Página 1 dos resultados de 30 itens digitais encontrados em 0.008 segundos

Iron chelating-mediated antioxidant activity of Plectranthus barbatus extract on mitochondria

MAIOLI, Marcos A.; ALVES, Larissa C.; CAMPANINI, Andre L.; LIMA, Michele C.; DORTA, Daniel J.; GROPPO, Milton; CAVALHEIRO, Alberto J.; CURTI, Carlos; MINGATTO, Fabio E.
Fonte: ELSEVIER SCI LTD Publicador: ELSEVIER SCI LTD
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
36.01%
Plectranthus barbatus Andrews (Lamiaceae) is a popular medicinal plant used to treat gastrointestinal and hepatic ailments. In this work, we assessed the antioxidant activity of the aqueous extract of P. barbatus leaves on Fe(2+)-citrate-mediated membrane lipid peroxidation in isolated rat liver mitochondria, as well in non-mitochondrial systems: DPPH reduction, (center dot)OH scavenging activity, and iron chelation by prevention of formation of the Fe(2+)-bathophenanthroline disulfonic acid (BPS) complex. Within all the tested concentrations (15-75 mu g/ml), P. barbatus extract presented significant free radical-scavenging activity (IC(50) = 35.8 +/- 0.27 mu g/ml in the DPPH: assay and IC(50) = 69.1 +/- 0.73 mu g/ml in the (center dot)OH assay) and chelated iron (IC(50) = 30.4 +/- 3.31 mu g/ml). Over the same concentration range, the plant extract protected mitochondria against Fe(2+)/citrate-mediated swelling and malondialdehyde production, a property that persisted even after simulation of its passage through the digestive tract. These effects could be attributed to the phenolic compounds, nepetoidin - caffeic acid esters, present in the extract. Therefore, P. barbatus extract prevents mitochondrial membrane lipid peroxidation, probably by chelation of iron...

Iron chelating-mediated antioxidant activity of Plectranthus barbatus extract on mitochondria

Maioli, Marcos A.; Alves, Larissa C.; Campanini, Andre L.; Lima, Michele C.; Dorta, Daniel J.; Groppo, Milton; Cavalheiro, Alberto José; Curti, Carlos; Mingatto, Fábio Erminio
Fonte: Elsevier B.V. Publicador: Elsevier B.V.
Tipo: Artigo de Revista Científica Formato: 203-208
ENG
Relevância na Pesquisa
36.01%
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Plectranthus barbatus Andrews (Lamiaceae) is a popular medicinal plant used to treat gastrointestinal and hepatic ailments. In this work, we assessed the antioxidant activity of the aqueous extract of P. barbatus leaves on Fe(2+)-citrate-mediated membrane lipid peroxidation in isolated rat liver mitochondria, as well in non-mitochondrial systems: DPPH reduction, (center dot)OH scavenging activity, and iron chelation by prevention of formation of the Fe(2+)-bathophenanthroline disulfonic acid (BPS) complex. Within all the tested concentrations (15-75 mu g/ml), P. barbatus extract presented significant free radical-scavenging activity (IC(50) = 35.8 +/- 0.27 mu g/ml in the DPPH: assay and IC(50) = 69.1 +/- 0.73 mu g/ml in the (center dot)OH assay) and chelated iron (IC(50) = 30.4 +/- 3.31 mu g/ml). Over the same concentration range, the plant extract protected mitochondria against Fe(2+)/citrate-mediated swelling and malondialdehyde production, a property that persisted even after simulation of its passage through the digestive tract. These effects could be attributed to the phenolic compounds, nepetoidin - caffeic acid esters...

CAFFEIC ACID-ESTERS AND TRITERPENES OF ALIBERTIA-MACROPHYLLA

Bolzani, Vanderlan da Silva; Trevisan, LMV; Young, MCM
Fonte: Elsevier B.V. Publicador: Elsevier B.V.
Tipo: Artigo de Revista Científica Formato: 2089-2091
ENG
Relevância na Pesquisa
86.56%
A hydroalcoholic extract of the leaves of Alibertia macrophylla afforded the esters of caffeic acid and 2-phenylethanol or 2-methyl butane-1,4-diol. The leaves also contain caffeic acid. The acetone extract of the stems of A. macrophylla contain alpha-amyrin, beta-amyrin, alpha-amyrenone, beta-amyrenone, lupeol, lupenone and germanicone. Structural assignments were taken through spectral data analysis and physical properties. This is the first report on the chemistry of Alibertia.

