RESUMO
Endophytic fungi are fungi that colonize internal tissues of plants; several biologically active compounds have been isolated from these fungi. There are few studies of compounds isolated from endophytic fungi of Amazon plants. Thus, this study aimed the isolation and structural identification of ergosterol (1), ergosterol peroxide (2), mevalonolactone (3), cytochalasin B (4) and cytochalasin H (5) from Aspergillus sp. EJC 04, an endophytic fungus from Bauhinia guianensis. The cytochalasin B (4) and the diacetate derivative of cytochalasin B (4a) showed high lethality in the brine shrimp assay. This is the first occurrence of cytochalasins in Amazonian endophytic fungi from B. guianensis.
Assuntos
Artemia/efeitos dos fármacos , Aspergillus/química , Citocalasina B/toxicidade , Citocalasinas/toxicidade , Endófitos/química , Ergosterol/análogos & derivados , Fabaceae/microbiologia , Ácido Mevalônico/análogos & derivados , Acetilação , Animais , Argentina , Aspergillus/isolamento & purificação , Citocalasina B/química , Citocalasina B/isolamento & purificação , Citocalasinas/química , Citocalasinas/isolamento & purificação , Endófitos/isolamento & purificação , Ergosterol/química , Ergosterol/isolamento & purificação , Ergosterol/toxicidade , Dose Letal Mediana , Ácido Mevalônico/química , Ácido Mevalônico/isolamento & purificação , Ácido Mevalônico/toxicidade , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Espectrometria de Massas por Ionização por Electrospray , Relação Estrutura-AtividadeRESUMO
Bauhinia guianensis is a typical plant in the Amazon region belonging to the family Leguminosea, used by local populations for the treatment of infectious and renal diseases. Previous work on the plant B. guianensis led to the isolation of substances with anti-inflammatory and analgesic activities. Thus, compounds isolated from B. guianensis with antimicrobial activities had not been identified. Given that there is a possibility of biological activity reported for a given plant being found in the endophytic fungi, we decided to isolate endophytic fungi from B. guianensis and test their antimicrobial activities. The alkaloids known as fumigaclavine C and pseurotin A were isolated by column chromatography and identified by 1D and 2D NMR techniques and mass spectrometry. The alkaloids are first reported as broad-spectrum antibacterial agents with good activity.