Prospecção química dos metabólitos produzidos pelos fungos endofíticos associados aos capítulos de Paepalanthus planifolius e estudo fitoquímico dos capítulos de Paepalanthus planifolius (Eriocaulaceae)

• Ano de defesa: 2015
• Autor(a) principal: Amorim, Marcelo Rodrigues de [UNESP]
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Estadual Paulista (Unesp)
• Palavras-chave em Português: Fungos endofíticos; Metabólitos; Espectrometria de massa; Cromatografia líquida de alta eficiência; Espinhaço, Serra do (MG e BA)
• Link de acesso: http://hdl.handle.net/11449/143003

Eriocaulaceae stand out as one of the most representative families of the rocky fields of the Espinhaço - MG, not only for the great richness of species, but also the high number of endemic taxa of this geological formation. The capitula of Paepalanthus planifolius, one of the most representative genera of the family, have been isolated from the ethanol extract and dichloromethane the naphytopyranones, substances with proven biological activity as antiradical, anti-ulcer and mutagenic. Despite the studies performed to date with Eriocaulaceae species, it is important to note that there is still a wide variety of substances were not yet isolated and identified and that have not been evaluated for various biological activities So in this paper we describe the isolation, purification, identification of substances and preservation of endophytes associated with the P. planifolius specie. The chemical screening was performed by high-performance liquid chromatography coupled with a photodiode array detector HPLC-DAD, comparative thin layer chromatography (TLC) and antiradical assay conducted with extracts partitioned with ethyl acetate (EtOAc) of the capitula of the isolated endophytic P. planifolius, on a reduced scaled. The chemical profile of this preliminary screening allowed us to select the extract produced by the endophytic fungus identified as Anthostomella brabeji for the study on a large scale in the PDB culture media. The fractionation strategy by HPLC-DAD in semi-preparative scale EtOAc extract endophyte A. brabeji allowed to isolate and identify four secondary metabolites [(6-hydroxy-2,2-dimethyl-5,6,7,8-tetrahydro-7,8-epoxychroman-4-one (Ab1), Siccayne (Ab2), Eutypinol (Ab3) e 6,7,8-hydroxy-2,2-dimethyl-5,6,7,8-tetrahydro-chroman-4-one (Ab4)] which were identified by NMR techniques mono- and bi-dimensional and mass spectrometry, and the Ab4 substance is being described at the first time in...