Caffeic acid esters and triterpenes of Alibertia macrophylla

Bolzani, Vanderlan da Silva; Trevisan, Lígia M.V.; Young, M.Claudia M.
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 2089-2091
ENG
Relevância na Pesquisa
86.56%
A hydroalcoholic extract of the leaves of Alibertia macrophylla afforded the esters of caffeic acid and 2-phenylethanol or 2-methyl butane-1,4-diol. The leaves also contain caffeic acid. The acetone extract of the stems of A. macrophylla contain α-amyrin, β-amyrin, α-amyrenone, β-amyrenone, lupeol, lupenone and germanicone. Structural assignments were taken through spectral data analysis and physical properties. This is the first report on the chemistry of Alibertia. © 1991.

Ácido cafeico e seus ésteres: inibição do burst oxidativo de neutrófilos e efeito anti-Helicobacter pylori

Paracatu, Luana Chiquetto
Fonte: Universidade Estadual Paulista (UNESP) Publicador: Universidade Estadual Paulista (UNESP)
Tipo: Dissertação de Mestrado Formato: 83 f. : il., gráfs., tabs.
POR
Relevância na Pesquisa
36.83%
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Pós-graduação em Biociências e Biotecnologia Aplicadas à Farmácia - FCFAR; A ação patogênica do Helicobacter pylori envolve a colonização do trato gastrointestinal e a produção de EROs por neutrófilos atraídos e ativados pelo agente da infecção. A reação mediada pelos PMN é, todavia, ineficaz para eliminar o H. pylori e as EROs contribuem para a lesão tecidual e desenvolvimento de gastrites e úlcera péptica. O ácido cafeico é um dos mais importantes compostos fenólicos, e apresenta diferentes propriedades biológicas, entre elas antioxidante e antimicrobiana. O objetivo deste estudo foi avaliar a atividade antioxidante e anti-H.pylori do ácido cafeico e seus ésteres. Foram avaliados os ésteres: cafelato de metila, cafelato de butila e cafelato de heptila e realizada uma comparação entre as propriedades antioxidantes do ácido cafeico e tais ésteres, por meio de ensaio de quimiluminescência dependente de luminol e lucigenina, ensaio de inibição da produção do ácido hipocloroso e também ensaios morfológicos com e sem a presença de NBT. Os resultados deste estudo mostraram que os ésteres do ácido cafeico apresentaram melhores resultados em comparação com o ácido cafeico para a capacidade antioxidante. O cafelato de heptila apresentou os melhores resultados para a quimiluminescência dependente de luminol e lucigenina induzida por H. pylori e/ou zymozan opsonizado na concentração de 10 µM e 1 µM . O efeito do ácido cafeico e seus ésteres...

Alkyl Caffeates as Anti-Helicobacter Pylori and Scavenger of Oxidants Produced by Neutrophils

Paracatu, Luana Chiquetto; Bonacorsi, Cibele; Quinello Gomes de Farias, Carolina Maria; Nazare, Ana Carolina; Petronio, Maicon Segalla; Regasini, Luiz Octavio; Siqueira Silva, Dulce Helena; Goncalves Raddi, Maria Stella; Fonseca, Luiz Marcos da; Ximenes,
Fonte: Bentham Science Publ Ltd Publicador: Bentham Science Publ Ltd
Tipo: Artigo de Revista Científica Formato: 74-80
ENG
Relevância na Pesquisa
46.59%
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Helicobacter pylori pathogenic action involves the colonization of the gastrointestinal tract and a large production of reactive oxygen species (ROS) by the neutrophils attracted to the site of infection. The aim of this study was to evaluate caffeic acid and its alkyl esters as inhibitors of the release of ROS by Helicobacter pylori activated neutrophils and their bactericidal effect. The increased hydrophobicity caused by esterification had direct consequence in their efficiency as bactericidal agents against H. pylori and inhibitors of the production of ROS by neutrophils. The minimum inhibitory concentration (MIC) decreased from higher than 1000 mu g/mL (caffeic acid) to 250 mu g/mL to butyl and heptyl caffeate. The release of total ROS, superoxide anion and hypochlorous acid by activated neutrophils was also significantly decreased and the esters were more efficient than the acid precursor. In conclusion, the alkyl esters of caffeic acid have two properties that are complementary for the treatment of H. pylori infections: bactericidal activity and inhibitory effect upon generation of ROS by neutrophils. Hence...

