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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 Chemical constituents of Salacia elliptica (celastraceae).(2010) Duarte, Lucienir Pains; Figueiredo, Rute Cunha; Sousa, Grasiely Faria de; Soares, Débora Barbosa da Silva; Rodrigues, Salomão Bento Vasconcelos; Silva, Fernando César; Silva, Grácia Divina de Fátima; Vieira Filho, Sidney AugustoThe chemical investigation of Salacia elliptica allowed to the isolation of 20 constituents: two polyols, one xanthone, a mixture of long chain hydrocarbons, one carboxylic acid, one polymer, two steroidal compounds, one aromatic ester and eleven pentacyclic triterpenes. These triterpenes include 3β-stearyloxy-oleanane, 3β-stearyloxy-ursane, one seco-friedelane, and eight compounds of the friedelane serie. The chemical structure and the relative configuration of a new triterpene 1,3-dioxo-16α-hydroxyfriedelane (15) were established through 1H and 13C NMR including 2D experiments (HMBC, HMQC, COSY and NOESY) and herein reported for the first time.Item Chemodiversity of essential oils from nine species of Celastraceae.(2020) Duarte, Lucienir Pains; Camargo, Karen Caroline; Vidal, Diogo Montes; Pereira, Hebert Vinicius; Pereira, Rafael César Gonçalves; Aguilar, Mariana Guerra de; Sousa, Grasiely Faria de; Vieira Filho, Sidney Augusto; Simões, Maria O. Mercadante; Messias, Maria Cristina Teixeira Braga; Oliveira, Djalma Menezes deExtracts and compounds obtained from several species of Celastraceae family are reported as potential sources of drugs due to their diverse pharmacological properties. Nevertheless, essential oil composition from these species is still little known. This work aimed the analysis of essential oils obtained from different Brazilian Celastraceae species. A total of seventeen oils were obtained using hydrodistillation process and analyzed by gas chromatography/mass spectrometry (GC/MS). Principal component analysis (PCA) allowed the identification of a chemical composition pattern among the analyzed essential oils. Some compounds were more frequent among Celastraceae species, such as cis and trans-oxide linalool (14/17 oil samples), nerylacetone (13/17), linalool (11/17), β-ionone (10/17), α-ionone (9/17), nerolidol (10/17), decanal (10/17) and dodecanoic acid (10/17). These results contribute to the chemophenetics of Celastraceae species.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 Imines and lactones derived from friedelanes and their cytotoxic activity.(2018) Aguilar, Mariana Guerra de; Sousa, Grasiely Faria de; Evangelista, Fernanda Cristina Gontijo; Sabino, Adriano de Paula; Vieira Filho, Sidney Augusto; Duarte, Lucienir PainsFriedelan-3-one (1) and friedelane-3,16-dione (2) isolated from leaves and branches of Maytenus robusta Reissek were subjected to structural modifications via nucleophilic addition to the carbonyl group and Baeyer-Villiger oxidation in order to synthesize potential cytotoxic compounds. The oximes friedelane-3-hydroxyimino (3) and 3-hydroxyiminofriedelan-16-one (4) together with the lactones friedelane-3,4-lactone (5) and 3,4-lactonefriedelan-16-one (6) were characterized by IR and NMR spectroscopic analyses. Compounds 4 and 6 are reported for the first time. Cytotoxic screening via MTT assay in human leukemia cell lines (THP-1 and K562) demonstrated no significant improvement of compounds 3-6 when compared to the starting materials. Only compounds 3 and 5 demonstrated an improvement against K562 cells. However, the same assay on ovar- ian and breast cancer cell lines (TOV-21G and MDA-MB-231) showed a reduction in the IC50 for compounds 4-6, indicating that ring A modifications may enhance the biological potential.Item New triterpenes from Maytenus robusta : structural elucidation based on NMR experimental data and theoretical calculations.