Avaliação da atividade antifúngica de ésteres benzoicos estruturalmente relacionados frente a espécies de Candida

Abstract

The benzoic derivatives have been related to antioxidant activity, anti-inflammatory, cytotoxic (cancer cell), antiviral, antibacterial and antifungal, an growing interest in the scientific field. In the present study, it was investigated the antifungal activity of a collection of benzoic acids esters derivatives, against the pathogenic species of Candida genus; causing the broad espectrum of fungal infections known as candidiasis. It was used the esterification catalyzed by acid to obtain the evaluated esters and the antifungal tests were performed with the microdilution broth method. The main objective of this study was to evaluate the influence of the presence and position of the various substituents of the aromatic ring of the esters, including: -OH, -CH3, -Ar, NO2, in the biological activity. The results were satisfactory. The bioactive substances showed good to moderate the bioactivity; the best MIC vary between 256μg / ml and 64μg / ml, this last one was presented by p-hydroxybenzoate methyl ester, against C. krusei and C. parapsilosis species. Some comments were made about the influence of substituents in this bioactivity: the methyl group in para position of the ring contributed to the inactivity of the compounds in question; the hydroxyl group in the same position improved bioactivity in some cases, being important for interaction with components of the fungal membrane through hydrogen bonding; the nitro group, through its reducing ability, may have been relevant to the bioactivity of the respective ester and the presence of a second aromatic ring in the ortho or para position, guarantee the bioactivity of the biphenyl substances. The results presented in the work presented relevance to the search of a compound with improved biological profile which can be used in the development of new antifungal drugs.