DEFAR - Artigos publicados em periódicos
URI permanente para esta coleçãohttp://www.hml.repositorio.ufop.br/handle/123456789/531
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Resultados da Pesquisa
Item Constituintes químicos e efeito ecotoxicológico do óleo volátil de folhas de Eucalyptus urograndis (Mirtaceae).(2010) Araújo, Fabíola Oliveira Lino de; Rietzler, Arnola Cecília; Duarte, Lucienir Pains; Silva, Grácia Divina de Fátima; Carazza, Fernando; Vieira Filho, Sidney AugustoThe volatile oil from the leaves of E. urograndis was analyzed by GC and GC-MS. It was identified 10 compounds in which, orto-cimene (41.4%) and 1,8-cineol (25.8%) were the main constituents. The induction of deleterious effect to aquatic organisms due to the presence of volatile oil lixiviated from E. urograndis leaves was studied using Daphnia laevis and D. similis as bioindicators. Through the results of toxicological tests it was possible to show that the litterbag of E. urograndis represents a risk factor for the aquatic ecosystem of lakes and rivers that are in the surrounding area of large scale Eucalyptus plantations. The method can be used for monitor the quality of these types of aquatic environments.Item Complete assignment of the 1H and 13C NMR spectra of a new polyester sesquiterpene from Austroplenckia populnea.(2000) Vieira Filho, Sidney Augusto; Duarte, Lucienir Pains; Santos, Marcelo Henrique dos; Silva, Grácia Divina de Fátima; Lula, Ivana Silva; Afonso, Robson José de Cássia Franconew polyester sesquiterpene (4-hydroxy-1,2,6,15-tetraacetyl-9-benzoylagarofuran), together with known friedelane triterpenes (friedelin, -friedelinol and 28-hydroxyfriedelin), was isolated from the leaves of Austroplenckia populnea. The structure and relative stereochemistry of the new ester were based on 2D NMR spectroscopic techniques including HMBC, HMQC and NOESY.Item Selective oxidation of lupeol by iodosylbenzene catalyzed by manganese porphyrins.(2016) Martins, Dayse Carvalho da Silva; Silva, Fernando César; Meireles, Alexandre Moreira; Soares, Érico Augusto Rodrigues; Silva, Grácia Divina de Fátima; Vieira Filho, Sidney Augusto; Duarte, Lucienir Pains; Rebouças, Júlio Santos; Idemori, Ynara MarinaManganese porphyrin-catalyzed oxidation of lupeol by iodosylbenzenewas achieved undermild conditionswith low isolated yields but with remarkable selectivity, depending on the catalyst of choice. Mn(III) mesotetraphenylporphyrin and Mn(III) meso-tetrakis(4-carbomethoxyphenyl)porphyrin provided an entry for the preparation of 3β,30-dihydroxylup-20(29)-ene (6–14% yields), whereas Mn(III) β-octabromo-meso-tetrakis(4- carbomethoxyphenyl)porphyrin led to 20-oxo-3β-hydroxy-29-norlupeol (6% yield), as single products. Unreacted lupeol was recovered in quantitative yield. The oxidative transformations at lupeol C20 or C30 take place with no need for protection of C3 hydroxyl moiety.Item Anti-inflammatory, antimicrobial and acetylcholinesterase inhibitory activities of friedelanes from Maytenus robusta branches and isolation of further triterpenoids.(2017) Sousa, Grasiely Faria de; Aguilar, Mariana Guerra de; Dias, Danielle Ferreira; Takahashi, Jacqueline Aparecida; Moreira, Maria Eliza de Castro; Vieira Filho, Sidney Augusto; Silva, Grácia Divina de Fátima; Rodrigues, Salomão Bento Vasconcelos; Messias, Maria Cristina Teixeira Braga; Duarte, Lucienir PainsThe new pentacyclic triterpenoids friedel-1-en-3,16-dione (1), 1α,29-dihydroxyfriedelan-3-one (2) and 16β,28,29-trihydroxyfriedelan-3-one (3) were isolated from Maytenus robusta branches in addition to the known, but new for this species, triterpenoid 12α,29-dihydroxyfriedelan-3-one (4). The structures and stereochemistry of the novel triterpenoids were established by IR, 1D/2D NMR and HR-APCIMS spectral data. In addition, the biological activity of compound 2 and the previously isolated friedelanes 5–8 (friedelan-3,16-dione, 29-hydroxyfriedelan- 3-one, 29-hydroxyfriedelan-3,16-dione and 16β,29-dihydroxyfriedelan-3-one) was investigated. Compounds 2 and 8 were tested for their acetylcholinesterase properties and antimicrobial activity against the bacteria