RESUMO
A new phenolic derivative, 2,8-dihydroxy-7H-furo[2,3-f]chromen-7-one (1), together with isoquercitrin (2), was isolated from the aerial parts of Tibouchina paratropica. Compound structures were elucidated by spectroscopic methods. Both compounds show antimicrobial activity towards a panel of bacterial and fungal pathogens, and compound 1 displayed potent anti-parasitic activity against Leishmania donovani (IC50 = 0.809 µg/mL). In addition, an 85% reduction in the secretion of the pro-inflammatory cytokine IL-6 was recorded when macrophages challenged with lipopolysaccharide were exposed to compound 1, but no effect on the anti-inflammatory IL-10 was observed. Compound 2 showed neither anti-parasitic nor anti-inflammatory properties. In addition, no cytotoxic activities were observed against the human-derived macrophage THP-1 cells.
Assuntos
Antiprotozoários/farmacologia , Furocumarinas/isolamento & purificação , Furocumarinas/farmacologia , Leishmania donovani/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Melastomataceae/química , Extratos Vegetais/química , Anti-Infecciosos/farmacologia , Anti-Inflamatórios/farmacologia , Argentina , Bactérias/efeitos dos fármacos , Linhagem Celular , Fungos/efeitos dos fármacos , Furocumarinas/química , Humanos , Interleucina-10/imunologia , Interleucina-6/imunologia , Lipopolissacarídeos , Macrófagos/imunologia , Testes de Sensibilidade Microbiana , Fenóis/farmacologia , Componentes Aéreos da Planta/química , Quercetina/análogos & derivados , Quercetina/isolamento & purificação , Quercetina/farmacologiaRESUMO
Six compounds from the aerial parts of the Argentinean plant Hymenoxys robusta (Rusby) Parker were isolated and their structures elucidated using extensive spectroscopic analyses. These compounds comprise two inositol derivatives and four 3,4-seco-pseudoguaianolides, including vermeerin. Bioactivity assays of these compounds against bacterial and fungal pathogens showed that only vermeerin possessed antimicrobial activity specific against Staphylococcus aureus, and showed no toxicity when exposed to human-derived macrophages.