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1.
Biomol Ther (Seoul) ; 29(2): 220-226, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32952129

RESUMO

The role of particulate matter (PM) in health problems including cardiovascular diseases (CVD) and pneumonia is becoming increasingly clear. Polycyclic aromatic hydrocarbons, major components of PM, bind to aryl hydrocarbon receptor (AhRs) and promote the expression of CYP1A1 through the AhR pathway in keratinocytes. Activation of AhRs in skin cells is associated with cell differentiation in keratinocytes and inflammation, resulting in dermatological lesions. Oleanolic acid, a natural component of L. lucidum, also has anti-inflammation, anticancer, and antioxidant characteristics. Previously, we found that PM10 induced the AhR signaling pathway and autophagy process in keratinocytes. Here, we investigated the effects of oleanolic acid on PM10-induced skin aging. We observed that oleanolic acid inhibits PM10-induced CYP1A1 and decreases the increase of tumor necrosis factor- alpha and interleukin 6 induced by PM10. A supernatant derived from keratinocytes cotreated with oleanolic acid and PM10 inhibited the release of matrix metalloproteinase 1 in dermal fibroblasts. Also, the AhR-mediated autophagy disruption was recovered by oleanolic acid. Thus, oleanolic acid may be a potential treatment for addressing PM10-induced skin aging.

2.
Adv Mater ; 28(42): 9301-9307, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27604816

RESUMO

A novel ionic mixture of an imidazolium-based room-temperature ionic liquid containing ethylene-oxide-functionalized phosphite anions is fabricated, which, when doped with lithium salt, self-assembles into a smectic-ordered ionic liquid crystal through Coulombic interactions between the ion species. Interestingly, the smectic order in the ionic-liquid-crystal ionogel facilitates ionic transport.

3.
Environ Sci Technol ; 48(7): 4163-70, 2014 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-24597716

RESUMO

The pathways for the CO2 absorption and desorption in an aqueous solution of a heavily hindered alkanolamine, 2-(t-butylamino)ethanol (TBAE) were elucidated by X-ray crystallographic and (13)C NMR spectroscopic analysis. In the early stage of the CO2 absorption, the formation of carbonate species ([TBAEH]2CO3) was predominant, along with the generation of small amounts of zwitterionic species. With the progress of the absorption, the carbonate species was rapidly transformed into bicarbonate species ([TBAEH]HCO3), and the amounts of the zwitterionic species increased gradually. During desorption at elevated temperature in the absence of CO2, [TBAEH]HCO3 was found to transform into [TBAEH]2CO3, where CO3(2-) strongly interacts with two [TBAEH](+) via hydrogen bondings.


Assuntos
Aminas/química , Dióxido de Carbono/química , Água/química , Absorção , Cristalografia por Raios X , Etanol/química , Íons , Espectroscopia de Ressonância Magnética , Conformação Molecular , Soluções
4.
J Hazard Mater ; 264: 136-43, 2014 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-24291666

RESUMO

Three different types of nitrile-functionalized amines, including 3-(N,N-diethylamino)propionitrile (DEAPN), 3-(N,N-dibutylamino)propionitrile (DBAPN), and N-methyl-N,N-dipropionitrile amine (MADPN) were synthesized, and their SO2 absorption performances were evaluated and compared with those of hydroxy-functionalized amines such as N,N-diethyl-N-ethanol amine (DEEA), N,N-dibutyl-N-ethanol amine (DBEA), and N-methyl-N,N-diethanol amine (MDEA). Absorption-desorption cycle experiments clearly demonstrate that the nitrile-functionalized amines are more efficient than the hydroxy-functionalized amines in terms of absorption rate and regenerability. Computational calculations with DBEA and DBAPN revealed that DBEA bearing a hydroxyethyl group chemically interacts with SO2 through oxygen atom, forming an ionic compound with a covalently bound OSO2(-) group. On the contrary, DBAPN bearing a nitrile group physically interacts with SO2 through the nitrogen and the hydrogen atoms of the two methylene groups adjacent to the amino and nitrile functionalities.


