Estudo químico dos fungos endofíticos Phomopsis sp., Guignardia sp., Aspergillus niger e Aspergillus sp., associados à espécie vegetal Hancornia speciosa (Apocinaceae)

• Ano de defesa: 2011
• Autor(a) principal: Santos, Mário Ferreira Conceição
• Orientador(a): Silva, Geraldo Humberto
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Sergipe
• Programa de Pós-Graduação: Pós-Graduação em Química
• País: BR
• Palavras-chave em Português: Fungos endofíticos; Hamcornia speciosa; Metabolitos secundários bioativos
• Palavras-chave em Inglês: Endophytic fungi; Hancornia speciosa; Secundary metabolites
• Área do conhecimento CNPq: CNPQ::CIENCIAS EXATAS E DA TERRA::QUIMICA
• Link de acesso: https://ri.ufs.br/handle/riufs/6151

This work describes the isolation of endophytic fungi from plant species Hancornia speciosa and led to the isolation of 14 pure strains. Of which 4 were selected for the chemical study. The chemical study allowed identied 12 substances isolated from fungi Phomopsis sp., Guignardia sp., Aspergillus niger e Aspergillus sp., grown in different culture medium. The crude extracts of fungus Phomopsis sp., grown in PDB medium led to isolation of five compounds, 5- methylmelein, nectriapyrone, succnic acid, 5-hydroxylmethylmelein and a diketopiperazine. Already when the same fungus was grown in ME medium, led to isolation of two compounds, tyrosol and tryptofol. The crude extract of Guignardia sp grown in ME medium led to isolation of compound salicylic acid, which has a plant for ecological importance.The crude extract of Aspergillus niger, grown in PDB medium led to isolation of compounds pyrophen and nigragillin. Already when the same fungus was grown in ME medium, led to isolation of compound itaconic acid. And of crude extract of Aspergillus sp., grown in ME medium was identification of their major compound kojic acid, which was quantified by HPLC in the crude extract (0.7 mg/g of crude extract). O crude extract was tested for its antioxidant activity with DPPH, NO. and H2O2, and exhibited significantly potent inhibition of NO (IC50 de 150 μg/mL) production, showed taht this fungi it owns big biotchenology potential. The structures of these substances were established by spectroscopic methods, including the application of bidimensional NMR techniques, mass spectrum and comparison with published data.