Quality improvement of a white and a red wine with less sulphur dioxide by the addition of a mixture of glutathione, caffeic acid and gallic acid

Roussis, I. G.; Oliveira, J. M.; Patrianakou, M.; Cerdeira, A. L.; Drossiadis, A.
Fonte: Universidade do Minho Publicador: Universidade do Minho
Tipo: Conferência ou Objeto de Conferência
Publicado em //2012 ENG
Relevância na Pesquisa
66.33%
The effect of a mixture of glutathione, caffeic acid and gallic acid, at 20 mg/L, 60 mg/L and 20 mg/L respectively, on the quality of a white and a red wine with less than the typical SO2 was studied. The mixture was added in Vinho Verde white wine containing 20 mg/L free SO2 at bottling. Wine quality was evaluated in comparison with wine with 20 mg/L and control wine with typical (35 mg/L) free SO2. By the storage time, wine in which the mixture was added appeared to be of better quality than that with 20 mg/L free SO2. It exhibited higher scores in sensory attributes and lower degree of oxidation as indicated by the chromatic characteristics L*, b* and C*. Wine with typical SO2 exhibited higher scores in sensory analysis than the others. The same mixture was also added into a Merlot-Cabernet Sauvignon blend red wine at bottling. Wine quality was evaluated during storage in comparison with wine with 25 mg/L and control wine with typical (35 mg/L) free SO2. By the storage time, wine in which the mixture was added appeared to be of better sensory quality than that with 25 mg/L free SO2. Moreover, it exhibited higher concentrations of some aroma esters compared to wine with less SO2, similar to those of wine with typical SO2, as determined by SPME/GC-MS analysis. Wine with typical SO2 exhibited better aroma than the others.

Developmental Expression and Substrate Specificities of Alfalfa Caffeic Acid 3-O-Methyltransferase and Caffeoyl Coenzyme A 3-O-Methyltransferase in Relation to Lignification1

Inoue, Kentaro; Sewalt, Vincent J.H.; Murray Ballance, G.; Ni, Weiting; Stürzer, Cornelia; Dixon, Richard A.
Fonte: American Society of Plant Physiologists Publicador: American Society of Plant Physiologists
Tipo: Artigo de Revista Científica
Publicado em /07/1998 EN
Relevância na Pesquisa
46.32%
The biosynthesis of monolignols can potentially occur via two parallel pathways involving free acids or their coenzyme A (CoA) esters. Caffeic acid 3-O-methyltransferase (COMT) and caffeoyl CoA 3-O-methyltransferase (CCOMT) catalyze functionally identical reactions in these two pathways, resulting in the formation of mono- or dimethoxylated lignin precursors. The activities of the two enzymes increase from the first to the sixth internode in stems of alfalfa (Medicago sativa L.), preceding the deposition of lignin. Alfalfa CCOMT is highly similar at the amino acid sequence level to the CCOMT from parsley, although it contains a six-amino acid insertion near the N terminus. Transcripts encoding both COMT and CCOMT are primarily localized to vascular tissue in alfalfa stems. Alfalfa CCOMT expressed in Escherichia coli catalyzes O-methylation of caffeoyl and 5-hydroxyferuloyl CoA, with preference for caffeoyl CoA. It has low activity against the free acids. COMT expressed in E. coli is active against both caffeic and 5-hydroxyferulic acids, with preference for the latter compound. Surprisingly, very little extractable O-methyltransferase activity versus 5-hydroxyferuloyl CoA is present in alfalfa stem internodes, in which relative O-methyltransferase activity against 5-hy-droxyferulic acid increases with increasing maturity...

