Ação de chalconas sobre a formação de biofilme de candida albicans isoladas de cavidade bucal

Abstract

The incidence of fungal infections has increased significantly in recent years. Candida albicans yeast is responsible for most of these infections. It fungus is an opportunistic dimorphic which presents itself in the form of yeast in the state saprobic associated with asymptomatic colonization, or as a form of pseudo-filamentous hyphae and true hyphae in infectious processes. The set of specific virulence factors, such as adhesins, production of proteases and phospholipases, besides the formation of microbial communities called biofilms, facilitate tissue penetration and confer a higher pathogenicity to these yeasts. Although there is considerable amount of available antifungal agents, many of them have similar modes of action, a fact which contributes to the increasing incidence of resistance among pathogenic fungi. Therefore, there is a growing need for new therapies. In this context, the control of the expression of virulence factors of C. albicans is found as an interesting complementary approach to the antifungal armamentarium available and investigation of compounds derived from the basic structure of chalconas have shown promising results in inhibition of microorganisms. In this work we studied virulence factors of 32 samples C. albicans isolated from the oral cavity, such as morphotyping, tubotipagem, enzimotipagem and biofilm formation by typing addition to killer toxins. The synthesized compounds were evaluated for toxicity testing of brine shrimp lethality, antifungal activity and impact of subinibitory concentrations in biofilm formation by these micro-organisms. The results showed that isolates of variably expressed virulence factors C. albicans, all yeasts were biofilm formers and that there was no correlation between this property and the concomitant expression of other virulence factors. The chalconas presented with low toxicity against A. salina, with little antifungal activity and a significant inhibitory effect of biofilm formation by C. albicans.