Staphylococcus aureus, Pseudomonas aeruginosa, Listeria monocytogenes, Citrobacter freundii, and the fungus Candida albicans. Compound 2 was the most active compound for both assays, with values of 32.3% acetylcholinesterase inhibition, 42% activity against the fungus Candida albicans and 34% against the bacterium Pseudomonas aeruginosa. Compounds 5–8 were assayed for their antiedematogenic activity using the carrageenan- induced paw edema assay. At maximum inflammation after three hours, compounds 6 and 8 showed 42% and 57% activity, respectively. After four hours, compounds 5 and 7 showed activity of 71% and 75% compared to 79% of the control indomethacin.Item Flavonol triglycosides of leaves from Maytenus robusta with acetylcholinesterase inhibition.(2017) Sousa, Grasiely Faria de; Aguiar, Mariana Guerra de; Takahashi, Jacqueline Aparecida; Alves, Tânia Maria de Almeida; Kohlhoff, Markus; Vieira Filho, Sidney Augusto; Silva, Grácia Divina de Fátima; Duarte, Lucienir PainsAlthough Maytenus robusta aqueous infusions of leaves are used in Brazilian traditional medicine for stomach disease treatment, only a few chemical studies of this species are found in literature. The phytochemical investigation of methanol extract from M. robusta leaves yielded the known compound kaempferol (3) and two new flavonol glycosides: kaempferol-3-O-b-D-glucopyranosyl-(1 !3)-a-Lrhamnopyranosyl-( 1 ! 2)-b-D-glucopyranoside (1) and quercetin-3-O-b-D-glucopyranosyl-(1 !3)-a-Lrhamnopyranosyl-( 1 ! 2)-b-D-glucopyranoside (2). The chemical structures of 1 and 2 were elucidated by 1D/2D NMR, ESI–MS and ESI–MS2 spectral data. It is the first time flavonoids have been reported from M. robusta. Flavonols 1 and 2 showed 66% and 80% acetylcholinesterase (AChE) inhibition, compared to 93% of the standard eserine, by the Ellman’s method. These substances are one of the few active flavonols linked to a trisaccharide chain in the literature presenting this activity, and contribute to the screening for new types of natural AChE inhibitors.Item Cytotoxicity, anti-poliovirus activity and in silico biological evaluation of constituents from Maytenus gonoclada (Celastraceae).(2014) Oliveira, Mauro Lúcio Gonçalves de; Assenço, Regina Aparecida Gomes; Silva, Grácia Divina de Fátima; Lopes, Júlio César Dias; Silva, Fernando César; Lanna, Maria Célia da Silva; Magalhães, José Carlos de; Duarte, Lucienir Pains; Vieira Filho, Sidney AugustoObjective: The in silico free access web tools PASS online and ChemMapper were used to predict potential biological activities of compounds 1 to 8 isolated from Maytenus gonoclada (Celastraceae). The constituents 4’-O-methylepigalocatequin (6), tingenone (7) and proanthocyanidin A (8), and ethanolic extracts were subjected to in vitro cytotoxicity using VERO cells and anti-Poliovirus assays. Methods: QSAR and molecular superposition, correlating the average number of pharmacophores were used in the prediction studies. Cellular line VERO ATCC CCL-81 was used to determine anti-Poliovirus effect, observed by colorimetric (MTT) method. The annexing V/propidium iodide assay was used to determine the occurrence of apoptosis in the cytotoxicity assays. Results: The experimental results found for constituents 6-8 were in accordance with observed data obtained through PASS online and ChemMapper simulation. Conclusion: Compound 7 showed higher cytotoxic and apoptosis induction properties, and 6 and 8 presented anti-Poliovirus activity.Item Pentacyclic triterpenes from Maytenus genus as acetylcholinesterase inhibitors.