• Title/Summary/Keyword: methanol activation

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Inhibitory Effect of Rosmarinic acid Extrcted from Euonymus Alatus on Cyclooxygenase-2

  • Ryu, Jung-Man
    • The Journal of Korean Medicine
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    • v.29 no.5
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    • pp.111-117
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    • 2008
  • Objectives and methods : Previous mechanistic studies suggest the cyclooxygenase-2 (COX-2) inhibitors represent the good candidates against tumor progression. MeOH extract of the stem barks of Euonymus alatus induced the strong inhibition of COX-2. A phenolic compound responsible for the anti- COX-2 known to involve in tumor adhesion and invasion has been studied through the methanol extracts. The compound, rosmarinic acid (ROS-A) was an ester of caffeic acid and 3,4-dihydroxyphenyllactic acid. ROS-A showed a strong inhibitory effect of COX-2 activity in a concentration-dependent manner. Then we have measured the IL-1${\beta}$, IL-6 and TNF-${\alpha}$ production related the immune regulation, induction of inflammatory related genes. Results and Conclusions :Hep3B cells produce proinflammatory cytokines of IL-1${\beta}$, IL-6 and TNF-${\alpha}$ while ROS A inhibited the cytokines production. Since IL-1${\beta}$, IL-6 and TNF-${\alpha}$ need the transcription factors such as nuclear factor- ${\kappa}$B (NF-${\kappa}$B) and activated protein-1 (AP-1), we measured the transcription factors. ROS-A inhibited the activation of p65, p50, c-Rel subunits of NF-${\kappa}$B and AP-1 transcription factors. These findings indicate that ROS A from the stem bark of E. alatus inhibits proliferation in metastatic cancer cells. It was suggested that stem barks of E. alatus could be suitable for anti-cancer drugs.

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Kinetics and Mechanistic Chemistry of Oxidation of Butacaine Sulfate by Chloramine-B in Acid Medium

  • Shubha, Jayachamarajapura Pranesh;Kotabagi, Vinutha;Puttaswamy, Puttaswamy
    • Bulletin of the Korean Chemical Society
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    • v.33 no.11
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    • pp.3539-3543
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    • 2012
  • Butacaine sulfate is an ester of p-aminobenzoic acid which has been widely used as a local anaesthetic and it is a long standing agent particularly for spinal anaesthesia. For this reason, a kinetic study of oxidation of butacaine sulfate by sodium N-chlorobenzenesulfonamide (chloramine-B or CAB) has been carried out in $HClO_4$ medium at 303 K in order to explore this redox system mechanistic chemistry. The rate shows a first-order dependence on both $[CAB]_o$, and $[substrate]_o$, and a fractional-order dependence on acid concentration. Decrease of dielectric constant of the medium, by adding methanol, increases the rate of the reaction. Variation of ionic strength and addition of benzenesulfonamide or NaCl have no significant effect on the rate. The reaction was studied at different temperatures and the activation parameters have been evaluated. The stoichiometry of the reaction has been found to be 1:2 and the oxidation products have been identified by spectral analysis. The observed results have been explained by plausible mechanism and the related rate law has been deduced.

Inhibitors of Nitric Oxide Syntheasis from Phellinus pini in Murine Macrophages (낙엽송층버섯의 Nitric Oxide 생성저해 물질)

  • Jang, Hyun-Jin;Kim, Ahn-Keun;Pyo, Myoung-Yun;Yang, Ki-Sook
    • YAKHAK HOEJI
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    • v.51 no.6
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    • pp.430-434
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    • 2007
  • The anti-inflammatory activity of fruit body of Phellinus pini was investigated by activity-guided fractionation. From the screening of each fraction for the inhibitory activity of NO production in lipopolysaccaride (LPS) activated RAW 264.7 cells, methanol extract and its hexane soluble fraction of Phellinus pini exhibited inhibition of NO production compared with LPS control without toxicity. The hexane soluble fraction showed dose-dependent inhibition of NO production. The active hexane fraction was repeatedly chromatographed over silica gel, ergosta-7,24(28)-dien-3-ol(1) and ergosterol peroxide (2) were isolated and identified. Ergosterol derivatives were inhibited NOS activation, $IC_{50}$ of them were $18.9{\pm}3.9{\mu}M$ (1) and $20.4{\pm}4.5{\mu}M$ (2).

