The increasing global demand for food and the necessity to ensure food security are significantly
challenged by fungal pathogens in crops. These pathogens not only diminish agricultural productivity but
also produce mycotoxins harmful to human and animal health. The dependence on synthetic fungicides has
resulted in environmental issues and the emergence of resistant strains, underscoring the need for alternative
solutions. In this context, the exploration of bioactive compounds from marine sources presents a promising
pathway for discovering new, sustainable, and effective natural antifungal agents.
This research involved bioprospecting marine samples from the Cies Islands, isolating
microorganisms, and generating a collection of organic extracts. The antifungal activity against the
phytopathogen Botrytis cinerea of both these extracts and the centrifuged broth was analyzed, which made
it possible to detect hydrophilic secondary metabolites not captured in their entirety in the extracts. The
results of the antifungal assays revealed that 64 out of 1726 extracts demonstrated significant antifungal
activity, and 24 out of 267 centrifuged broths showed similar potential. Chemical dereplication through
high-performance liquid chromatography (HPLC) identified 50 different compounds with a wide diversity
of secondary metabolites, including some known compounds such as ergosterol, maculosin, and FKI0076A. Finally molecular taxonomic identification of several active strains was carried out by DNA
sequencing. The results underscore the potential of marine microorganisms as promising reservoirs of
bioactive molecules. This research highlights the viability of natural marine compounds as antifungal agents
and reinforces the importance of exploring marine environments as a source of new natural antifungal
agents that could contribute significantly to global sustainability and food security.
