• 제목/요약/키워드: anion effect

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Production of superoxide anion, nitric oxide and tumor necrosis factor-$\alpha$ by cultured murine peritoneal leukocytes is inhibited by taurine chloramine

  • Kim, Chaekyun;Park, Eunkyue;Michael R. Quinn
    • 한국응용약물학회:학술대회논문집
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    • 한국응용약물학회 1996년도 춘계학술대회
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    • pp.177-177
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    • 1996
  • Taurine Chloramine (Tau-Cl) inhibits production of nitric oxide(NO) and tumor necrosis factor-alpha (TNF-${\alpha}$) in activated peritoneal macrophages, similar In that previously reported for activated RAW 264.7 cells. In addition, the effect of Tau-Cl and taurine on superoxide anion (O$\_$2/$\^$-/) Production in murine peritoneal exudate polymorphonuclear leukocytes (PMN) was examined. Tau-Cl inhibited O$\_$2/$\^$-/ production in a manner that was dose-dependent and reversible, Taurine also inhibited O$\_$2/$\^$-/ production by stimulated PMN, but at higher concentrations and to a lesser extent than Tau-Cl. The effects of taurine on O$\_$2/$\^$-/ production was attributed to the in vitro formation of Tau-Cl catalyzed by PMN associated halide-dependent myeloperoxidase. In contrast, production of NO and TNF-${\alpha}$ by activated peritoneal exudate macrophages was inhibited by Tau-Cl while taurine was without effect. These data lend support to the notion that Tau-Cl may participate ill the inflammatory responses by modulating production of inflammatory mediators.

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음이온 계면활성제 미셀형성을 이용한 중공사 한외여과막 시스템에서의 코발트(Co)이온 제거 (Removal of Co++ Ion in the Hollow Fiber Ultrafiltration System using Anion Surfactant Micellar Enhancement)

  • 양현수;한광희;최광순
    • 공업화학
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    • 제7권1호
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    • pp.109-117
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    • 1996
  • 음이온 계면활성제의 미셀을 이용하여 한외여과막에서의 금속이온의 제거 기술은 분리공정이 간단하고 상변화가 필요없어 폐수로부터 중금속과 작은 분자량의 분자들을 제거할 수 있는 최근에 발전된 기술이다. 임계미셀농도 이상에서 계면활성제 분자들은 서로 모이고 거대분자 또는 미셀을 형성한다. 양이온의 코발트 이온과 음이온 계면활성제 미셀과의 정전기적인 결합으로 크기가 커진 거대분자가 한외여과막에서 제거되었다. 막투과압력차는 한외여과막에서의 금속의 제거율에 비교적 작은 영향을 끼치는 반면 음이온 계면활성제와 금속염간의 비(S/M)는 상당한 영향을 끼쳤다.

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신남산 유도체III, Benzalacetophenone 유도체에 대한 Thioglycolic acid의 친핵성 첨가반응 메카니즘과 그 반응속도론적 연구 (Cinnamic Acid Derivatives III, The Kinetics and Mechanism of the Nucleophilic Addition of Thioglycolic Acid to Benzalacetophenone Derivatives)

  • 이기창;황용현;박은경;류정욱;이광일
    • 한국응용과학기술학회지
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    • 제7권2호
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    • pp.33-40
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    • 1990
  • The Kinetics of the addition of benzalacetophenone derivatives was investigated by ultraviolet spectrophotometery in 5% dioxane $H_2O$ at $50^{\circ}C$. A rate equation was obtained in wide range of pH. The substituent effects on benzalacetophenone derivatives were studied, and addition were facilitated by electron attracting groups. The final product was benzalacetophenone-${\beta}$-thioglycolic acid synthesized by the addition of thioglycolic acid to benzalacetophenone. On the base of the rate equation, substituent effect, general base effect and final product, the plausible addition mechanism was proposed: Below pH 9.0, only neutral thioglycolic acid molecule was added to the carbon-carbon double bond, and in the range of pH $9.0{\sim}11.0$, neutral thioglycolic acid molecule and thioglycolic acid anion competitively attacted the double bond. By contrast, above pH 11.0, the reaction was dependent upon only the addition of thioglycolic acid anion.

