Avaliação da atividade antibiótica de metabólitos secundários de fungos endofíticos da Euphorbia tirucalli.

Abstract

The world is currently experiencing a crisis of antibiotic resistance. Many of the drugs used to treat infections were discovered in the 1950s and are no longer effective against superbugs. Investment in the search for new antimicrobials is therefore essential. The endophytic fungi of Euphorbia tirucalli are promising sources to produce bioactive substances and, consequently, possible new drugs that are effective against resistant strains of bacteria. The aim of this study was therefore to produce and evaluate the antibiotic activity of the secondary metabolites of the endophytes isolated from Aveloz on Escherichia coli bacteria. The antibacterial activity was measured using a broth dilution test in a 96-well microplate. The data was read with the addition of 0.01% resazurin and analyzed using ImageJ software, using the ReadPlate3.0 plugin. The sample data was tested for normality and significance and 28.3% of the fungi tested showed antimicrobial activity against E. coli. Of these, 18.5% were more potent than the antibiotic control using 100 μg of amoxicillin and 5.43% were more potent than the control using 1000 μg of amoxicillin. The fungus Et068 stood out, showing greater potential among the fungi tested. Thus, the secondary metabolites of endophytic fungi isolated from E. tirucalli are promising biomolecules to produce new spectrum antibiotics.