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Search Results: 1 - 10 of 236826 matches for " Alberto C.;Guilhon "
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Stilbenes from Deguelia rufescens var. urucu (Ducke) A. M. G. Azevedo leaves: effects on seed germination and plant growth
Lobo, Lívia T.;Silva, Geilson A. da;Freitas, Manolo C. C. de;Souza Filho, Antonio Pedro S.;Silva, Milton N. da;Arruda, Alberto C.;Guilhon, Giselle M. S. P.;Santos, Lourivaldo S.;Santos, Alberdan S.;Arruda, Mara S. P.;
Journal of the Brazilian Chemical Society , 2010, DOI: 10.1590/S0103-50532010001000007
Abstract: the amazon biodiversity may provide plants whose chemical substances are capable of controlling weeds. in this study we report the isolation and identification of five stilbenes from the leaves of "timbó vermelho" (deguelia rufescens var. urucu): 4-methoxylonchocarpene (1); 3,5-dimethoxy-4′-hydroxy-3′-prenyl-trans-stilbene (2), lonchocarpene (3), 3,5-dimethoxy-4′-o-prenyl-trans-stilbene (4) and pterostilbene (5). compounds 2 and 4 are new natural products although 2 has been previously cited as synthesis product. potential allelopathic activity for 1, 2 and 4 was evaluated over seed germination and plant growth of mimosa pudica weed. the observed effects on seed germination did not vary significantly (p > 0.05) when the analysis of phytotoxicity was performed with the substances alone, the maximum inhibition did not exceed 20%. the most intense inhibitions on radicle and hypocotyl development were found for compound 4 (p < 0.05). when tested in pairs, showed antagonism for seed germination and synergism for radicle and hypocotyl development.
Dihydroflavonols from the leaves of Derris urucu (Leguminosae): structural elucidation and DPPH radical-scavenging activity
L?bo, Lívia T.;Silva, Geilson A. da;Ferreira, Malisson;Silva, Milton N. da;Santos, Alberdan S.;Arruda, Alberto C.;Guilhon, Giselle M. S. P.;Santos, Lourivaldo S.;Borges, Rosivaldo dos Santos;Arruda, Mara Silvia P.;
Journal of the Brazilian Chemical Society , 2009, DOI: 10.1590/S0103-50532009000600013
Abstract: derris urucu is an amazonian plant with insecticide and ichthyotoxic properties. studies with this species show the presence of flavonoids, mainly rotenoids, as well as stilbenes. the ethanol extract of the leaves of derris urucu (leguminosae) afforded three new dihydroflavonols named urucuol a (1), b (2) and c (3), and the dihydroflavonol isotirumalin (4). their structures were elucidated by extensive analysis of 1d and 2d nmr, uv and ir spectra and ms data and comparison with literature data. the isolated compounds (1-4) were evaluated for dpph? radical scavenging activity and showed a relatively lower antioxidant ability compared to the commercial antioxidant trans-resveratrol.
Antraquinonas e naftoquinonas do caule de um espécime de reflorestamento de Tectona grandi (Verbenaceae)
Moreira, Rafael Y.O.;Arruda, Mara S.P.;Arruda, Alberto C.;Santos, Lourivaldo S.;Müller, Adolfo H.;Guilhon, Giselle M.S.P.;Santos, Alberdan S.;Terezo, Evaristo;
Revista Brasileira de Farmacognosia , 2006, DOI: 10.1590/S0102-695X2006000300017
Abstract: the hexane extract of the bark of tectona grandis (verbenaceae) afforded two anthraquinones and two naphtoquinones. their caracterizations were obtained through nmr spectroscopic techniques. this is the first phytochemical study of the bark of tectona grandis reforestation specimen in brazil. the main interest in this work is proving the presence of tectoquinone in reforestation specimen.