Tobacco O-Methyltransferases Involved in Phenylpropanoid Metabolism. The Different Caffeoyl-Coenzyme A/5-Hydroxyferuloyl-Coenzyme A 3/5-O-Methyltransferase and Caffeic Acid/5-Hydroxyferulic Acid 3/5-O-Methyltransferase Classes Have Distinct Substrate Specificities and Expression Patterns1

Maury, Stéphane; Geoffroy, Pierrette; Legrand, Michel
Fonte: American Society of Plant Physiologists Publicador: American Society of Plant Physiologists
Tipo: Artigo de Revista Científica
Publicado em /09/1999 EN
Relevância na Pesquisa
46.24%
The biosynthesis of lignin monomers involves two methylation steps catalyzed by orthodiphenol-O-methyltransferases: caffeic acid/5-hydroxyferulic acid 3/5-O-methyltransferases (COMTs) and caffeoyl-coenzyme A (CoA)/5-hydroxyferuloyl-CoA 3/5-O-methyltransferases (CCoAOMTs). Two COMT classes (I and II) were already known to occur in tobacco (Nicotiana tabacum) and three distinct CCoAOMT classes have now been characterized. These three CCoAOMT classes displayed a maximum level of expression at different stages of stem development, in accordance with their involvement in the synthesis of lignin guaiacyl units. Expression profiles upon tobacco mosaic virus infection of tobacco leaves revealed a biphasic pattern of induction for COMT I, COMT II, and CCoAOMTs. The different isoforms were expressed in Escherichia coli and our results showed that CCoAOMTs and, more surprisingly, COMTs efficiently methylated hydroxycinnamoyl-CoA esters. COMT I was also active toward 5-hydroxyconiferyl alcohol, indicating that COMT I that catalyzes syringyl unit synthesis in planta may operate at the free acid, CoA ester, or alcohol levels. COMT II that is highly inducible by infection also accepted caffeoyl-CoA as a substrate, thus suggesting a role in ferulate derivative deposition in the walls of infected cells. Tobacco appears to possess an array of O-methyltransferase isoforms with variable efficiency toward the diverse plant o-diphenolic substrates.

Hydroxycinnamoyltransferases Involved in the Accumulation of Caffeic Acid Esters in Gametophytes and Sporophytes of Equisetum arvense.

Hohlfeld, M.; Veit, M.; Strack, D.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /08/1996 EN
Relevância na Pesquisa
35.94%
Four hydroxycinnamoyltransferases from Equisetum arvense L. were studied that catalyze the formation of mono-O-caffeoyl-meso-tartrate, di-O-caffeoyl-meso-tartrate, 5-O-caffeoylshikimate (dactylifrate), and 5-O-caffeoylquinate (chlorogenate). The enzymes were classified as coenzyme A (CoA)-ester-dependent acyltransferases (EC 2.3.1), i.e. hydroxycinnamoyl-CoA:meso-tartrate hydroxycinnamoyltransferase (CTT), hydroxycinnamoyl-CoA:caf-feoyl-meso-tartrate hydroxycinnamoyltransferase (CCT), hydroxycinnamoyl-CoA:shikimate hydroxycinnamoyltransferase (CST), and hydroxycinnamoyl-CoA:quinate hydroxycinnamoyltransferase. The CTT, CCT, and CST were partially purified and separated from E. arvense gametophytes by hydrophobic interaction chromatography on Fractogel TSK Butyl-650 followed by molecular exclusion on fast protein liquid chromatography-Superdex-75 with 87-, 62-, and 130- fold enrichments and 12, 8, and 11% yields, respectively. The enzyme activities obtained with caffeoyl-CoA were 95 (CTT), 74 (CCT), and 200 [mu]kat (CST) kg-1 protein. The apparent native relative molecular weight values were found to be approximately 45,000 (CTT), 52,000 (CCT), and 50,000 (CST). Each enzyme showed highest activities at pH 7.5, the CCT and CST in Tris-HCl (1.2 and 1.0 M) and the CTT in imidazole-HCl (1.25 M). Enzyme activities were stimulated more than 3-fold by 100 mM ascorbate. The apparent energies of activation (kilojoules mol-1) were calculated to be 56 (CTT)...