(2014) Rodrigues, Vanessa Gregório; Silva, Fernando César; Duarte, Lucienir Pains; Takahashi, Jacqueline Aparecida; Matildes, Bibiane Lindsay Guimarães; Silva, Grácia Divina de Fátima; Miranda, Roqueline Rodrigues Silva de; Vieira Filho, Sidney AugustoObjective: Species of the Maytenus genus have been used in traditional medicine to treat a wide variety of human diseases. These species represent a promising source of bioactive substances of pharmacological interest. As part of a research project on phytochemical and biological activity studies of the low polarity extracts of the Maytenus genus, the extracts and eleven known pentacyclic triterpenes isolated from roots of Maytenus imbricata, and branches of Maytenus gonoclada were investigated for acetylcholinesterase inhibitory property. Methods: The acetylcholinesterase inhibition was evaluated by direct thin layer chromatography bioautography and microplate assays. Results: The crude extracts did not exhibit acetylcholinesterase inhibitory activity, but pentacyclic triterpenes, 3-oxo-11α-hydroxylup-20(29)-ene, 3-oxo-29-hydroxyfriedelane and 3,7-dioxofriedelane were active when compared to the standard compound physostigmine (eserine). Conclusion: The in vitro acetylcholinesterase inhibition property of these three pentacyclic triterpenes from Maytenus genus gives them the potential compounds to be applied in the treatment of Alzheimer’s disease.Item Samaras of Austroplenckia Populnea (Celastraceae) : new constituents and effect of extracts and friedelin on germination of Bidens Pilosa (Asteraceae).(2014) Caneschi, Carolina Milagres; Souza, Shiara Martins de; Certo, Thais Seixas; Souza, Gustavo Henrique Bianco de; Campos, Michele Soares Tacchi; Duarte, Lucienir Pains; Silva, Grácia Divina de Fátima; Gomes, Marcos de Souza; Vieira Filho, Sidney AugustoObjective: Evaluation of the impact of extracts and constituents from samaras of Austroplenckia populnea on percentage of seed germination (%SG), germination speed index (GSI), length of rootlets (LR), seedling length (SL), and on dry mass (DM) of Bidens pilosa L weed. Methods: The powder of samaras was extracted with organic solvents providing the hexane (SAPEH), chloroform (SAPEC), ethyl acetate (SAPEAE) and ethanol (SAPEE) extracts. The terpene 1 was isolated from SAPEH by means of column and thin layer chromatography and identified through NMR spectroscopy. Each extract and 1 were subjected to growth inhibition assays evaluating the following parameters: %SG, GSI, LR, SL and DM, with five repetitions. Results: The compounds Friedelin (1), 7-hydroxy-clerodan-3-en-16,15:18,20-diolide (2), 3,5,7,4'-tetrahydroxy-6-methoxy-8-prenylflavanone (3), tetradecanamide (4), and 4-hydroxy-1,6,15-acetyloxy-8,9-benzoyloxy-agarofurane (5) were isolated from hexane extract of samaras of A. populnea and identified by spectroscopic data. The compounds 2, 3 and 5 were not previously described as being chemical constituents from Celastraceae family. In addition, the novel compounds 3 and 5 were described here for the first time. Substantial effect on the germination of B. pilosa L. (picãopreto) was observed after treatment of seeds with nonpolar extracts from Samaras of A. populnea. Friedelin inhibited the seed germination in the tested concentrations showing toxic properties against picão-preto. Conclusion: The germination inhibition of seeds was higher using nonpolar extracts than polar extract. Friedelin inhibited the seed germination in the tested concentrations showing toxic properties against B. pilosa.Item Two epimeric friedelane triterpenes isolated from Maytenus truncata Reiss : 1H and 13C chemical shift assignments.(2000) Meléndez Salazar, Gloria Del Carmen; Silva, Grácia Divina de Fátima; Duarte, Lucienir Pains; Lula, Ivana SilvaAn NMR study of 3˛- and 3ˇ-friedelinol is described. In addition to conventional 1D NMR methods, 2D shift-correlated NMR experiments HMQC [(1J(C,H)], HMBC [nJ(C,H); n D 2 and 3] and 2D 1H,1H-NOESY were used for 1H and 13C chemical shift assignments of these triterpenes.Item Triterpene esters isolated from leaves of Maytenus salicifolia Reissek.(2007) Miranda, Roqueline Rodrigues Silva de; Silva, Grácia Divina de Fátima; Duarte, Lucienir Pains; Vieira Filho, Sidney AugustoThe triterpene ester (3b)-olean-18-en-3-yl stearate (1), together with (3b)-urs-12-en-3-yl stearate (2), and (3b)-lup-20(29)-en-3-yl stearate (3) were isolated from leaves of Maytenus salicifolia Reissek (Celastraceae). The structure of 1, a new compound, including its configuration, was established by 1H, 13C, and DEPT-135 NMR data, including 2D experiments( HSQC, HMBC, COSY, and NOESY). The molecular mass (692 Da) was confirmed by gas chromatography coupled with mass spectrometry (CG/ MS).