Biflavones and triterpenoids isolated from Ouratea castaneifolia (DC.) Engl., Ochnaceae
Nascimento, Luís Adriano S. do;Guilhon, Giselle M. S. P.;Arruda, Mara S. P.;Santos, Lourivaldo S.;Arruda, Alberto C.;Müller, Adolfo H.;Silva, Milton N. da;Rodrigues, Silvane T.;Carvalho, Mário G. de;
Revista Brasileira de Farmacognosia , 2009, DOI: 10.1590/S0102-695X2009000600004
Abstract: this paper presents the chemical investigation of the leaves and stems of ouratea castaneifolia (dc.) engl.. there are no chemical or pharmacological studies with this species. classic phytochemical investigation of the organic extracts together with high pressure liquid chromatography (hplc) procedures lead to the identification of seventeen metabolites: seven triterpenes (friedelin, 3β-friedelinol, α-amyrin, β-amyrin, lupeol, germanicol and taraxerol), four steroids (sitosterol, stigmasterol and the glycosides sitosteryl 3-o-β-d-glucopyranoside and stigmasteryl 3-o-β-d-glucopyranoside), one isoflavone (5,7,4'-trimethoxyisoflavone), one flavone (5,4'-dihydroxy-7,3',5'-trimethoxyflavone) and four biflavones (amenthoflavone, 7,7"-o-dimethylamenthoflavone, heveaflavone and tetramethylamenthoflavone). the structures of the compounds were established by the analysis of 1h, 13c nmr spectra including bidimensional techniques. the classes of the identified metabolites are in agreement with previous studies of the ouratea genus.
O Brasil e os chamados blocos regionais
S?o Paulo em Perspectiva , 2002, DOI: 10.1590/S0102-88392002000100004
Abstract: contrary to expectations, the formation of competing trade blocks has not become a reality. today, brazil has the opportunity to play a larger role in two regional associations ? the ftaa and mercosul ? as well as in the inter-regional arrangement between mercosul and the european union. ftaa membership is the most important of the three, providing as it would a point of reference from which brazil can define its role in the world.
Da crian a ao menor
José Augusto Guilhon Albuquerque
Psicologia: Ciência e Profiss?o , 1986, DOI: 10.1590/s1414-98931986000200012
Dupla les?o pontina de fisher
Guilhon, Fernando;Vieira, Lea F.;
Arquivos de Neuro-Psiquiatria , 1986, DOI: 10.1590/S0004-282X1986000300006
Abstract: c. miller fisher described separately two pontine syndromes, that he called "the one-and-a-half syndrome" and "ataxic hemiparesis". the authors report the case of a woman who developed simultaneously the two syndromes, caused by a stroke of pontine localization, and comment about the structures involved by the lesion.
Flavonoids and Other Compounds from Ouratea ferruginea (Ochnaceae) as Anticancer and Chemopreventive Agents
Queli C. Fidelis,Rosane N. Castro,Giselle M. S. P. Guilhon,Silvane T. Rodrigues,Cristiane M. C. de Salles,Jo?o B. de Salles,Mario G. de Carvalho
Molecules , 2012, DOI: 10.3390/molecules17077989
Abstract: The chemical study of the extracts from leaves and stems of Ouratea ferruginea allowed the identification of a new isoflavone, 5-hydroxy-7,3′4′5′-tetramethoxyisoflavone, and twenty two known compounds, including friedelin, 3β-friedelinol, lupeone, a mixture of sitosterol, stigmasterol and campesterol, sitosteryl- and stigmasteryl-3-O-b-D-glucopyranosides, 5,4′-dihydroxy-7,5′,3′-trimethoxyisoflavone, 5,4′-dihydroxy-7,3′-di-methoxyisoflavone (7,3′-di-O-methylorobol), 5,7,4′-trihydroxy-3′,5′-dimethoxyisoflavone (piscigenin), 2R,3R-epicatechin, syringic acid, 2,6-dimethoxybenzoquinone, 2,6-dimethoxyhydroquinone, syringic and ferulic aldehyde, a mixture of vanillic acid, 1-hydroxy-2-methoxy-4-(1E-3-hydroxy-1-propenyl)-benzene and 3,5-dimethoxy-4-hydroxy-dihydrocinamaldehyde, besides amenthoflavone and 7-O-methylamenthoflavone (sequoiaflavone) which are considered as chemotaxonomic markers of Ouratea. The structures were identified by IR, 1H- and 13C-NMR and GC-MS, HPLC-MS, besides comparison with literature data. The inhibitory effects of 5,4′-dihydroxy-7,5′,3′-trimethoxyisoflavone, 7,3′-di-O-methylorobol, piscigenin and 7-O-methylamenthoflavone on cytochrome P450-dependent 7-ethoxycoumarin O-deethylase (ECOD) and glutathione S-transferase (GST) were evaluated in vitro. The 5,4′-dihydroxy-7,5′,3′-trimethoxy-isoflavone was the best inhibitor, inhibiting almost 75% of GST activity. Sequoiaflavone was the most potent inhibitor, inhibiting ECOD assay in 75%. These activities allow us to consider both these flavonoids as potential anticancer and chemopreventive agents.