Induction of Apoptosis by Extracts of Trichosanthes kirilpwii var. japonica in HL-60 Leukemia Cells (노랑하늘타리 추출물의 HL-60 혈액종양세포 Apoptosis 유도 효과)

  • 김상철;박수영;현재희;이영기;박덕배;강사윤;유은숙;강희경
    • YAKHAK HOEJI
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    • v.47 no.5
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    • pp.319-324
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    • 2003
  • This study examined the inhibitory effect of extracts of Trichosanthes kirilpwii sorted according to the parts on the growth of HL-60 cells. The growth of HL-60 leukemia cells was markedly inhibited by the treatment of the 80% methanol extract of roots (10 $\mu\textrm{g}$/mι), stems (50$\mu\textrm{g}$/mι), pips (10$\mu\textrm{g}$/mι), and gourds (100 $\mu\textrm{g}$/mι), or the ethylacetate fraction of leaves (100 $\mu\textrm{g}$/mι). when the HL-60 cells were treated with the extracts of T. kirilpwii sorted according to the parts, DNA fragmentation and sub-G1 hypodiploid cells were observed. Moreover, T. kirilpwii extracts increased the level of the expression of the active form of caspase-3 and the activation of caspase-3 was demonstrated by the cleavage of poly(ADP-ribose) polymerase, a vital substrate of effector caspase. The results suggest that the inhibitory effect of extracts of T. kirilpwii sorted according to the parts on the growth of HL-60 cells seems to arise from the induction of apoptosis.

Preparation and Characterization of $Pd/CeO_2/Ta/Si$ model catalysts

  • 김도희;우성일
    • Proceedings of the Korean Vacuum Society Conference
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    • 2000.02a
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    • pp.145-145
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    • 2000
  • M-CeO2 (M : noble metal) catalysts have been widely studied as three-way catalysts and methanol synthesis catalysts. Ceria is thought to play a number of roles in these catalysts. The Ce(IV)/Ce(III) redox pair may store/release gases under oxidizing/reducing conditions, extending the operational window. Additionally, metal-ceria interactions lead to several effects, including the dispersion of the active components and promoting the activation of molecules such as CO or NO. Pd is a promising component to current TWC formulations and behaves particularly well when compared with Pt and Rh-based catalysts for low-temperature oxidation of Co and hydrocarbon. However the effect of Pd-ceria interactions on the physicochemical properties of Pd and the redox properties of Ce is not elucidated yet. In order to know exactly about the metal-ceria interactions, the model study are expecting to give a better environment, resulting in the wide use of the surface science tools. The substrate was Si(100) wafer, on which Ta metal was sputtered as a thickness of 100nm. The CeO2 thin film of 30nm was deposited by using the magnetron sputtering. Spin coating and magnetron sputtering methods were used to make the Pd thin film layer. The prepared sample was investigated by in-situ XPS, AES, SEM and AFM analysis.

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Identification of Benzidine Metabolites in Rats by Gas Chromatography/Mass Selective Detector and its Toxicity in vitro (Gas-Chromatography/Mass Selective Detector를 사용하여 쥐의 뇨시료 중 benzidine 대사체의 확인 및 in vitro 독성)

  • 류재천;권오승
    • YAKHAK HOEJI
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    • v.44 no.5
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    • pp.384-390
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    • 2000
  • Metabolism study of the dye, benzidine, was performed by gas chromatography-mass selective detector (GC/MSD) in the urine of rats orally administered 100 mg/kg benzidine. Urine samples were collected in metabolic cages for 0-24, 24-48, and 48-72 hrs. Ten ml of the urine was extracted with XAD-2 resin and the XAD-2 column was eluted with methanol. After evaporation, benzidine and its metabolites were extracted with diethyl ether (for non-conjugated fraction). For conjugated metabolites, $\beta$-glucu-ronidase was added to the aqueous layer that was incubated for 1 hr at 5$0^{\circ}C$ and the aqueous layer was extracted as in non-conjugated fraction. Aliquot of trimethylsilylated derivatives was applied to the GC/MSD. The mutagenicity of benzidine and its acetylated metabolites was tested by histidine/reversion assay. Five metabolites observed and confirmed either by electron impact and chemical ionization modes of the GC/MSD, or authentic compounds were monoacetyl-, diacetyl-, hydroxyacetyl-, hydroxydiacetyl-, and hydroxy-benzidine. Monoacetyl-benzidine was more potent than benzidine in histidine/reversion assay. This data indicates that monoacetylation of benzidine may be one of the metabolites produced in metabolic activation process.

