| Grant number: | 18/02333-0 |
| Support type: | Regular Research Grants |
| Duration: | May 01, 2018 - April 30, 2020 |
| Field of knowledge: | Biological Sciences - Microbiology - Applied Microbiology |
| Principal researcher: | Regina Helena Pires |
| Grantee: | Regina Helena Pires |
| Home Institution: | Pró-Reitoria Adjunta de Pesquisa e Pós-Graduação. Universidade de Franca (UNIFRAN). Franca , SP, Brazil |
Abstract
Candida species are associated with surface or systemic infections that challenge public health in the face of emerging resistance to antifungal agents for clinical use. Among the potential sources for new antifungal agents, we highlight the antimicrobial properties of essential oils extracted from medicinal plants and plants of the Copaifera genus. In this context, this work will aim to evaluate the effects of antifungal activity of essential oils as well as leaf extracts against Candida species using in vitro and in vivo assays. The strains to be tested will include Candida albicans ATCC 5314, Candida glabrata ATCC 2001, Candida parapsilosis ATCC 22019, Candida krusei ATCC 6258, Candida tropicalis ATCC 13803, and Candida orthopsilosis ATCC 96141. The essential oils to be used will come from: litsia, cubiba, cypress, mint, rose, melaluca, petit grain, rosemary, birch, lemon grass, lemon, Piper aduncun (samples 1, 2 and 3), dried leaves and fresh leaves from ponkan tangerine, fresh cut leaves and peels from: ponkan tangerine, orange-pear of the river, bunch tangerine, Bahia tangerine and tangerine scones. Leaf extracts of Copaifera species - Copaifera paupera Dwyer and Copaifera reticulata Ducke - will also be tested. The antifungal activity will be evaluated both in vitro by the broth microdilution methodology with resazurin and in vivo by the use of the nematode Caenorhabditis elegans. Morphological changes in Candida cells after treatment with the plant products will be detected by flow cytometry. Damage to Candida cell wall, membrane and mitochondria will be visualized with the aid of electron transmission microscopy. The labeling with fluorochromes will allow both visualization of the damage to epifluorescence microscopy as well as quantification by molecular fluorescence spectrometry. In addition, the plant products effect on the biofilm formation and biofilm cell viability will be measured by the 2,3-Bis-(2-Methoxy-4-Nitro-5-Sulfophenyl)-2H-Tetrazolium-5-Carboxanilide (XTT) reduction assay. The elucidation of the anti-Candida mechanisms of the studied plant products will corroborate with the studies of ethnobotany that aims new antifungals for the treatment of candidiasis, a disease of relevance in the scope of public health. (AU)