(2012) Sousa, Grasiely Faria de; Duarte, Lucienir Pains; Alcântara, Antônio Flávio de Carvalho; Silva, Grácia Divina de Fátima; Vieira Filho, Sidney Augusto; Miranda, Roqueline Rodrigues Silva de; Oliveira, Djalma Menezes de; Takahashi, Jacqueline AparecidaLeaves of Maytenus robusta (Celastraceae) were subjected to phytochemical investigation mainly directed at the isolation of pentacyclic triterpenes. The compounds friedelin (1), β-friedelinol (2), 3-oxo-21β-H-hop-22(29)-ene (7), 3,4-seco-friedelan-3,11β- olide (8), 3β-hydroxy-21β-H-hop-22(29)-ene (9), 3,4-seco-21β-H-hop-22(29)-en-3-oic acid (10), 3,4-seco-friedelan-3-oic acid (11), and sitosterol were identified in the hexane extract of M. robusta leaves. Compounds 8 and 9 are described herein for the first time. The structure and stereochemistry of both compounds were experimentally established by IR, HRLC-MS, and 1D (1H, 13C, and DEPT 135) and 2D (HSQC, HMBC and COSY) NMR data and supported by correlations with carbon chemical shifts calculated using the DFT method (BLYP/6-31G* level). Compounds 7 and 10 are also described for the first time, and their chemical structures were established by comparison with NMR data of similar structures described in the literature and correlations with BLYP/6-31G* calculated carbon chemical shifts. Compound 9, a mixture of 11 and sitosterol, and 3β,11β-dihydroxyfriedelane (4) were evaluated by the Ellman’s method and all these compounds showed acethylcholinesterase inhibitory properties.Item Pentacyclic triterpenes from branches of Maytenus robusta and in vitro cytotoxic property against 4T1 cancer cells.(2014) Sousa, Grasiely Faria de; Soares, Daniel Crístian Ferreira; Mussel, Wagner da Nova; Pompeu, Nana Flora Elias; Silva, Grácia Divina de Fátima; Vieira Filho, Sidney Augusto; Duarte, Lucienir PainsDois novos friedelanos, 1 e 2, e cinco triterpenos pentacíclicos conhecidos foram isolados dos galhos de Maytenus robusta. Suas estruturas químicas foram identificadas como 3,16-dioxo-29- hidroxifriedelano (1), 3-oxo-16b,29-di-hidroxifriedelano (2), 3-oxofriedelano (3), 3b-friedelinol (4), 3,16-dioxofriedelano (5), 3-oxo-29-hidroxifriedelano (6) e 3,16-dioxo-12a-hidroxifriedelano (7). A estrutura e estereoquímica dos triterpenos 1 e 2 foram estabelecidas por infravermelho (IR), ressonância magnética nuclear (NMR) 1D/2D, espectrometria de massas de alta resolução com ionização química à pressão atmosférica (HR-APCIMS) e difração de raios X de pó. A atividade citotóxica in vitro dos triterpenos 1 a 6 foi avaliada frente a células de câncer de mama murino. Os triterpenos 1 e 2 apresentaram atividade citotóxica contra células 4T1 em baixa concentração.Item Trichomonicidal activity of Maytenus imbricata (Celastraceae).(2014) Batista, Carla Ribeiro Álvares; Fonseca, Thaisa Helena Silva; Rodrigues, Vanessa Gregório; Sousa, Grasiely Faria de; Chacon, Michelle Oliveira; Vieira Filho, Sidney Augusto; Duarte, Lucienir Pains; Gomes, Maria AparecidaTrichomoniasis, most common non-viral sexually transmitted infection worldwide, is produced by protozoan Trichomonas vaginalis. The therapy of choice is metronidazole (MTZ). The drug has undesirable side effects, which may result in treatment discontinuation, leading to further spread of infection and emergence of resistant strains. This feature highlights the importance of studying new trichomonicidal substances. In this context, the importance of plants in relation to the research of new drugs is undeniable. The genus Maytenus, distributed throughout Brazil, is the largest of family Celastraceae, including about 80 recognized species with different biological activities. Therefore, the trichomonicidal activity of MTZ and extracts obtained from Maytenus robusta leaves and Maytenus imbricata roots on the JT strain of T. vaginalis, sensitive (JT) and resistant (JTR) to MTZ was investigated. Sample of T. vaginalis trophozoites were associated with extracts in 6 increasing concentrations ranging from 0.43 to 13.76 μg/ml. The solid that precipitated from the hexane/ethyl ether - 1:1 extract (SEH), obtained from M. imbricata roots proved to be active. This extract also impacted the viability of trophozoites of both strains, with IC50 value surprisingly low (1.09 μg/ml for JT and 1.57 μg/ml for JTR) signaling towards a promising candidate for phytotherapy or for isolation of substance with trichomonicidal activity.Item Truncatin a : triterpene dimer isolated from Maytenus truncata Reissek (Celastraceae).