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Anti-inflammatory Effect of Leaves Extracts from Aralia cordata through Inhibition of NF-κB and MAPKs Signaling in LPS-stimulated RAW264.7 Cells

  • Ji, Eo Hyun;Kim, Da Som;Sim, Su Jin;Park, Gwang Hun;Song, Jeong Ho;Jeong, Jin Boo;Kim, Nahyun
    • Korean Journal of Plant Resources
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    • v.31 no.6
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    • pp.634-640
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    • 2018
  • Aralia cordata (A. cordata), which belongs to Araliaceae, is a perennial herb widely distributed in East Asia. We evaluated the anti-inflammatory effect of stems (AC-S), roots (AC-R) and leaves (AC-L) extracted with 100% methanol of A. cordata and elucidated the potential signaling pathway in LPS-stimulated RAW264.7 cells. The AC-L showed a strong anti-inflammatory activity through inhibition of NO production. AC-L dose-dependently inhibited NO production by suppressing iNOS, COX-2 and $IL-{\beta}$ expression in LPS-stimulated RAW264.7 cells. AC-L inhibited the degradation and phosphorylation of $I{\kappa}B-{\alpha}$, which donated to the inhibition of p65 nuclear accumulation and $NF-{\kappa}B$ activation. Furthermore, AC-L suppressed the phosphorylation of ERK1/2 and p38. These results suggested that AC-L may utilize anti-inflammatory activity by blocking $NF-{\kappa}B$ and MAPK signaling pathway and indicated that the AC-L can be used as a natural anti-inflammatory drugs.

Effect of Yong-dam-sa-gan-tang on apoptosis in human hepatoma HepG2 (용담사간탕(龍膽瀉肝湯)에 의해 유도된 MAP kinases 활성화를 통한 간암 세포주 HepG2의 세포사멸)

  • Yun, Hyun-Jeong;Kim, Han-Seong;Heo, Sook-Kyoung;Hwang, Seong-Goo;Park, Won-Hwan;Park, Sun-Dong
    • Herbal Formula Science
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    • v.15 no.2
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    • pp.127-137
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    • 2007
  • The purpose of this study was to investigate the effect of Yong-dam-sa-gan-tang (YST) on apoptosis in HepG2 cells, First of all. to study the cytotoxic effect of methanol extract of YST on HepG2 cells, the cells were treated with various concentrations of YST and then cell viability was determined by XTT reduction method and trypan blue exclusion assay. YST reduced proliferation of HepG2 cells in a dose-dependent manner. To confirm the induction of apoptosis, HepG2 cells were treated with various concentrations of YST. The cleavage of poly AD P-ribose polymerase (P ARP), a substrate for caspase-3 and a typical sign of apoptosis, and the activation of caspase-3, procaspase-8 and procaspase-8 were examined by western blot analysis. YST decreased procaspase-3, procaspase-8 and procaspase-9 levels in a dose-dependent manner and induced the clevage of PARP. YST triggered the mitochondrial apoptotic signaling by increasing the release of cytochrome c from mitochondria to cytosol. Furthermore, YST also downregulated the anti-apoptotic Bcl-2 and upregulated the pro-apoptotic-Bax. Therefore, this result suggest that YST induced HepG2 cell death through the mitochondrial pathway. Sustained activation of the Ras/Raf/MEK/ERK cascade in cells results in a cell cycle arrest and has been implicated in the differentiation of certain cell types, in many cases acting to promote differentiation. YST decreased the activation of Ras/Raf/MEK/ERK cascade in a dose-dependent manner. These results suggest that YST is potentially useful as a chemo-therapeutic agent in HepG2.

