Anti-Candida Activity in Vitro of Tagetes patula L. (Asteraceae) Extracts

The phytochemical investigation of different parts of Tagetes patula L. (Asteraceae) has resulted in the isolation of several chemical constituents in many different classes of secondary metabolites, such as thiophenes, benzofurans, carotenoids and principally flavonoids. The main agent of candidiasis is Candida albicans, constituting the agent of the majority of clinical cases, however, can be found other vectors, such as Candida tropicalis, Candida parapsilosis, Candida krusei, Candida glabrata, among others. The aim of this study was the search for a product of natural origin that can be used in effective control of these microorganisms. T. patula extracts were tested against strains of C. glabrata (ATCC 90030), C. krusei (ATCC 6258), C. parapsilosis (ATCC 22019) and C. tropicalis (ATCC 750). The minimum inhibitory concentrations (MIC) were determined by microdilution for extracts obtained with different solvents by percolation of the aerial parts (PA) and flowers (FL) of T. patula (initial concentration 1250 µg/mL). The results revealed that, with the exception of the excellent activity of ethanolic (EtOH) and methanolic (MeOH) extracts against C. glabrata (MIC_PAEtOH= 78.12 µg/mL, MIC_FLEtOH= 39.06 µg/mL, MIC_PAMeOH= 78.12 µg/mL and MIC_FLMeOH= 51.08 µg/mL), all samples were ineffective against other three strains of Candida. These results suggest a good action against the yeast strain with concentrations below 100.0 µg/mL, allowing future studies on the synergistic action of extracts of T. patula with commercially used antifungal agents.

Support: FAPESP