Chemical study and evaluation of antimicrobial activity of endophytic fungi associated with Paepalanthus chiquitensis (Eriocaulaceae) and effects of chemical epigenetic modulators in the cultivation of Pochonia chlamydosporia

Author(s)

Felipe Hilário

• Document type: Master's Dissertation
• Press: Araraquara. 2016-03-23.
• Institution: Universidade Estadual Paulista (Unesp). Faculdade de Ciências Farmacêuticas. Araraquara
• Defense date: 2016-02-22
• Advisor: Lourdes Campaner dos Santos

Abstract

This work presents the results of the research of active secondary metabolites produced by endophytic fungi associated with the aerial parts (capitulae, scapes and leaves) of Paepalanthus chiquitensis (Eriocaulaceae). Among the 25 species of fungi isolated from the specie of Eriocaulaceae, the Fusarium sp. was the fungus that showed the best biological activity against the strains of Gram-negative bacteria Escherichia coli and Salmonella setubal, the Gram-positive bacterium Staphylococus aureus and Candida albicans yeast resistant to fluconazole. The Fusarium sp also displayed bactericidal and fungicidal effects. The research also presents the chemical studies of the fungus Bipolares sp., isolated from the leaves of P. chiquitensis which was selected due to its chemical profile. The large scale cultivation of both fungi afforded the respective ethyl acetate extracts which were purified by preparative chromatography methods. The chemical structures were elucidated by spectrometric and spectroscopic methods (MS, IR, UV, mono- and bidimensional NMR affording the following substances from the Fusarium sp.: 5-(but-3-en-1-yl)-N4-methylpyridine-3,4-diamine (S1), fusaric acid (S2), 2-(1H-indol-6-yl)-acid (S3), 5-Butil-2-pyridinecarboxamide (S4) and the sesterterpene fusaproliferin (S5), while for the Bipolaris sp.: Acetic acid, (2-acetyl-3,5-dihydroxyphenyl)-, ethyl ester (B4) and a new alkaloid (B1). Herein, we also showed the study of the effects of epigenetic modifiers and metal ions in metabolic diversity from the fungus Pochonia chlamydosporia (ATCC). The presence of anacardic acid in the liquid medium afforded 2.6 times more ethyl acetate extract compared with the PDB (Potato Dextrose Broth) control. Besides, the analysis by analytical HPLC (High Performance Liquid Chromatography) identified the radicicol as the major compound present in EtOAc extracts and showed that when anacardic acid (AA) is added to the liquid medium, there is a production of 4.6 times more of the radicicol than the PDB control. This fungus was cultivated in large scale in PDB + Mg2+, yielding four compounds absent in thePDB control: pochonins B, E and L and the myxostiol compounds (P1-P4), respectively. (AU)

• FAPESP's process: 13/12564-6 - Chemical study and evaluation of antimicrobial activity of endophytic fungi associated with Paepalanthus chiquitensis (Eriocaulaceae) and effects of chemical epigenetic modulators in the cultivation of Pochonia chlamydosporia
• Grantee: Felipe Hilário
• Support type: Scholarships in Brazil - Master