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Characterization of Poly(methyl methacrylate)-tin (IV) Chloride Blend by TG-DTG-DTA, IR and Pyrolysis-GC-MS Techniques

  • Arshad, Muhammad;Masud, Khalid;Arif, Muhammad;Rehman, Saeed-Ur;Saeed, Aamer;Zaidi, Jamshed Hussain
    • Bulletin of the Korean Chemical Society
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    • v.32 no.9
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    • pp.3295-3305
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    • 2011
  • Thermal behavior of poly (methyl methacrylate) was analyzed in the presence of tin (IV) chloride. Five different proportions - polymer to additive - were selected for casting films from common solvent. TG, DTG and DTA were employed to monitor thermal degradation of the systems. IR and py-GC-MS helped identify the decomposition products. The blends start degrading at a temperature lower than that of the neat polymer and higher than that of the pure additive. Complex formation between tin of additive and carbonyl oxygen (pendent groups of MMA units) was noticed in the films soon after the mixing of the components in the blends. The samples were also heated at three different temperatures to determine the composition of residues left after the expulsion of volatiles. The polymer, blends and additive exhibited a one step, two-step and three-step degradation, respectively. $T_0$ is highest for the polymer, lowest for the additive and is either $60^{\circ}C$ or $70^{\circ}C$ for the blends. The amount of residue increases down the series [moving from blend-1 (minimum additive concentration) to blend-5 (maximum additive concentration)]. For blend-1, it is 7% of the original mass whereas it is 16% for blend-5. $T_{max}$ also goes up as the concentration of additive in the blends is elevated. The complexation appears to be the cause of observed stabilization. Some new products of degradation were noted apart from those reported earlier. These included methanol, isobutyric acid, acid chloride, etc. Molecular-level mixing of the constituents and "positioning effect" of the additive may have brought about the formation of new compounds. Routes are proposed for the appearance of these substances. Horizontal burning tests were also conducted on polymer and blends and the results are discussed. Activation energies and reaction orders were calculated. Activation energy is highest for the polymer, i.e., 138.9 Kcal/mol while the range for blends is from 51 to 39 Kcal/mol. Stability zones are highlighted for the blends. The interaction between the blended parts seems to be chemical in nature.

Production of a hypothetical polyene substance by activating a cryptic fungal PKS-NRPS hybrid gene in Monascus purpureus (홍국Monascus purpureus에서 진균 PKS-NRPS 하이브리드 유전자의 발현 유도를 통한 미지 polyene 화합물의 생성)

  • Suh, Jae-Won;Balakrishnan, Bijinu;Lim, Yoon Ji;Lee, Doh Won;Choi, Jeong Ju;Park, Si-Hyung;Kwon, Hyung-Jin
    • Journal of Applied Biological Chemistry
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    • v.61 no.1
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    • pp.83-91
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    • 2018
  • Advances in bacterial and fungal genome mining uncover a plethora of cryptic secondary metabolite biosynthetic gene clusters. Guided by the genome information, targeted transcriptional derepression could be employed to determine the product of a cryptic gene cluster and to explore its biological role. Monascus spp. are food grade filamentous fungi popular in eastern Asia and several genome data belong to them are now available. We achieved transcription activation of a cryptic fungal polyketide synthase-nonribosomal peptide synthase gene Mpfus1 in Monascus purpureus ${\Delta}MpPKS5$ by inserting Aspergillus gpdA promoter at the upstream of Mpfus1 through double crossover gene replacement. The gene cluster with Mpfus1 show a high similarity to those for the biosynthesis of conjugated polyene derivatives with 2-pyrrolidone ring and the mycotoxin fusarin is the representative member of this group. The ${\Delta}MpPKS5$ is incapable of producing azaphilone pigment, providing an excellent background to identify chromogenic and UV-absorbing compounds. Activation of Mpfus1 resulted in a yellow hue on mycelia and its methanol extract exhibit a maximum absorption at 365 nm. HPLC analysis of the organic extracts indicated the presence of a variety of yellow compounds in the extract. This implies that the product of MpFus1 is metabolically or chemically unstable. LC-MS analysis guided us to predict the MpFus1 product and to propose that the Mpfus1-containing gene cluster encode the biosynthesis of a desmethyl analogue of fusarin. This study showcases the genome mining in Monascus and the possibility to unveil new biological activities embedded in it.