Phenazine dioxide 유도체가 간 Xanthine Oxidase 활성에 미치는 영향 (Effect of Phenazine Dioxide Derivatives on the Hepatic Xanthine Oxidase Activity)

  • 강일영;김상렬;김호식;허근
    • 약학회지
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    • 제34권2호
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    • pp.112-116
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    • 1990
  • 8-Acyl-2-hydroxyphenzaine -5, 10-dioxides and 8-acyl-2-aminophenazine-5, 10-dioxides bearing n-butanoyl, n-hexanoyl and n-octanoyl groups were synthesized. It was attempted to observe the effect of phenazine dioxide derivatives on the hepatic xanthine oxidase activity in this study. As the activity of xanthine oxidase, the key enzyme in the generation of superoxide anion radical ($O_2$), was measured in the presence of phenazine dioxide derivatives, the action of 8-acyl-2-hydroxyphenazine-5,10-dioxide derivatives inhibited with increase of numbers of carbon atom bearing 8-acyl group. Moreover, when plotted on double reciprocal form, the Vmax value decrease as increase of numbers of carbon atom bearing acyl groups without affecting the Km value. However, the hepatic xanthine oxidase activity was not changed by 8-acyl-2-aminophenazine-5,10-dioxide derivatives.

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버섯 및 다시마 추출물과 갓의 첨가가 김치의 항산화 특성에 미치는 영향 (Effect of Addition of Mushroom and Sea Tangle Extracts and Mustard Leaf on Anti-oxidant Properties of Kimchi)

  • 하선혜;강순아
    • 한국식품영양학회지
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    • 제31권4호
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    • pp.471-477
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    • 2018
  • The antioxidant properties of mushroom and sea tangle extracts and mustard leaf added to Kimchi were investigated by total phenolic content, DPPH radical scavenging, ABTS anion scavenging, FRAP reducing power, and ORAC value. Total phenolic content of functional Kimchi (FK) was significantly higher than that of control Kimchi (CK). DPPH radical and ABTS anion scavenging activities of functional Kimchi were significantly higher than those of control Kimchi by 2.7 and 1.7 fold, respectively (p<0.05). Also, the FRAP reducing power and ORAC value of functional Kimchi increased compared to those of the control Kimchi by 1.6 and 1.1 fold, respectively (p<0.05). Our results suggest that functional Kimchi made by mushroom and sea tangle extracts and mustard leaf may be a potent antioxidant source and could be developed as a antioxidant functional food that may be for the effective treatment of oxidant conditions. Through continuous research and development of functional Kimchi by the use of mushroom and sea tangle extracts, it will be necessary to try to identify other functions that could be useful for preventing various diseases.

(${\alpha}-Phenyl-N-iso-propylnitrone$유도체에 대한 Sodium Thiophenoxide의 친핵성 첨가반응 메카니즘과 그의 반응 속도론적 연구 (Kinetics and Mechanism of Nucleophilic Addition of Sodium Thiophenoxide to ${\alpha}-Phenyl-N-iso-Propylnitrone$ derivatives)

  • 이광일;김영주;곽천근;장병만;이기창
    • 한국응용과학기술학회지
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    • 제12권2호
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    • pp.93-98
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    • 1995
  • The rate constant of Nucleophilic addition of sodium thiophenoxide to nitrone were determined by UV Spectrophotometry and a rate equation which can be applied over wide pH range was obtained. Base on the rate equation, general base effect, substituent effect and final product, plausible mechanism of addition reaction have been proposed. Blow pH 3.0, the reaction was initiated of thiophenol, and in the range of pH $3.0{\sim}10.0$, proceeded by the competitive addition of thiophenol and thiophenoxide anion. Above the pH 10.0, the reaction proceeded through the addition of a thiophenoxide anion.

DETERMINATION OF THE 129I IN PRIMARY COOLANT OF PWR

  • Choi, Ke Chon;Park, Yong Joon;Song, Kyuseok
    • Nuclear Engineering and Technology
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    • 제45권1호
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    • pp.61-66
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    • 2013
  • Among the radioactive wastes generated from the nuclear power plant, a radioactive nuclide such as $^{129}I$ is classified as a difficult-to-measure (DTM) nuclide, owing to its low specific activity. Therefore, the establishment of an analytical procedure, including a chemical separation for $^{129}I$ as a representative DTM, becomes essential. In this report, the adsorption and recovery rate were measured by adding $^{125}I$ as a radio-isotopic tracer ($t_{1/2}$ = 60.14 d) to the simulation sample, in order to measure the activity concentration of $^{129}I$ in a pressurized-water reactor primary coolant. The optimum condition for the maximum recovery yield of iodine on the anion exchange resins (AG1 x2, 50-100 mesh, $Cl^-$ form) was found to be at pH 7. In this report, the effect of the boron content in a pressurized-water reactor primary coolant on the separation process of $^{129}I$ was examined, as was the effect of $^3H$ on the measurement of the activity of iodine. As a result, no influence of the boron content and of the simultaneous $^3H$ presence was found with activity concentrations of $^3H$ lower than 50 Bq/mL, and with a boron concentration of less than 2,000 ${\mu}g/mL$.

