• Title/Summary/Keyword: methanol activation

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Effects of Shikonin Pigments from the Roots of Lithospermum eryhrorhizon on Rabbit Platelets (자근으로부터 혈소판에 작용하는 천연색소물질에 관한 연구)

  • 박영현;장성근
    • Journal of Food Hygiene and Safety
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    • v.15 no.2
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    • pp.167-172
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    • 2000
  • Lithospermum erythrorhyzon has been used as a red fooddye and traditional Chinese medicine to treat wounds, skin diseases and burns. Platelet activation plays an important role in thrombosis and haemostasis. Here, we studied the inhibition of platelet activation and its active compound from the root of Lithospermum erythrorhyzon. Its ethyl acetate extract inhibited the aggregation of washed rabbit platelets induced by collagen or thrombin. Five naphthoquinone pigments , shikonin , acetylshikonin , is obutylshikonin, $\alpha$-methyl-n-butylshikonin and $\beta$,$\beta$-dimethylacrylshikonin were isolated by means of high pressure liquid chromatography. The structures were determined by comparison of their proton nuclear magnetic resonance spectra. The potency of their inhibition was in the following order : $\beta$,$\beta$-dimethylacrylshikonin$\geq$$\alpha$-methyl-n-butylshikonin>isobutylshikonin>acetylshikonin>shikonin. It is suggested that the size of the aliphatic hydroxy group of shikonin is important for the enhancement of potency.

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Kinetic Studies of the Solvolyses of 4-Nitrophenyl Phenyl Thiophosphorochloridate

  • Koh, Han-Joong;Kang, Suk-Jin
    • Bulletin of the Korean Chemical Society
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    • v.30 no.10
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    • pp.2413-2418
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    • 2009
  • Rates of solvolyses of 4-nitrophenyl phenyl thiophosphorochloridate (4-N$O_2$PhOP(S)(Cl)OPh, $\underline{1}$) in ethanol, methanol, and aqueous binary mixtures incorporating ethanol, methanol, acetone, and 2,2,2-trifluroethanol (TFE) are reported. Thermodynamic parameters were determined at several temperatures in three representative solvents. The extended Grunwald-Winstein equation was applied to 29 solvents and the correlation coefficient (R) showed 0.959. The sensitivities (l = 1.37 and m = 0.62) are similar to those obtained for diphenyl thiophosphorochloridate (($PhO)_2$PSCl, $\underline{2}$), diphenyl phosphorochloridate (($PhO)_2$POCl, $\underline{3}$), diphenyl phosphinic chloride ($Ph_2$POCl, $\underline{4}$), and diphenyl thiophosphinic chloride ($Ph_2$PSCl, $\underline{5}$). The solvolytic reaction mechanism of 4-nitrophenyl phenyl thiophosphorochloridate ($\underline{1}$) is suggested to be proceeded a $S_N$2 process as previously reported result. The activation enthalpies are shown as slightly low as ${\Delta}H^{\neq}\;=\;9.62\;to\;11.9\;kcal{\cdot}mol^{-1}$ and the activation entropies are shown as slightly high negative value as ${\Delta}S^{\neq}\;=\;-34.1\;to\;-44.9\;cal{\cdot}mol^{-1}{\cdot}K^{-1}$ compared to the expected $S_N$2 reaction mechanism. Kinetic solvent isotope effects are accord with a typical $S_N$2 mechanism as shown in the range of 2.41 in MeOH/ MeOD and 2.57 in $H_2O/D_2O$ solvent mixtures.

Kinetics Studies on Nucleophilic Reactions of Methanesulfonyl Chloride with Substituted Aniline in Methanol (메탄올 속에서 치환아닐린과 염화메탄술포닐의 친핵성반응의 속도론적 연구)

  • Lee Suk-Kee
    • Journal of the Korean Chemical Society
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    • v.19 no.3
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    • pp.156-162
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    • 1975
  • Rates of reactions of methanesulfonyl chloride with various substituted anilines have been measured in methanol. Substituent effects in aniline are found to be linearly correlated with pKa(Bronsted relation with ${\beta}$ = 0.84) and ${\rho}$(Hammett equation with ${\rho}$ = -2.46) respectively. The results are interpreted in terms of degree of bond-formation at the transition state, which was found to have progressed relatively further. The rates for o-methylaniline deviated from the Bronsted plot established by meta and para substituted anilines because of a steric effect of ortho position in aniline. Activation parameters, ${\Delta}H^{\neq}$ and ${\Delta}S^{\neq}$ have also been determined. The enthalpy of activation showed a regular variation in that electron donating substituents in the p-substituted aniline decrease ${\Delta}H^{\neq}$ and increase the negative value of ${\Delta}S^{\neq}$.

