Potential of natural products derived from plants in the treatment of candidiasis

Abstract

Candida is a yeast commonly found in the microbiota of the skin and mucosae of healthy individuals, whose pathogenicity can be activated by imbalance of host defense mechanisms, leading to pathologies called candidiasis. Although treatment with azole drugs is recommended, there are reports of Candida resistance to various antifungal agents. In addition, Candida has been associated with biofilms, a form of growth in which organisms adhere to surfaces beyond being involved by secreted exopolimeric substance themselves. Futhermore, there is a need for the search for new antifungals, especially the Copaifera plants due to their antimicrobial properties reported in folk medicine. Thus, the present work will aim to evaluate the antifungal potential of Copaifera against Candida species as well as evidence of the damage caused to fungal cells. In addition, in vivo tests will be performed for the demonstration of Copaifera cytotoxicity and pharmacodynamic evaluation. The strains tested will consist of Candida albicans ATCC 5314, Candida glabrata ATCC 2001, Candida parapsilosis ATCC 22019, Candida krusei ATCC 6258 e Candida tropicalis ATCC and the resin oils used will be of the following species: Copaifera paupera Dwyer, Copaifera reticulata Ducke, Copaifera langsdorffii Desfontaines, Copaifera trapeziofolia Hayne and Copaifera pubiflora Benth. In addition, the crude leaf extracts of C. paupera Dwyer, C. reticulata Ducke, Copaifera multijuga Hayne, C. pubiflora Benth, C. duckei Dwyer and C. langsdorffi Desfontaines will be used. The antifungal activity will be evaluated by the broth microdilution methodology with resazurin. The ability to prevent biofilms will be assessed by the 2-methoxy-4-nitro-5-sulfophenyl-5-phenylalanine carbonyl-2H-tetrazolium hydroxide-XTT) redution assay and the extent of damage to Candida cells will be evidenced by transmission electron microscopy. Copaifera toxicity will be assessed in vivo using the nematode Caenorhabditis elegans. The search for new compounds for the treatment of candidiasis reverts to benefits for the population besides establishing links between education and health. (AU)