Assuntos
Aminas/química , Nitrilas/química , Dióxido de Enxofre/isolamento & purificação , Adsorção
5.
ChemSusChem ; 6(5): 890-7, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23576306

RESUMO

Tetramethylammonium-based molten salts bearing a ß-amino acid anion (TMAAs) are synthesized through Michael addition reactions of amines with methyl acrylate followed by hydrolysis and subsequent neutralization by using aqueous tetramethylammonium hydroxide. The CO(2) capture performances of the TMAAs are evaluated and are shown to interact with CO(2) in a 1:1 mode in both water and alcohol. FTIR and (13)C NMR spectroscopic studies on the interactions of TMAAs with CO(2) indicate that the type of CO(2) adduct varies with the solvent used. When water is used as the solvent, a bicarbonate species is produced, whereas hydroxyethylcarbonate and methylcarbonate species are generated in ethylene glycol and methanol, respectively. Computational calculations show that the carboxylate groups of TMAAs contribute towards the formation and stabilization of 1:1 CO(2) adducts through hydrogen bonding interactions with the hydrogen atoms of the amino groups.


Assuntos
Poluentes Atmosféricos/química , Aminoácidos/química , Dióxido de Carbono/química , Compostos de Amônio Quaternário/química , Adsorção , Ânions/química , Carbonatos/química , Ácidos Carboxílicos/química , Espectroscopia de Ressonância Magnética , Espectroscopia de Infravermelho com Transformada de Fourier
6.
Biosci Biotechnol Biochem ; 75(8): 1490-5, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21821946

RESUMO

To improve its bioavailability and pharmacological effects in humans, red ginseng was fermented with a newly isolated fungus, Monascus pilosus KMU103. Most of the ginsenosides were converted to deglycosylated ginsenocides, such as Rh(1), Rh(2), and Rg(3). The total amount of ginsenosides Rh(1), Rh(2), and Rg(3) was 838.7 mg/kg in the red ginseng, and increased to 4,117 mg/kg after 50 L fermentation in 13% red ginseng and 2% glucose. In addition, the Monascus-fermented red ginseng contained 3,089 mg/kg of monacolin K, one of the metabolites produced by Monascus known to reduce cholesterol in the blood. This newly developed Monascus-fermented red ginseng should result in improved health effects, not only by biotransforming gisenosides to deglycosylated ones but also by creating additional bioactive compounds.


Assuntos
Anticolesterolemiantes , Biotecnologia/métodos , Ginsenosídeos , Lovastatina , Monascus/química , Panax/química , Anticolesterolemiantes/química , Anticolesterolemiantes/isolamento & purificação , Anticolesterolemiantes/metabolismo , Reatores Biológicos , Biotransformação , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Fermentação , Ginsenosídeos/química , Ginsenosídeos/isolamento & purificação , Ginsenosídeos/metabolismo , Humanos , Lovastatina/química , Lovastatina/isolamento & purificação , Lovastatina/metabolismo , Extratos Vegetais/química
7.
J Phys Chem B ; 115(5): 1067-74, 2011 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-21218815

RESUMO

Room temperature ionic liquids (RTILs) are proposed as the alternative solvents for the acetylene separation in ethylene generated from the naphtha cracking process. The solubility behavior of acetylene in RTILs was examined using a linear solvation energy relationship based on Kamlet-Taft solvent parameters including the hydrogen-bond acidity or donor ability (α), the hydrogen-bond basicity or acceptor ability (ß), and the polarity/polarizability (π*). It is found that the solubility of acetylene linearly correlates with ß value and is almost independent of α or π*. The solubility of acetylene in RTILs increases with increasing hydrogen-bond acceptor (HBA) ability of the anion, but is little affected by the nature of the cation. Quantum mechanical calculations demonstrate that the acidic proton of acetylene specifically forms hydrogen bond with a basic oxygen atom on the anion of a RTIL. On the other hand, although C-H···π interaction is plausible, all optimized structures indicate that the acidic protons on the cation do not specifically associate with the π cloud of acetylene. Thermodynamic analysis agrees well with the proposed correlation: the higher the ß value of a RTIL is, the more negative the enthalpy of acetylene absorption in the RTIL is.

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