A Chromo- and Fluoroionophoric Thiaoxaaza-Macrocycle Functionalized with Nitrobenzofurazan Exhibiting Mercury(II) Selectivity

  • Lee, Ji-Eun;Lee, Shim-Sung;Choi, Kyu-Seong
    • Bulletin of the Korean Chemical Society
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    • 제31권12호
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    • pp.3707-3710
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    • 2010
  • A chromo/fluorogenic $NO_2S_2$-macrocycle L functionalized with nitrobenzofurazan unit as a dual-signaling probe was synthesized and structurally characterized by single crystal X-ray analysis. In a cation-induced color change experiment, L exhibited excellent $Hg^{2+}$ ion selectivity by showing the color change from orange-red to yellow. However, this hypochromic shift by $Hg^{2+}$ was observed for the weaker coordinating anion system such as ${NO_3}^-$ and ${ClO_4}^-$ ions. The observed anion effect is due to the strong coordination of anions inhibits the bond formation between $Hg^{2+}$ and the macrocyclic tert-N atom, which is sensitive to induce the color change. In the fluorometric experiment, L showed chelate-enhanced fluorescence change effect only with $Hg^{2+}$ ion, together with a change from yellow to green emission. The sensing ability for $Hg^{2+}$ with the proposed chemosensor L is due to the stable complexation with 1:1 stoichiometry (metal-to-ligand).

인돌유도체 I, 1-Benzylindole-3-acetophenone유도체에 대한 Thiourea의 친핵성 첨가반응 메카니즘과 그 반응속도론적 연구 (Indole Derivatives I, The Kinetics and Mechanism of the Nucleopilic Addition of Thiourea to 1-Benzylindole-3-Acetophenone)

  • 이기창;황성규;류정욱;황용현;성기천
    • 한국응용과학기술학회지
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    • 제8권2호
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    • pp.175-181
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    • 1991
  • The kinetics of the addition of 1-benzylindole-3-(p-substituted) acetophenone derivatives was investigated by ultraviolet spectrophotometery in 30% dioxane -$H_2O\;at\;25^{\circ}C$. A rate equation which can be applied over wide pH range was obtained. The Substituent effects on 1-benzylindole-3-(p-substituted) acetophenone derivatives were studied, and addition were facilitated by electron attracting groups. On the base of the rate equation, substituent effect, and general base effect the plausible addition mechanism was proposed : Below pH 3.0, only neutral thiourea molecule was added to the carbon-carbon double bond, and in the range of pH 0.0${\sim}$14.0, netural thiourea molecule and thiourea anion competitively attacted the double bond. By contrast, above pH 10.0, the reaction was dependent upon only the addition of thiourea anion.

Novel Counter Ion Effect on the Disruption of the Homobimetallic Anion,$ (\eta^5-MeCp)Mn(CO)_2Mn(CO)_5-M^+ (M^+=Na^+, PPN^{+a}) by PR_3 (R=C_6H_5,\; C_2H_5,\; OCH_3)$

  • 박용광;김선중;이창환
    • Bulletin of the Korean Chemical Society
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    • 제19권4호
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    • pp.462-466
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    • 1998
  • The homobimetallic anion, $({\eta}^5-MeCp)Mn(CO)_2Mn(CO)_5-M^+\; (M^+=Na^+, PPN^+$) was disrupted by $PR_3\;(R=C_6H_5,\;C_2H_5,\;OCH_3)$ in THF at various temperatures (r.t. ∼65℃) under the pseudo first order reaction conditions where excess of $PR_3$ was employed under a nitrogen atmosphere. For the reaction involving $PPN^+$ analog, Mn-Mn heterolytic cleavage occurred, leading to $PPN^+Mn(CO)_5^-\; and \;({\eta}^5-MeCp)Mn(CO)_2PR_3$ as products; however, in case of $Na^+\; analog,\; Na^+$ seems to play a novel counter ion effect on the disruption reaction by transferring one terminal CO from the $Mn(CO)_5$ moiety on to the $({\eta}^5-MeCp)Mn(CO)_2$ of the corresponding homobimetallic complex, eventually resulting in $Na^+Mn(CO)_4PR_3^-\;and\;({\eta}^5-MeCp)Mn(CO)_3$. This reaction is of overall first order with respect to [homobimetallic complex] with the activation parameters (ΔH≠=23.0±0.7 kcal/mol, ΔS≠= - 8.7±0.8 e.u. for $Na^+$ analog; ΔH≠=28.8±0.4 kcal/mol, ΔS≠=15.7±0.6 e.u. for $PPN^+$ analog reaction).