Banca de QUALIFICAÇÃO: HECTOR MAURICIO CASANOVA NAVARRO

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
DISCENTE : HECTOR MAURICIO CASANOVA NAVARRO
DATA : 31/03/2023
HORA: 08:00
LOCAL: Virtual
TÍTULO:

Secondary metabolites of the marine fungus Epicoccum chloridis FMPV 05: biological activity and potential modes of action against emerging pathogens

PALAVRAS-CHAVES:

Antimicrobial activity, polyketides, chemodiversity, molecular taxonomy, Didymellaceae

PÁGINAS: 1
RESUMO:

The global impact of antimicrobial resistance (AMR) is uncontrolled, accounting for around 3 million
deaths per year from fungal (IF) and bacterial infections and an excessive number of more than 600
million records annually. The search for new antimicrobial compounds and the elucidation of their
modes of action has become a global public health priority. Fungi from the marine environment in recent decades have been the focus of attention in bioprospecting new mycocompounds capable of meeting the growing need for antimicrobials. Consider marine fungi capable of producing an arsenal of compounds favored by the genetic tools acquired in their evolutionary processes and the extreme abiotic and biotic factors to which they are subjected in marine ecosystems. Exploring the production of secondary metabolites (fingerprint) through GC-MS and HPLC-DAD techniques, together with the evaluation of biological activities, as well as determination and control of virulence factors and possible mechanisms of action of the mycocompounds produced by the marine fungus Epicoccum chloridis FMPV 05 against the pathogens Candida albicans, Cryptococcus neoformans, and Staphylococcus aureus was the focus of study in this work. The hexane extract (HPLC-DAD) analysis was partitioned to obtain five fractions (Fr-1 - Fr-5) of which Fr-1 and Fr-2 showed antimicrobial activity. They were subjected to analysis by GC-MS, resulting in SI > of 98 Ethanol, 2-butoxy (1) and Heneicosane (2) and others mycocompounds. These Fr-1 and Fr-2 also showed significant activities in controlling virulence factors for pathogenic fungi, such as antibiofilm and inhibition of pseudohyphae production. Other activities showed interesting results with low levels of hemolytic activity, suggesting low toxicity against human erythrocytes. The potential modes of action were related to mechanisms in the cell wall or membrane of evaluated fungi through exogenous ergosterol binding assays and the sorbitol assay. It reinforces the potential of fungi from the marine environment in the production of mycocompounds that can be candidates as new antimicrobials or supporting existing ones, as well as possible controllers of several virulence factors that can mitigate the impact of fungal infections.

MEMBROS DA BANCA:
Presidente - 2024367 - MELISSA FONTES LANDELL
Interno(a) - 1916144 - GILBERTO COSTA JUSTINO
Externo(a) ao Programa - 1369387 - JOAO XAVIER DE ARAUJO JUNIOR
Externo(a) à Instituição - ALEXANDRE JOSÉ MACEDO - UFRGS
Externo(a) à Instituição - DENISE BRENTAN DA SILVA - UFMS