be a substance endogenously released by G5 in preconstricted lungs and cultured endothelial cells. The present study aims to determine whether G5 could stimulate endogenous 1'elease of NO in rat kidney and urine levels of the stable NO metabolites, nitrite (NO,) and nitrate (NO,) and urinary COMP levels were measured 8 hr after a single intraperitoneal injection of GS (200 mg/kg) Into rats. The effects of the WO synthesis inhibitor, Nu-nitro-L-arginine methyl ester, .1nd the NO precursor, L-arginine, on the G5-induced changes were also determined. The activity of NO synthase, as determined by conversion of ('"C)-L-arginine to ('"C)-L-citrulline, in whole kidney, glomeruli and cortical tubules were also investigated. A single injection of GS resulted in endogenous production of NO as reflected by increase in serum and urine levels of N021N03 and urinary cGMP levels, which were inhibited by the addition o ( N-nitro-L-arginine methyl ester and restored fly L-arginine. GS also stimulated the activity of NO synthase in whole kidney as well as glomeruli and cortical tubules, and Nu-nitro-L-arginine methyl tilter significantly prevented this increase. In conclusion, GS stimulates endogenous NO production and thus, may play a protective role 1 11 the kidney by modulating renal blood flow.

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Chromatographic Enantiomer Separation and Determination of Optical Purity for α-Amino Acid Esters as 9-Anthraldimine Derivatives Using Polysaccharide Based Chiral Columns (다당 유도체를 기초로 한 키랄 컬럼에서 아미노산 에스테르의 안트르알디민 유도체의 광학분리 및 광학순도 측정)

  • Huang, Hu;Jin, Jing-Yu;Lee, Won-Jae
    • KSBB Journal
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    • v.26 no.2
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    • pp.139-142
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    • 2011
  • The chromatographic enantiomer separation of 9-anthraldimine derivatives of ${\alpha}$-amino acid methyl and ethyl esters on four polysaccharide based chiral columns was performed. The 9-anthraldehyde Schiff base derivatives of ${\alpha}$- amino acid esters were readily synthesized by stirring the ${\alpha}$- amino acid ester hydrochloride salts with 9-anthraldehyde in the presence of 1,8-diazabicyclo [5.4.0]undec-7-ene as a base and anhydrous $MgSO_4$. Chiralcel OD or Chiralcel OD-H showed the greatest enantiomer resolution of 9-anthraldimine derivatives of ${\alpha}$-amino acid methyl and ethyl esters. The L-enantiomers of all the analytes were preferentially retained on Chiralcel OD or Chiralcel OD-H. This analytical method was applied in the determination of optical purities of several commercially available D- or L-${\alpha}$-amino acid methyl esters.

Fatty Acid Methyl Ester (FAME) Technology for Diagnosing Nocardia Foaming in Activated Sludge (활성슬러지내 Nocardia 거품현상 진단을 위한 Fatty Acid Methyl Ester (FAME) 기술)

  • Lee, Jae Woo;Kim, Il Kyu;Lee, Seok Hun;Ahn, Kyu-Hong;Cha, Daniel K.
    • Journal of Korean Society of Water and Wastewater
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    • v.18 no.4
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    • pp.480-485
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    • 2004
  • Fatty acid methyl ester (FAME) technology was evaluated as a monitoring tool for quantification of Nocardia amarae causing a nuisance foaming problem in activated sludge process. The identified signature peak was 19:1 alcohol as a reliable unique peak to N. amarae. Chemostat study revealed that the distribution and quantity of fatty acid peaks were dependent on the growth stage of Nocardia. The FAME results were similar for two relatively high dilution rates; however, the amounts of signature peaks extracted from the 4 and 6 day cultures were significantly higher. This dependence of signature peaks on the physiological state of the organism may be a useful information to assess the health of microbial populations in activated sludge. A laboratory scale batch foaming potential experiment provided a critical foaming level depending on Nocardia population. This critical Nocardia level determined in this study was in terms of either the threshold filament intersections number or the threshold signature FAME amount. The threshold peak area of signature FAME (19:1 alcohol) and corresponding filament counts were 430PA/mg VSS and $1.45{\times}10^6$ intersections/g VSS, respectively. The threshold signature FAME level could be effectively applied as a criterion for diagnosing foam occurrence in activated sludge system.

Chemical Structures of the Compounds Isolated from the Edible Mushroom Sarcodon aspratus (능이버섯(Sarcodon aspratus)으로부터 분리한 저분자 화합물의 화학구조)

  • Kang, Hee-Chol;Yun, Bong-Sik;Yu, Seung-Hun;Yoo, Ick-Dog
    • Applied Biological Chemistry
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    • v.43 no.4
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    • pp.298-302
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    • 2000
  • In our investigation on chemical constituents of edible mushrooms, seven compounds I-VII have been isolated from the methanolic extract of the fruit body of Sarcodon aspratus. The methanolic extract was separated by solvent partition, silica gel column chromatography and Sephadex LH-20 column chromatography, and compounds I-VII were finally purified by preparative HPLC or TLC. Their structures were assigned as 4-hydroxybenzoic acid methyl ester, 4-hydroxybenzaldehyde, cyclo(Ala-Pro), adenosine, nicotinamide, BL V, linoleic acid, respectively, on the basis of mainly $^1H\;NMR$ spectra.