Properties and Activity Changes of Chlorogenic Acid:Glucaric Acid Caffeoyltransferase From Tomato (Lycopersicon esculentum) 1

Strack, Dieter; Gross, Wiltrud
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /01/1990 EN
Relevância na Pesquisa
36.38%
A novel acyltransferase from cotyledons of tomato (Lycopersicon esculentum Mill.), which catalyzes the transfer of caffeic acid from chlorogenic acid (5-O-caffeoylquinic acid) to glucaric and galactaric acids, was purified with a 2400-fold enrichment and a 4% recovery. The enzyme showed specific activities (theoretical Vmax per milligram of protein) of 625 nanokatals (caffeoylglucaric acid formation) and 310 nanokatals (caffeoylgalactaric acid formation). On sodium dodecyl sulfate-polyacrylamide gel electrophoresis it gave an apparent Mr of 40,000, identical to the value obtained by gel filtration column chromatography. Highest activity was found at pH 5.7, which was constant over a range of 20 to 120 millimolar K-phosphate. The isoelectric point of the enzyme was at pH 5.75. The reaction temperature optimum was at 38°C and the apparent energy of activation was calculated to be 57 kilojoules per mole. The apparent Km values were 0.4 millimolar for glucaric acid, 1.7 millimolar for galactaric acid, and with both acceptors as second substrates 20 millimolar for chlorogenic acid. The relative ratio of the Vmax/Km values for glucaric acid and galactaric acid was found to be 100:12. Substrate-competition experiments support the conclusion that one single enzyme is responsible for both the glucaric and galactaric acid ester formation with marked preference for glucaric acid. It is proposed that the enzyme be called chlorogenic acid:glucaric acid O-caffeoyltransferase (EC 2.3.1.-). The three caffeic acid-dependent enzyme activities involved in the formation of the glucaric and galactaric acid esters...

Plant-derived phenolic compounds prevent the DNA single-strand breakage and cytotoxicity induced by tert-butylhydroperoxide via an iron-chelating mechanism.

Sestili, Piero; Diamantini, Giuseppe; Bedini, Annalida; Cerioni, Liana; Tommasini, Ilaria; Tarzia, Giorgio; Cantoni, Orazio
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 15/05/2002 EN
Relevância na Pesquisa
36.3%
The protective effects of selected members from a series of caffeic acid esters and flavonoids were tested in various toxicity paradigms using U937 cells, previously shown to be sensitive to either iron chelators or bona fide radical scavengers or to both classes of compounds. It was found that all the protective polyphenols were active at very low concentrations and that their effects were observed only under those conditions in which iron chelators also afforded protection. Consistently, active polyphenolic compounds, unlike the inactive ones, effectively chelated iron in an in vitro system. It follows that, at least under the experimental conditions utilized in the present study, the most prominent activity of these polyphenolic compounds resides in their ability to chelate iron. Further studies revealed that the protective effects afforded by the caffeic acid esters and flavonoids were largely mediated by the catechol moiety and that the relative biological potency of these compounds was a direct function of their lipophilicity.

(E)-N-Butyl-3-(3,4-dihy­droxy­phen­yl)acryl­amide hemihydrate

Han, Yan; Hao, Mi-Hua
Fonte: International Union of Crystallography Publicador: International Union of Crystallography
Tipo: Artigo de Revista Científica
Publicado em 17/02/2012 EN
Relevância na Pesquisa
26.4%
In the title compound, C13H17NO3·0.5H2O, a new caffeic acid amide derivative, the solvent water mol­ecule lies on a twofold axis and the terminal ethyl group appears disordered with occupancy factors of 0.525 (6) and 0.475 (6). The benzene ring makes an angle of 17.3 (2)° with the C=C—C—O linker. The presence of an ethyl­enic spacer in the caffeic acid amide mol­ecule allows the formation of a conjugated system, strongly stabilized through π-electron delocalization. The C=C double bond in the linker is trans, similar to those previously reported in caffeic esters. The crystal is stabilized by O—H⋯O, N—H⋯O and C—H⋯O hydrogen bonds. The mol­ecules of the caffeic acid amide form a supermolecular planar structure through O—H⋯O hydrogen bonds between a hy­droxy group of one caffeic acid mol­ecule and a carbonyl O atom of another. These planes inter­act via C—H⋯O, O—H⋯O and N—H⋯O hydrogen bonds to form a three-dimensional network.

