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Carlos Alberto Theodoro Siqueira Alessandra Freitas Serain Aislan Cristina Rheder Fagundes Pascoal Nathalia Luiza Andreazza Caroline Caramano de Lourenço Ana Lúcia T. Góis Ruiz 《Natural product research》2015,29(20):1966-1969
Essential oil from the leaves of Guatteria australis was obtained by hydrodistillation, analyzed by Gas Chromatography coupled to Mass Spectromery (GC–MS) and their antiproliferative, antileishmanial, antibacterial, antifungal and antioxidant activities were also evaluated. Twenty-three compounds were identified among which germacrene B (50.66%), germacrene D (22.22%) and (E)-caryophyllene (8.99%) were the main compounds. The highest antiproliferative activity was observed against NCI-ADR/RES (TGI = 31.08 μg/ml) and HT-29 (TGI = 32.81 μg/ml) cell lines. It also showed good antileishmanial activity against Leishmania infantum (IC50 = 30.71 μg/ml). On the other hand, the oil exhibited a small effect against Staphylococcus aureus ATCC 6538, S. aureus ATCC 14458 and Escherichia coli ATCC 10799 (MIC = 250 μg/ml), as well as small antioxidant activity (457 μmol TE/g) assessed through ORACFL assay. These results represent the first report regarding chemical composition and bioactivity of G. australis essential oil. 相似文献
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Mélanie Fonte Natália Fagundes Ana Gomes Ricardo Ferraz Cristina Prudêncio Maria João Araújo Paula Gomes Cátia Teixeira 《Tetrahedron letters》2019,60(17):1166-1169
A multi-step synthetic route towards N4,N9-disubstituted 4,9-diaminoacridines that, to the best of our knowledge, has no precedence in the literature, has been developed. The target structures are likely to reveal interesting biological activities in the near future, not only due to their mepacrine-like core, but also because they embed simultaneously the pharmacophores of chloroquine and primaquine, antimalarial drugs that act at different stages of malaria infection. 相似文献
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In this work we show that homogeneous Neumann boundary conditionsinhibit the Coleman-Weinberg mechanism for spontaneous symmetry breakingin the scalar electrodynamics if the length of the finite region is small enough (a = e2M-1φ, where Mφ is the mass of the scalar field generated by the Coleman-Weinberg mechanism). 相似文献
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Roger Remy Dresch Maria Terezinha Kreinecker Dresch Renata Biegelmeyer Débora Fretes Argenta Ricardo Fagundes da Rocha Helder Ferreira Teixeira 《Natural product research》2018,32(4):486-492
The aim of the present study was to develop a phytocosmetic using Vitis waste by-products, for use as a topical formulation for skin protection against ultraviolet radiation damage. The study also evaluates the free radical scavenger activity of the crude extracts of dried leaves of Vitis vinifera and Vitis labrusca, as well as the anthocyanins, flavonoid fraction and isolated compounds. Next, release and permeation studies of hydrogels were performed using Franz-type diffusion cells. Flavonoid acted more intensively in TRAP and conjugated dienes antioxidant assays, whereas anthocyanins had higher antioxidant activity in hydroxyl and nitric oxide assay. Only quercetin-3-O-glucuronide (5) was released from hydrogels, and the flavonoid retention in porcine ear skin after eight hours of permeation was below of limit of quantification for this compound. The polyphenols present in Vitis are capable of absorbing UV and visible light, justifying their potential as sunscreens for the development of a phytocosmetic. 相似文献
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In this work we show that homogeneous Neumann boundary conditions inhibit the Coleman-Weinberg mechanism for spontaneous symmetry breaking in the scalar electrodynamics if the length of the finite region is small enough (a = e2Mφ-1, where M, is the mass of the scalar field generated by the Coleman-Weinberg mechanism). 相似文献
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We clarify and develop the results of a previous paper on the birth of a closed universe of negative spatial curvature and multiply connected topology. In particular we discuss the initial instanton and the second topology change in more detail. This is followed by a short discussion of the results. 相似文献
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Railson C. S. da Luz Fábio P. Fagundes Rosangela de C. Balaban 《Chemical Papers》2017,71(12):2365-2373
This study aimed mainly to evaluate the influence of xanthan gum (XG) and carboxymethylcellulose (CMC) in the filtration process of water-based drilling fluids, considering the conformational changes suffered by the polyelectrolyte with the addition of salt (NaCl) in different concentrations (0.17, 0.34 and 0.51 M). It was also evaluated the behavior of the fluid by the addition of calcite (calcium carbonate, CaCO3). Sixteen drilling fluids were prepared with the same xanthan gum concentration (major application as thickener to transport the cuttings), but different salinities and having or not CMC and calcite at constant concentrations. This strategy was adopted to evaluate the real contribution of each additive in the control of filtration performance, frequently unclear in the papers. In general, the fluids prepared in all brines showed lower viscosities and higher filtrate loss compared to fluids of sweet water. This effect was more strong in fluids containing only XG. The addition of CMC enhanced the viscosity and reduced the filtrate loss. However, the best results were obtained when calcite was added. The results indicated that XG contribution as thickener is not enough to control efficiently the fluid filtration even in the presence of calcite. However, the addition of CMC and calcite to XG salt solution increased the viscosity and decreased significantly the filtrate loss. This result was attributed to synergistic interactions between XG, CMC and calcite. 相似文献