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Chiral Separation of Lactic Acid in Culture Media and Cells of Lactobacillus delbrueckii subsp. lactis as O-Pentafluoropropionylated (S)-(+)-3-Methyl-2-Butyl Ester by Achiral Gas Chromatography-Mass Spectrometry

  • Paik, Man-Jeong;Nguyen, Duc-Toan;Yoon, Jae-Hwan;Chae, Han-Seung;Kim, Kyoung-Rae;Lee, Gwang;Lee, Pyung-Cheon
    • Bulletin of the Korean Chemical Society
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    • v.32 no.7
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    • pp.2418-2422
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    • 2011
  • The enantiomeric separation of lactic acid for its absolute configuration has become important task for understanding its biological origin and metabolic process involved in the formation of lactic acid. It involves the conversion of enantiomers as diastereomeric O-pentafluoropropionylated (S)-(+)-3-methyl-2-butyl ester and the direct separation by gas chromatography-mass spectrometry on a achiral capillary column. The (R)- and (S)-lactic acids were completely separated with a high resolution of 1.9. The newly developed method showed good linearity (r ${\geq}$ 0.999), precision (% relative standard deviation = 3.4-6.2), and accuracy (% relative error = -7.7-1.4) with the detection limit of 0.011 ${\mu}g/mL$. When the method was applied to determine the absolute configuration of lactic acid in Lactobacillus delbrueckii subsp. lactis 304 (LAB 304), the composition (%) of (R)-lactic acid in the cell pellet and in the culture medium were $89.0{\pm}0.1$ and $78.2{\pm}0.4$, respectively. Thus, it was verified that the present method is useful for the identification and composition test of lactic enantiomers in microorganisms.

Isolation and Identification of Lipids from the Roots of Canna generalis (칸나(Canna generalis)의 뿌리로부터 지질화합물의 분리.동정)

  • Bang, Myun-Ho;Song, Myoung-Chong;Lee, Dae-Young;Yang, Hye-Jung;Han, Min-Woo;Baek, Nam-In;Lee, Youn-Hyung
    • Applied Biological Chemistry
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    • v.49 no.4
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    • pp.339-342
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    • 2006
  • Canna generalis was extracted with 80% aqueous MeOH, and the concentrated extract was partitioned with EtOAc, n-BuOH and $H_2O$, successively. from the EtOAc and n-BuOH fractions, four compounds were isolated through the repeated silica gel and ODS column chromatographies. From the results of physico-chemical data including NMR, MS and IR, the chemical structures of the compounds were determined as $\beta$-sitosterol(1), linoleic acid methyl ester(2),1-O-oleoyl-2-O-linoleoyl-3-O-$\beta$-D-galactopyranosyl-sn-glycerol(3), and daucosterol(4). They were the first to be isolated from Canna generalis.

[6,6]- phenyl-C85 Butyric Acid Methyl Ester 나노입자를 포함한 나노복합체를 사용하여 제작한 비휘발성 메모리의 전기적 성질과 안정성

  • Park, Hun-Min;Lee, Min-Ho;Yun, Dong-Yeol;Kim, Tae-Hwan
    • Proceedings of the Korean Vacuum Society Conference
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    • 2011.08a
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    • pp.274-274
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    • 2011
  • 유기물/무기물 나노복합체를 이용하여 제작한 비휘발성 메모리 소자는 저전력 구동과 간단한 공정과 같은 장점 때문에 많은 연구가 진행되고 있다. 무기물 나노 입자를 포함한 고분자 박막을 사용한 비휘발성 메모리 소자에 대한 연구는 많이 진행되었으나, [6,6]- phenyl-C85 butyric acid methyl ester (PCBM) 나노 입자가 고분자 박막에 분산되어 있는 나노복합체를 사용하여 제작한 메모리 소자의 전기적 특성과 안정성에 대한 연구는 미흡하다. 본 연구에서는 PCBM 나노 입자가 poly (methylmethacrylate) (PMMA) 박막 안에 분산되어 있는 나노복합체를 사용한 메모리 소자를 제작하여 전기적 특성 및 안정성에 대하여 관찰하였다. PCBM 나노 입자를 PMMA와 함께 용매인 클로로벤젠에 용해한 후에 초음파 교반기를 사용하여 두 물질을 고르게 섞었다. 전극이 되는 indium-tin-oxide 가 성장된 유리 기판 위에 PCBM과 PMMA가 섞인 용액을 스핀 코팅한 후, 열을 가해 용매를 제거하여 PCBM입자가 PMMA에 분산되어 있는 나노복합체 박막을 형성하였다. 형성된 나노복합체 박막 위에 상부 전극으로 Al을 열증착하여 비휘발성 메모리 소자를 완성하였다. 제작된 소자의 전류-전압 측정 결과는 큰 ON/OFF 전류비율을 보여주었다. PCBM 나노입자를 포함하지 않은 소자에서는 메모리 특성이 나타나지 않았기 때문에 PCBM 나노 입자가 비휘발성 메모리 소자의 기억 특성을 나타내는 저장매체가 됨을 알 수 있었다. 전류-시간 측정 결과는 소자의 ON/OFF 전류 비율이 시간이 지남에 따라 큰 감쇠 현상 없이 104 sec 까지 지속적으로 유지됨을 알 수 있었다. 제작된 각각의 메모리 소자의 ON/OFF 전류 비율 결과는 103 이상의 일정한 값이 측정되어 제작된 소자의 안정성을 보여주었다.