Induction of apoptosis by a potent caffeic acid derivative, caffeic acid undecyl ester, is mediated by mitochondrial damage in NALM-6 human B cell leukemia cells

TOMIZAWA, AYAKO; KANNO, SYU-ICHI; OSANAI, YUU; GOTO, AKANE; SATO, CHIZURU; YOMOGIDA, SHIN; ISHIKAWA, MASAAKI
Fonte: D.A. Spandidos Publicador: D.A. Spandidos
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
56.45%
Caffeic acid esters have various biological activities, and we previously reported that undecyl caffeate (caffeic acid undecyl ester, CAUE), a new caffeic acid derivative, has strong pharmacological activity. The present study investigated the cytotoxicity of both CAUE and its parent compound, caffeic acid phenethyl ester (CAPE), and characterized the mechanisms by which they induce apoptosis in the human B cell leukemia cell line NALM-6. Treatment with CAUE reduced cell survival in NALM-6 cells but had no significant effect on the survival of normal lymphocytes. When assessing the 50% inhibitory concentration (IC50) for cytotoxicity, CAUE had 10-fold higher activity than CAPE in NALM-6 cells. CAUE treatment resulted in induction of apoptotic features in NALM-6 cells, including cleaved poly (ADP-ribose) polymerase and activated caspase-3. A caspase inhibitor completely blocked CAUE-induced apoptosis. CAUE treatment resulted in a concentration- and time-dependent decrease in both mitochondrial membrane potential and downregulation of Bcl-2 expression. Moreover, CAUE-induced apoptosis was enhanced in the Bcl-2 knockdown condition induced by small interfering RNA. These data suggest that CAUE-induced apoptosis was mediated via an apoptotic intrinsic pathway including mitochondrial damage and was caspase-dependent. These data also suggest that CAUE is a powerful anti-leukemic agent that acts via induction of apoptosis by mitochondrial damage and selective action in leukemia cells.

Antioxidant effect of mono- and dihydroxyphenols in sunflower oil with different levels of naturally present tocopherols

Hrádková, Iveta; Merkl, Roman; Šmidrkal, Jan; Kyselka, Jan; Filip, Vladimír
Fonte: Blackwell Publishing Ltd Publicador: Blackwell Publishing Ltd
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
26.57%
Antioxidant properties of mono- and dihydroxyphenolic acids and their alkyl esters were examined, with emphasis on the relationship between their molecular structure and antioxidant activity. Test media with different tocopherol level were used for determining the oxidative stability: original refined sunflower oil (total tocopherols 149.0 mg/kg), partially tocopherol-stripped sunflower oil (total tocopherols 8.7 mg/kg) and distilled fatty acid methyl esters (FAME) as a tocopherol-free medium. The chemical reaction of tocopherols with diazomethane tested for the purpose to eliminate their antioxidant activity failed due to the negligible degree of methylation of hydroxyl group in the tocopherol molecule. Caffeic acid and protocatechuic acid (3,4-dihydroxyphenolic acids) and their alkyl esters were found to be more active antioxidants than monohydroxyphenolic acid (p-hydroxybenzoic acid), 2,5-dihydroxyphenolic acid (gentisic acid), 3-methoxy-4-hydroxyphenolic acids (vanillic and ferulic acids) and their corresponding alkyl esters. Naturally present tocopherols in refined sunflower oil proved to have a synergistic effect on gentisic acid but not on its alkyl esters. In contrast, tocopherols showed an antagonistic effect on alkyl esters of caffeic acid...

Synthesis, Evaluation of Anticancer Activity and QSAR Study of Heterocyclic Esters of Caffeic Acid

Hajmohamad Ebrahim Ketabforoosh, Shima; Amini, Mohsen; Vosooghi, Mohsen; Shafiee, Abbas; Azizi, Ebrahim; Kobarfard, Farzad
Fonte: Shaheed Beheshti University of Medical Sciences Publicador: Shaheed Beheshti University of Medical Sciences
Tipo: Artigo de Revista Científica
Publicado em //2013 EN
Relevância na Pesquisa
56.68%
Caffeic acid phenethyl ester (CAPE) suppresses the growth of transformed cells such as human breast cancer cells, hepatocarcinoma , myeloid leukemia, colorectal cancer cells, fibrosarcoma, glioma and melanoma. A group of heterocyclic esters of caffeic acid was synthesized using Mitsunobu reaction and the esters were subjected to further structural modification by electrooxidation of the catechol ring of caffeic acid esters in the presence of sodium benzenesulfinate and sodium toluensulfinate as nucleophiles. Both heterocyclic esters of caffeic acid and their arylsulfonyl derivatives were evaluated for their cytotoxic activity against HeLa, SK-OV-3, and HT-29 cancer cell lines.

