Avaliação da viabilidade celular de Candida albicans frente à ação antifúngica do timol

• Ano de defesa: 2013
• Autor(a) principal: Vasconcelos, Laís César de
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal da Paraí­ba; BR; Odontologia; Programa de Pós Graduação em Odontologia; UFPB
• Palavras-chave em Português: Candida albicans; Timol; Viabilidade Celular; Thymol; Cell Viability; CNPQ::CIENCIAS DA SAUDE::ODONTOLOGIA
• Link de acesso: https://repositorio.ufpb.br/jspui/handle/tede/6658

Candida albicans is a yeast that lives harmlessly on various parts of the human body, including the oral cavity, however, under certain circumstances, may cause superficial infections of the mucous membranes, such as denture stomatitis, in which a biofilm of Candida is formed on the acrylic surface of dentures. Thymol is a phenolic terpene found in several plant species, which has antimicrobial activity against oral microorganisms such as Candida albicans, since it can significantly interfere with fungal biofilm formation and inhibit the metabolic activity of these microorganisms by direct action on cell membrane. This study evaluated through fluorescence technique the cell viability of Candida albicans biofilms under the antifungal activity of thymol. It was used strains of Candida albicans (ATCC® 11006 ). The minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of the antifungal drugs (miconazole and thymol) were determined by microdilution tests in Sabouraud dextrose broth. The drugs were prepared in dimethylsulfoxide (DMSO) and the inoculum was standardized to correspond to 0.5 of McFarland s scale (106 UFC/mL). Biofilms of Candida albicans were grown, from Sabouraud broth supplemented with 10% dextrose, on the surface of acrylic resin disks in parallel flow chambers and, after 12 hours of biofilm formation in a continuous flow system, it was exposure to the antifungal agents, being evaluated periods of 5, 15 and 30 minutes. For counting of colony-forming units, the fungal solution was sequentially diluted and plated on Sabouraud dextrose agar. Cell viability was quantified by fluorescence by mixing SYTO 9 and Propidium Iodide dyes. Data were evaluated by analysis of variance (ANOVA), Tukey's test and t-test at 5% probability. Biofilms treated with thymol showed, on the three incubation times evaluated, low percentage numbers of viable cells detected by fluorescence technique, and the average of the three incubation times between miconazole and thymol were not statistically different (p˃ 0.05), demonstrating that both drugs possess equivalent efficiency, taking into account their respective minimum fungicidal concentrations. It was possible to prove that both methodologies used to quantify fungal cells showed to be strongly correlated.