Estudo químico e biológico dos ramos de espécies do gênero vismia vand. (hypericaceae)

Abstract

Vismia species (Hypericaceae) are often pioneers in the successional processes of secondary forests, dominating extensive areas, called “vismiais”. In studies with species of this genus are related the activities: antioxidant, antibacterian, cytotoxic, leishmanicid, antimalaric, and others. Our study proposes amplified the chemical and biological knowledge of branches of V. japurensis Reichardt. V. cauliflora A. C. Sm. and V. sandwithii Ewan. Three sampling of V. japurensis, one of V. cauliflora, and one of V. cauliflora has performed. The materials has dried, milled and extracted with hexane, methanol and water. The hexanic extracts of three species has analysed using chromatographic technics (thin layer chromatography and nuclear magnetic resonance of 1H). The branches of the first sampling of V. japurensis and V. sandwithii has submitted to many chromatographic fractions. The structural determination of substances has performed using spectroscopic methods (1H NMR and 13C, including bidimensionals technics: HSQC, HMBC, COSY and NOESY) and mass spectrometry, besides of comparison with literature. In the hexanic extracts of V. japurensis has isolated one triterpene (friedelin) and three anthraquinones (madagascin, physcion and vismiaquinone). In the hexanic extracts of V. sandwithii has isolated one triterpene (friedelanol). The hexanic and methanolic extracts of the first sample of branches of V. japurensis has tested for activity antioxidant, but no have activity. The toxicity activity against Artemia salina has performed and the V. japurensis extracts presented toxicity in concentration 1000 g/mL, with mortality of 96% of larvae to hexanic extract of the first sampling and the three sampling presented mortality of 63% (hexanic) and 83% (methanolic). The antiangiogenic activity has tested with hexanic extracts of the first sampling and presented activity in 100, 500 and 1000 g/mL concentrations, with inhibition percentuale of new blood vessels of approximately 60, 80 and 90%, respectively. For third sampling of V. japurensis, has tested in same concentrations, presented the respectively inhibition values 60, 80 and 97%. The hexanic extracts from V. japurensis and V. sandwithii has tested for microdilution method and has considered active with minimal inhibitory concentration (MIC) of 500 g/mL against Klebsiella pneumoniae, Citrobacter freundii, Acinetobacter baumanii, Staphylococcus epidermidis, Edwardsiella tarda e Pseudomonas aeruginosa. This is the first study using V. sandwithii branches, being this the first report of triterpene (friedelanol), and the first time the biological activity is being described for this species. For V. japurensis species, this is the first report of chemical and biological study with your branches.