Synthesis and effects of new caffeic acid derivatives on nitric oxide production in lipopolysaccharide-induced RAW 264.7 macrophages

Zhang, Jie; Xu, Liu-Xin; Xu, Xu-Sheng; Li, Bo-Wei; Wang, Rui; Fu, Jian-Jun
Fonte: e-Century Publishing Corporation Publicador: e-Century Publishing Corporation
Tipo: Artigo de Revista Científica
Publicado em 15/04/2014 EN
Relevância na Pesquisa
56.17%
In this study, 20 new derivatives of caffeic acid esters were synthesized and their inhibitory activities against the lipopolysaccharide (LPS)-induced nitric oxide (NO) production in RAW264.7 macrophages were determined. Compounds 3l, 3r, 3s and 3t were found to decrease nitrite levels in a dose-dependent manner in LPS-induced cells and showed potent inhibitory activities against the NO production in RAW264.7 macrophages with IC50 values of 7.4, 5.9, 3.3 and 2.2 μM, respectively. They could be selected as compromising compounds for the later pharmacological study.

Clicked Cinnamic/Caffeic Esters and Amides as Radical Scavengers and 5-Lipoxygenase Inhibitors

Doiron, Jérémie A.; Métayer, Benoît; Richard, Ryan R.; Desjardins, Dany; Boudreau, Luc H.; Levesque, Natalie A.; Jean-François, Jacques; Poirier, Samuel J.; Surette, Marc E.; Touaibia, Mohamed
Fonte: Hindawi Publishing Corporation Publicador: Hindawi Publishing Corporation
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
26.53%
5-Lipoxygenase (5-LO) is the key enzyme responsible for the conversion of arachidonic acid to leukotrienes, a class of lipid mediators implicated in inflammatory disorders. In this paper, we describe the design, synthesis, and preliminary activity studies of novel clicked caffeic esters and amides as radical scavengers and 5-LO inhibitors. From known 5-LO inhibitor 3 as a lead, cinnamic esters 8a–h and amides 9a–h as well as caffeic esters 15a–h and amides 16a–h were synthesized by Cu(I)-catalyzed [1,3]-dipolar cycloaddition with the appropriate azide precursors and terminal alkynes. All caffeic analogs are proved to be good radical scavengers (IC50: 10–20 μM). Esters 15g and 15f possessed excellent 5-LO inhibition activity in HEK293 cells and were equipotent with the known 5-LO inhibitor CAPE and more potent than Zileuton. Several synthesized esters possess activities rivaling Zileuton in stimulated human polymorphonuclear leukocytes.

Caffeic acid esters and triterpenes of Alibertia macrophylla

Bolzani, Vanderlan da Silva; Trevisan, Lígia M.V.; Young, M.Claudia M.
Fonte: Elsevier B.V. Publicador: Elsevier B.V.
Tipo: Artigo de Revista Científica Formato: 2089-2091
ENG
Relevância na Pesquisa
86.56%
A hydroalcoholic extract of the leaves of Alibertia macrophylla afforded the esters of caffeic acid and 2-phenylethanol or 2-methyl butane-1,4-diol. The leaves also contain caffeic acid. The acetone extract of the stems of A. macrophylla contain α-amyrin, β-amyrin, α-amyrenone, β-amyrenone, lupeol, lupenone and germanicone. Structural assignments were taken through spectral data analysis and physical properties. This is the first report on the chemistry of Alibertia. © 1991.

Caffeoyl esters of threonic acid and its lactone from Viguiera Pazensis

Uriburu,María L; Gil,Roberto R; Sosa,Virginia E; de la Fuente,Juana R
Fonte: The Journal of Argentine Chemical Society Publicador: The Journal of Argentine Chemical Society
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2008 EN
Relevância na Pesquisa
46.19%
Two caffeoyl esters of sugar derivatives: 3-O-caffeoyl-2-C-methyl-D-threono-1,4-lactone, 4-O-caffeoyl-2-C-methyl-D-threonic acid, along with the previously known compounds: 2-C-methyl-D-threono-1,4-lactone, caffeic acid, carabrone, 5,7,3'-trihydroxy-4'-methoxyflavone, and 5,7,3'-trihydroxy-6,4'-dimethoxyflavone were isolated from the aerial parts of Viguiera pazensis. Their structures were elucidated by application of various spectroscopic methods, including 1D and 2D NMR spectroscopy.