SUNFLOWER HULLS POLYPHENOLIC EXTRACT EXHIBITS ANTIFUNGAL PROPERTIES AGAINST C. albicans

DEL RÍO, MARIANELA; PASQUAL, NAHUEL; RODRÍGUEZ, GUADALUPE; RADICIONI, MELISA BELÉN; MARTÍNEZ, GUADALUPE; REGENTE, MARIANA

Congreso; REUNIÓN ANUAL DE SOCIEDADES DE BIOCIENCIAS 2022; 2022

Candida albicans is an opportunistic fungus causing superficial and systemic infections. The search for safe and efficient antifungal compounds is a challenge for researchers. Sunflower hulls (SH) is an agroindustrial by-product rich in phenolic compounds with bioactive properties potentially applicable as natural therapeutic agents. The objective of this work was to explore the antifungal activity of polyphenol extract from SH on C. albicans. Phenolic extracts (EPC) were prepared by maceration of SH in 80% ethanol and total polyphenols were quantified with the Folin-Ciocalteu method. Fungal growth inhibition assays were performed in liquid medium in the presence and absence of EPC and OD reading at 630 nm was determined. EPC 0.25 mg/ml and 0.5 mg/ml showed 0-3.5% and 51-83% inhibition of yeast growth, respectively. Subsequently, cell viability was studied by colony count in solid medium, and 25.8-38% and 78-80% death was recorded in the yeasts treated with EPC 0.25 mg/ml and 0,5 mg/ml, respectively. In addition, the incorporation of Evans blue in the yeasts treated with EPC 0,5 mg/ml was visualized by microscopy analysis, indicating changes in the permeability of the plasma membrane. Through cell wall (congo red) and plasma membrane (SDS) disruptive agent assays, it was shown that EPC 0.25 mg/ml strongly inhibits fungal growth in the presence of SDS, demonstrating that the plasma membrane is its target of action. On the other hand, the effect of EPC on morphological switching, a virulence factors of C. albicans, was studied. The incubation of yeasts under conditions of pseudohyphae induction in the presence of EPC showed an inhibition of dimorphism between 52.8% and 100%, for each dose respectively, keeping the yeasts in their blastospore form. Thus, our results highlight the polyphenolic extract from sunflower hulls as a potential tool for the treatment of fungal diseases.