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Effects of Gentiana scabra var. buergeri Extract on Toxoplasmastic Activity of Macrophages

  • Kang, Sung-Gu;Ryang, Yong-Suk;Kim, In-Sik
    • Biomedical Science Letters
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    • v.9 no.2
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    • pp.85-91
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    • 2003
  • Gentiana scabra var. buergeri (G. scabra) is a herb known to have therapeutic effect in infection diseases. We studied cellular activation and antitoxoplasmosis in macrophages after G. scabra stimulation. Macrophage activation was detected by nitrite production. Macrophages were treated with G. scabra extracted with water or methanol. Maximal nitrite production was detected in macrophages after stimulation of G. scabra extract 0.1 mg/ml. Maximal nitrite concentration was 23.22 0.003 uM/L in macrophages after water extract of G. scabra and was 24.07 1.41 uM/L after methanol extract of G. scabra. Effect of G. scabra in the phagocytic capacity of macrophages was monitored by using PI (percentage of macrophage infected by T gondii) method. The minimum PI (42.5 2.31) was detected in macrophages treated by water extract of G. scabra 0.1 mg/ml before infection of T gondii. We also examined toxoplasmastatic capacity of macrophage using FI (fold increase) method. The minimum FI (4.46 1.16) was shown in macrophages after water extract of G. scabra 0.1 mg/ml pretreatment before infection. Under electron microscope, proliferation of T gondii was inhibited by extract of G. scabra treatment in macrophages and the mitochondrion and lysosomal vacuoles within cells were increased. Taken together, G. scabra extract activates macrophages and induces toxopalsmastatic activity after T gondii infection. It is suggested that G. scabra may be used as a therapeutic drug against toxoplasmosis.

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Immunological Activity and Immunotoxicity of Pine Tree Pollen in Mice (마우스를 이용한 송화분 섭취의 면역원성 및 안전성 탐색)

  • Kim, Young-Ok;Kim, Kwang-Ho;Park, Hyun-Ji;Park, Yeong-Chul;Park, Sung-Wook;Heo, Yong
    • Toxicological Research
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    • v.21 no.3
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    • pp.235-240
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    • 2005
  • Pollen has been used for prevention or treatment of certain diseases such as diabetes arthritis or cancer in traditional medicine. Among various pollens, pine tree pollen is known to relieve hypertension, suppress fatty liver progression, and facilitate the digestion, but its immunological activities are less known. To evaluate immunological reactivities and immunotoxicities of pine tree pollen, BALB/c mice were administered to the poller through oral route. Pine tree pollen suspended in distilled water or extracted with methanol has been administered at the concentration of 0, 10, or 100 mg/kg five days per week for four weeks. Polyclonal activation of splenic T cells with phytohemagglutinins did not induce a significant difference in IL-4 and $IFN_{\gamma}$ production between the pollen-administered mice groups and the control mice. Furthermore, polyclonal activation of splenic B cells with lipopolysaccharides did not result a significant difference in IgG1 and IgG2a production among the groups. These findings imply that the intake of pine tree pollen does not bring any humoral and cellular immune-dysrequlation. Whereas, viability of Listeria monocytogenes was suppressed in the mice administered with 100 mg/kg bw methanol extract, indicating the potential ability of pine tree pollen to enhance cell-mediated immunity mediated by type-1 helper T cells. In addition, aberrant upregulation of plasma IgG1 level was observed in the pollen-administered mice, which suggests a possibility of allergic response induction through the pine tree pollen uptake. Overall, pine tree pollen-mediated modulation of humoral or cellular immunity is worthy of further systematic investigation.

Activating needle coke to develop anode catalyst for direct methanol fuel cell

  • Park, Young Hun;Im, Ui-Su;Lee, Byung-Rok;Peck, Dong-Hyun;Kim, Sang-Kyung;Rhee, Young Woo;Jung, Doo-Hwan
    • Carbon letters
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    • v.20
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    • pp.47-52
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    • 2016
  • Physical and electrochemical qualities were analyzed after KOH activation of a direct methanol fuel cell using needle coke as anode supporter. The results of research on support loaded with platinum-ruthenium suggest that an activated KOH needle coke container has the lowest onset potential and the highest degree of catalyst activity among all commercial catalysts. Through an analysis of the CO stripping voltammetry, we found that KOH activated catalysis showed a 21% higher electrochemical active surface area (ECSA), with a value of 31.37 m2 /g, than the ECSA of deactivated catalyst (25.82 m2 /g). The latter figure was 15% higher than the value of one specific commercial catalyst (TEC86E86).