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Isolation of Melanogenesis Inhibitors from Cnidii Rhizoma (천궁으로부터 멜라닌 생성억제 물질 분리)

  • Lee, Yun-Kyoung
    • Journal of dental hygiene science
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    • v.4 no.2
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    • pp.81-84
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    • 2004
  • Gingival hyperpigmentation may cause esthetic problems and embarrassment. Especially in patients with a gummy smile. Melanin pigmentation is related to estiologic factor such as hormon, systemic factor, drug, smoking and gingival inflamation. During our search for new inhibitory components on melanogenesis from natural resources, MeOH extracts of more than 100 higher plants were tested for the inhibitory effect on melanogenesis in cultured B-16 mouse melanoma cell lines, and methylene chloride soluble part extract of Cnidii Rhizoma MeoH extraction was found to have potent activity. Cnidii Rhizoma, the root of Cnidium officinale Makino (Umbelliferae), is used for the treatment of abdominal pain, arthralgia, headache, hypertension, intestinal colic and for menstrual disorders and uterine cramps for its anti-blood stagnation effect. Two compounds were isolated and their chemical structures were determined as linoleic acid methyl ester(1), 1,3-dilinoleoyl-2-stearoyl glycerol(2), on the basis of physical and spectral data.

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Attractiveness of Sex Pheromone of the Large Black Chaefer, Holotrichia parallela (Motschulasky) (Coleoptera : Scarabaeidae), in Potato Field (고구마 재배지에서 성페로몬에 의한 큰검정풍뎅이 ((Holotrichia parallela (Motschulasky) (Coleoptera: Scarabaeidae)) 유인 효과)

  • Choi, Man-Young;Paik, Chae-Hoon;Seo, Hong-Yul;Lee, Geon-Hwi;Kim, Jae-Duk;Roitberg, Bernard D.;Gries, Gerhard
    • Korean journal of applied entomology
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    • v.45 no.2 s.143
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    • pp.169-172
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    • 2006
  • Sex pheromone blends of large black chafer, Holotrichia parallela (Motschulasky), which consist of a major component L-isoleucine methyl ester (LIME) and a minor component (R)-(-)-linalool, showed different attractiveness depending on the mixing ratios of the two components in potato fields in South Korea. The best ratio for H. parallela attraction was 2.5:1 of LIME and (R)-(-)-linalool. The attraction ability of pheromone traps bated with 2.5:1 ratio did not drop up to 14m, but significantly decreased at 21m from H parallela release point. Korean population of H. parallela showed almost same periodical activity to sex pheromone with that reported in Japan, which showing a circabidian periodicity of 48h cycle.

Synthesis of a Sulfonic Acid Analogues of Peptides (Tauryl-L-Histidine) (Tauryl-L-Histidine 의 合成)

  • Park, Won-Kil
    • Journal of the Korean Chemical Society
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    • v.5 no.1
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    • pp.38-41
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    • 1961
  • By varying groups on biologically active molecules, it is possible to produce analogues which sometimes inhibit the action of the parent compound. Such is true of taurine(${\beta}$-amino-ethane sulfonic acid)as an analogue of ${\beta}$-alanine and of pantoyl taurine for pantothenic acid. It seemed possible that the sulfonic acid analogues of amino acids built into peptides might possibly produce inhibition of the parent peptide. Tauryl-L-histidine was selected to prepare as an analogue of carnosine(${\beta}$-alanyl-L-histidine). There were several reasons for this choice. Camosine causes a slight contraction of isolated uterine muscle and inhibition of this action can be easily tested. Also, taurine, being a ${\beta}$-amino sulfonic acid, is much more stable than the ${\beta}$-amino sulfonic acids. Phthalyl tauryl-L-histidine methyl ester was prepared by condensing phthalyl tauryl chloride with histidine methyl ester in chloroform. The yields were quite low possibly due to reaction between the acid chloride and the imidazole of histidine. Approximately 50 per cent yield of crude amorphous product was obtained, but upon purification by crystallization they yielded only 25 percent of a pure product. The methyl ester was removed by acid hydrolysis to prevent partial cleavage of the phthalyl group. Crystalline tauryl histidine was then obtained from this acid by removal of the phthalyl group by hydrazinolysis. Tests for inhibition were carried out by comparing the action of camosine on isolated uterine muscle before and after tauryl histidine had been added to the bath surrounding the muscle strip. Only in very high relative concentrations of tauryl histidine was there any demonstrable inhibition.

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