DEFAR - Artigos publicados em periódicos

URI permanente para esta coleçãohttp://www.hml.repositorio.ufop.br/handle/123456789/531

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2013 - 20153

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Autor: search.filters.author.Fonseca, Thaisa Helena SilvaTem arquivos: Sim

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    Insignificant level of in vitro cytotoxicity, anti‑rotavirus, antibacterial, and antifungal activities of N‑alkylmaleamic acids.
    (2013) Belinelo, Valdenir José; Campos, Michele Soares Tacchi; Antunes, Rafael Martins; Assenço, Regina Aparecida Gomes; Vieira Filho, Sidney Augusto; Lanna, Maria Célia da Silva; Marçal, Eduardo da Costa; Fonseca, Thaisa Helena Silva; Gomes, Maria Aparecida; Magalhães, José Carlos de
    By reacting maleic anhydride with amines, we synthesized the derivatives N‑ethyl, N‑(2‑ethylamine), N‑piperidinyl, N‑phenyl, and N‑phenylhydrazinyl maleamic acids. The purity of these products was initially verified by melting range and the presence of only one spot observed by thin layer chromatography. The chemical structures of the obtained N‑alkyl maleamic acids were confirmed through infrared (IR) and hydrogen and carbon nuclear magnetic resonance (1 H and 13C NMR) spectrometry. Due to the already proven pharmacological activity of maleimides, maleic anhydride and its N‑alkyl maleamic acids were subjected to in vitro assays to observe antiviral (SA‑11 rotavirus), antibacterial (Escherichia coli, Staphylococcus aureus, and Bacillus cereus), antifungal (Colletotrichum musae, Fusarium solani f. sp. phaseoli, Fusarium solani f. sp. piperis Alb., and Penicillium sp.), and antiprotozoal (Trichomonas vaginalis, Giardia lamblia, and Entamoeba histolytica) effects. To study the anti‑rotavirus properties, firstly the 3‑(4,5‑dimethylthiazol‑2‑yl)‑2‑5‑diphenyltetrazolium bromide (MTT) method was used to establish the median cytotoxicity concentration (CC50) of the compounds, using MA‑104 cell line. Under the experimental conditions used, cytotoxic, anti‑rotavirus, antibacterial, and antifungal properties were not observed for these compounds.
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    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 Aparecida
    Trichomoniasis, 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.
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    Salacia crassifolia (Celastraceae) : chemical constituents and antimicrobial activity.
    (2015) Rodrigues, Vanessa Gregório; Duarte, Lucienir Pains; Silva, Roqueline Rodrigues; Silva, Grácia Divina de Fátima; Simões, Maria O. Mercadante; Takahashi, Jacqueline Aparecida; Matildes, Bibiane Lindsay Guimarães; Fonseca, Thaisa Helena Silva; Gomes, Maria Aparecida; Vieira Filho, Sidney Augusto
    The phytochemical study of hexane extract from leaves of Salacia crassifolia resulted in the isolation of 3β-palmitoxy-urs-12-ene, 3-oxofriedelane, 3β-hydroxyfriedelane, 3-oxo-28-hydroxyfriedelane, 3-oxo-29-hydroxyfriedelane, 28,29-dihydroxyfriedelan-3-one, 3,4-seco-friedelan-3-oic acid, 3β-hydroxy-olean-9(11):12-diene and the mixture of α-amirin and β-amirin. β-sitosterol, the polymer gutta-percha, squalene and eicosanoic acid were also isolated. The chemical structures of these constituents were established by IR, 1H and 13C NMR spectral data. Crude extracts and the triterpenes were tested against Entamoeba histolytica, Giardia lamblia and Trichomonas vaginalis and no activity was observed under the in vitro assay conditions. The hexane, chloroform, ethyl acetate and ethanol crude extracts, and the constituent 3,4-seco-friedelan-3-oic acid and 28,29-dihydroxyfriedelan-3-one showed in vitro antimicrobial activity against Salmonella typhimurium, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus cereus, Listeria monocytogenes, Streptococcus sanguinis and Candida albicans.