Anti-inflammatory and opioid-like activities in methanol extract of Mikania lindleyana, sucuriju
Vanderlinde, Frederico A.;Rocha, Fabio F.;Malvar, David C.;Ferreira, Raquel T.;Costa, Elson A.;Florentino, Iziara F.;Guilhon, Giselle M. S. P.;Lima, Thereza C. M. de;
Revista Brasileira de Farmacognosia , 2012, DOI: 10.1590/S0102-695X2011005000190
Abstract: mikania lindleyana dc., asteraceae (sucuriju), grows in the amazon region, where is frequently used to treat pain, inflammatory diseases and scarring. this study was carried out to investigate phytochemical profile accompanied by in vivo antinociceptive and anti-inflammatory screening of n-hexane (he), dichloromethane (dme) and methanol (me) extracts obtained from the aerial parts of the plant. the oral administration of me (0.1, 0.3, 1 g/kg) caused a dose-related reduction (16.2, 42.1 e 70.2%) of acetic acid-induced abdominal writhing while he and dme (1 g/kg, p.o.) were ineffective. in the hot plate test, me (300 mg/kg, p.o.) increased the latency of heat stimulus between 30 and 120 min and inhibited the first (45%) and second (60%) phases of nociception in the formalin test. the antinociception induced by me or positive control fentanyl (150 μg/kg, s.c.) in hot plate and formalin tests was prevented by naloxone (3 mg/kg, s.c.). when submitted to the carrageenan-induced peritonitis test, me (0.5, 1.0, 2.0 g/kg, p.o.) impaired leukocyte migration into the peritoneal cavity by 46.8, 59.4 and 64.8% respectively, while positive control dexamethasone (2 mg/kg, s.c.), inhibited leukocyte migration by 71.1%. these results indicate that the antinociception obtained after oral administration of methanol extract of m. lindleyana involves anti-inflammatory mechanisms accompanied with opioid-like activity which could explain the use of the specie for pain and inflammatory diseases.
Atividade potencialmente alelopática do óleo essencial de Ocimum americanum
Souza Filho, A.P.S.;Bayma, J.C.;Guilhon, G.M.S.P.;Zoghbi, M.G.B.;
Planta Daninha , 2009, DOI: 10.1590/S0100-83582009000300010
Abstract: essential oils are known for their several biological activities. the biodiversity of the amazon region is rich in essential-oil producing plants.the aim of this work was to study the potentially allelopathic activity of the essential oil of ocimum americanum and to determine its effects on seed germination and growth of two weed species. solutions of the essential oil were tested at concentrations varying from 100 to 2,000 mg l-1, considering their effects on seed germination (at 25 oc and a photoperiod of 12 hours) and radicle and hypocotyl growth (at 25 oc and a photoperiod of 24 hours) of the weeds mimosa pudica and senna obtusifolia. factors related to concentration, specificity of the receiving plants and the parameters analyzed were decisive for the effects obtained. overall, there was a positive relation between concentration and inhibitory effect. m. pudica tended to be more sensitive to the effects than s. obtusifolia. seed germination was more affected by the essential oil, followed by radicle elongation and hypocotyl elongation. the observed effects can be attributed to the composition of the essential oil, that includes monoterpenes, sesquiterpenes, aliphatic compounds and phenylpropanoids. the compounds limonene, camphor and linalol, found in the essential oil, are known to have allelopathic activity.
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