Antioxidant and Anti-inflammatory Activities of Broccoli Florets in LPS-stimulated RAW 264.7 Cells

  • Hwang, Joon-Ho;Lim, Sang-Bin
    • Preventive Nutrition and Food Science
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    • v.19 no.2
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    • pp.89-97
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    • 2014
  • Broccoli (Brassica oleracea var. italia) florets were extracted with 80% methanol and the extract was sequentially fractionated with n-hexane, ethyl acetate, n-butanol, and distilled water. The extract and the fractions were evaluated for total phenolic content, sulforaphane content, antioxidant activity, and anti-inflammatory activity in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. The total phenolic content and sulforaphane content of the ethyl acetate fraction (EF) were 35.5 mg gallic acid equivalents/g and $620.2{\mu}g/g$, respectively. These values were higher than those of the 80% methanol extract and organic solvent fractions. The oxygen radical absorbance capacity of the EF [$1,588.7{\mu}M$ Trolox equivalents (TE)/mg] was 11-fold higher than that of the distilled water fraction ($143.7{\mu}M\;TE/mg$). The EF inhibited nitric oxide release from LPS-stimulated RAW 264.7 cells in a dose-dependent manner and inhibited $I{\kappa}B-{\alpha}$ degradation and nuclear factor-${\kappa}B$ activation in LPS-stimulated RAW 264.7 cells. In conclusion, the EF of broccoli florets exerted potent antioxidant and anti-inflammatory effects.

Anti-inflammatory Effect of MeOH Extracts of the Stem of Polygonum multiflorum in LPS-stimulated Mouse Peritoneal Macrophages

  • Cha, Dong-Seok;Jeon, Hoon
    • Natural Product Sciences
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    • v.15 no.2
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    • pp.83-89
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    • 2009
  • Polygoni multiflori Ramulus (PM), the stem of Polygonum multiflorum Thunb. has been widely used as a traditional medicine for the treatment of lots of diseases. In macrophages, nitric oxide is released as an inflammatory mediator and has been proposed to be an important modulator of many pathophysiological conditions in inflammation. In the present study, it was investigated that the inhibitory effects on NO and proinflammatory cytokines such as tumor necrosis factor alpha (TNF-${\alpha}$), interleukin-6 (IL-6) and the mechanism of down-regulation of immune response by 85% methanol extracts of PM in mouse (C57BL/6) peritoneal macrophages. Extracts of PM (0.1, 1 mg/ml) suppressed NO production and showed inhibition of proinflammatory cytokines like TNF-${\alpha}$, IL-6 and it attenuated iNOS and COX-2 expression via down-regulation of NF-${\kappa}$B activation. The present results indicate that the 85% methanol extracts of PM has an inhibitory effect on the production of NO through down-regulation of iNOS expression in LPS stimulated mouse peritoneal macrophages and therefore may be beneficial in diseases which related to macrophage-mediated inflammatory disorders.

In vitro Screening of Seaweed Extract on the Proliferation of Mouse Spleen and Thymus Cell

  • Seo, Young-Wan;Kang, Sung-Ho;Lee, Hee-Jung;Kim, You-Ah;Youn, Hyun-Joo;Lee, Burm-Jong;Chung, Ho-Sung
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.11 no.2
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    • pp.160-163
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    • 2006
  • A total number of 31 types of seaweed were assessed with regard to their effects on the proliferation of mouse spleen and thymus cells in a culture, using an MTT reduction assay. Acetone:dichloromethane (1:1) extracts of three seaweed plants: Derbesia marina, Sargassum sp., and Hisikia fuziformis, exhibited significantly positive effects on the survival of mouse spleen and thymus cells in vitro. The acetone:dichloromethane (1:1) extracts of Sargassum sp., in particular, much more potent effects on thymus cell activation than did any of the other types of seaweed. However, the methanol extracts of Sargassum ringgoldianium and Chondrus crispus exerted a stimulatory influence only on the proliferation of mouse spleen cells, whereas the methanol extracts of Grateloupia lanceolata exhibited significant cell proliferation properties in both spleen and thymus cells.

Kinetics of the KOH Catalyzed-Methanolysis for Biodiesel Production from Fat of Tra Catfish

  • Huong, Le Thi Thanh;Tan, Phan Minh;Hoa, Tran Thi Viet;Lee, Soo
    • Journal of the Korean Applied Science and Technology
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    • v.25 no.4
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    • pp.418-428
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    • 2008
  • Transesterification of fat of Tra catfish with methanol in the presence of the KOH catalyst yields fatty acid methyl esters (FAME) and glycerol (GL). The effects of the reaction temperature and reaction time on rate constants and kinetic order were investigated. Three regions were observed. In the initial stage, the immiscibility of the Tra fat and methanol limited the reaction rate, hence this region was controlled by the mass transfer. Subsequent to this region, produced FAME like a co-solvent made the reaction mixture homogeneous, therefore the conversion rate increased rapidly so it was controlled by the kinetic parameters of the reaction until the equilibrium was approached in the final slow region. A second-order kinetic mechanism was proposed involving second regions for the forward reaction. The rate determining step for the overall KOH catalyzed-methanolysis of Tra fat was the conversion of triglycerides (TG) to diglycerides (DG). This rate constant was increased from 0.003 to $0.019min^{-1}$ when the reaction temperature was increased from 35 to $60^{\circ}C$. Its calculated activation energy was 14.379 ($kcal.mol^{-1}$).