Constituintes químicos e avaliação preliminar in vivo da atividade antimalárica de Ouratea nitida Aubl (Ochnaceae) / Chemical constituents and in vivo preliminary evaluation of antimalarial activity of Ouratea nitida Aubl. (Ochnaceae)

O presente trabalho descreve o isolamento de triterpenos (ácido 3,4-seco-friedelan-3-óico, friedelina e b-amirina) e outros compostos (éster etílico do ácido p-hidroxibenzóico e tetracosano), bem como a avaliação preliminar in vivo da atividade antimalárica de extratos das folhas de Ouratea nitida Aubl. Análise qualitativa através de CG-EM de uma fração apolar do extrato em hexano também foi efetuada. Ésteres metílicos e etílicos dos ácidos laúrico, mirístico, palmítico, esteárico e oléico, metílicos dos ácidos pentadecanóico, heptadecanóico, araquidônico, behênico e lignocérico e o etílico do ácido linoléico foram os componentes majoritários; enquanto que o estearato de n-butila, o tetracosano e a 6,10,14-trimetil-2-pentadecanona foram os minoritários. Os compostos isolados foram identificados com base na análise dos dados espectrais (IV, EM e RMN, incluindo DEPT) e estão sendo descritos pela primeira vez nesta espécie.

This work describes the isolation of triterpenes (3,4-seco-friedelan-3-oic acid, friedelin, and b-amyrin) and other compounds (p-hydroxybenzoic acid ethyl ester and tetracosane) as well as a preliminary evaluation of in vivo antimalarial activity of the extracts from the leaves of Ouratea nitida Aubl. Qualitative analysis by GC-MS of an apolar fraction from the hexane extract was also carried out. Methyl and ethyl esters of lauric, myristic, palmitic, stearic and oleic acids, methyl ester of pentadecanoic, heptadecanoic, arachidonic, beenic and lignoceric acids, and ethyl ester of linoleic acid were found to be the main constituents while n-butyl stearate, tetracosane and 6,10,14-trimetthyl-2-pentadecanone were the minor. All isolated compounds were identified on basis of the spectral data (IR, MS and NMR, including DEPT) and are being described for the first time in this specie.

Seasonal variation in the essential oil of Pilocarpus microphyllus Stapf

The essential oils of the leaves and fine stems of Pilocarpus microphyllus, collected on iron mineralized soil of the Serra de Carajás, Southeast of Pará State, Brazil, during the rainy and dry seasons, were obtained by hydrodistillation and analyzed by GC-MS. The main identified compounds were 2-tridecanone, beta-caryophyllene, 2-pentadecanone, caryophyllene oxide and germacrene D. Their percentage contents varied with the season, the greater values having been detected mainly in the rainy season. For 2-tridecanone and beta-caryophyllene the higher values were observed in the fine stem oils for the former, and in the leaf oils for the latter. For 2-pentadecanone, caryophyllene oxide and germacrene D they were also in the leaf oils. In general, the leaf oils were very distinguishable from those of fine stem oils, even in the same specimen