DEFAR - Artigos publicados em periódicos
URI permanente para esta coleçãohttp://www.hml.repositorio.ufop.br/handle/123456789/531
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Item Algistatic effect of a quinonamethide triterpene on Microcystis novacekii.(2013) Silva, Fernando César; Guedes, Fernanda Alves de Freitas; Franco, Maione Wittig; Barbosa, Francisco Antônio Rodrigues; Marra, Camila Antunes; Duarte, Lucienir Pains; Silva, Grácia Divina de Fátima; Vieira Filho, Sidney AugustoCyanobacteria proliferation represents a problem to water treatment for human consumption supply. Species of the genus Microcystis, commonly found in continental waters, can bloom and produce microcystine and other toxic compounds associated to human and animal poisoning, depending on the nutrient levels present in the water. The use of natural products to control cyanobacteria blooms is promising since they are less harmful to the environment than compounds obtained by organic syntheses. Triterpenes, which are associated with several biological activities, have been isolated from species of the genus Maytenus (Celastraceae), commonly found in Cerrado regions of Brazil. Tingenone is a pentacyclic triterpene that has cytotoxic properties and induces growth inhibition in some microorganisms. In this study, the effects of tingenone isolated from Maytenus gonoclada at distinct concentrations (e.g., 50, 150, 500, 1,500, and 4,500 μg L−1) on the growth rates of Microcystis novacekii was investigated. The algicide activity was verified using M. novacekii cultures growing in ASM1 culture medium at 23 °C and continuous illumination for 96 h. Growth inhibition was monitored by light microscopy and optical density (OD680 nm). The median effective concentration associated to the M. novacekii inhibition growth induced by tingenone was 12.2 μg L−1. The result indicates that tingenone has algicide effect and can be potentially applied in water management for public supply, replacing synthetic algicides.Item Chemical constituents from branches of Maytenus gonoclada (Celastraceae) and evaluation of antimicrobial activity.(2011) Silva, Fernando César; Duarte, Lucienir Pains; Silva, Grácia Divina de Fátima; Vieira Filho, Sidney Augusto; Lula, Ivana Silva; Takahashi, Jacqueline Aparecida; Sallum, William S. T.Seis triterpenos pentacíclicos isolados dos galhos de Maytenus gonoclada (Celastraceae), incluindo todos os dados de RMN do novo composto 3-oxo-12α,29-diidroxifriedelano são aqui relatados. A estereoquímica do novo friedelano foi estabelecida por dados de RMN bidimensional (HSQC, HMBC e NOESY), e sua massa molecular confirmada por espectrometria de massas (ESI). Testes de atividade antimicrobiana usando método de difusão em disco e de macrodiluição foram realizados contra as bactérias Escherichia coli, Citrobacter freundii e Bacillus cereus, e contra o fungo Candida albicans. O triterpeno 3-oxo-12a-hidroxifriedelano mostrou resultado positivo contra C. albicans.