(2021) Meléndez Salazar, Gloria Del Carmen; Sousa, Grasiely Faria de; Duarte, Lucienir Pains; Silva, Roqueline Rodrigues; Vieira Filho, Sidney Augusto; Silva, Grácia Divina de FátimaMaytenus truncata Ressek is a medicinal plant naturally found in Cerrado biome of Brazil. The tea from its leaves is used to treat gastrointestinal disorders. Such as other species of the Celastraceae family, the aerial parts, and roots of Maytenus truncata are rich in pentacyclic triterpenes. Roots of M. truncata were subjected to chromatographic methods that culminated in the isolation of a dimer pentacyclic triterpene termed truncatin. The structure of truncatin was established based on FT-IR, 1D/2D NMR, including DEPT-135, HSQC, HMBC and COSY spectra, and mass spectrometry. The compound was characterized as containing a quinone methide friedelane-type unit linked to another unit constituted by a skeleton similar to those of lupane series. These two units are linked together through the respective ring A, by two ether linkages. This work presents for the first time, the skeleton lupane as a unit of a dimer of pentacyclic triterpenes.Item Virucidal antiviral activity of Maytenus quadrangulata extract against Mayaro virus : evidence for the presence of catechins.(2023) Nunes, Damiana Antônia de Fátima; Lopes, Gabriela Francine Martins; Nizer, Waleska Stephanie da Cruz; Aguilar, Mariana Guerra de; Santos, Felipe Rocha da Silva; Sousa, Grasiely Faria de; Ferraz, Ariane Coelho; Duarte, Lucienir Pains; Brandão, Geraldo Célio; Vieira Filho, Sidney Augusto; Magalhães, Cíntia Lopes de Brito; Ferreira, Jaqueline Maria Siqueira; Magalhães, José Carlos deEthnopharmacological relevance: Mayaro virus (MAYV) is an arbovirus endemic to the Amazon region, which comprises the states of the North and Midwest region of Brazil and encompasses the largest tropical forest in the world, the Amazon Forest. The confirmation of its potential transmission by Aedes aegypti and recent cases in Brazil, mainly in large centers in the northern region, led to the classification of Mayaro fever as an emerging disease. Traditional medicine is commonly used to treat various diseases, mainly by local riverside populations. Some species of the genus Maytenus, which have similar morphologies, are popularly used to treat infections and inflammations. In this context, our research group has studied and confirmed the antiviral activity of several plant-derived compounds. However, several species of this same genus have not been studied and therefore deserve attention. Aim of the study: This study aimed to demonstrate the effects of ethyl acetate extracts of leaves (LAE) and branches (TAE) of Maytenus quadrangulata against MAYV. Materials and methods: Mammalian cells (Vero cells) were used to evaluate the cytotoxicity of the extracts. After cell infection by MAYV and the treatment with the extracts, we evaluated the selectivity index (SI), the virucidal effect, viral adsorption and internalization, and the effect on viral gene expression. The antiviral action was confirmed by quantifying the viral genome using RT-qPCR and by analyzing the effect on virus yield in infected cells. The treatment was performed based on the effective concentration protective for 50% of the infected cells (EC50). Results: The leaves (LAE; EC50 12.0 μg/mL) and branches (TAE; EC50 101.0 μg/mL) extracts showed significative selectivity against the virus, with SI values of 79.21 and 9.91, respectively, which were considered safe. Phytochemical analysis revealed that the antiviral action was associated with the presence of catechins, mainly in LAE. This extract was chosen for the subsequent studies since it reduced the viral cytopathic effect and virus production, even at high viral loads [MOI (multiplicity of infection) 1 and 5]. The effects of LAE resulted in a marked reduction in viral gene expression. The viral title was drastically reduced when LAE was added to the virus before infection or during replication stages, reducing virus production up to 5-log units compared to infected and untreated cells.