Atividade antifúngica de extratos de plantas do semiárido paraibano frente a leveduras do gênero candida.

Abstract

The genus Candida is composed of opportunistic pathogens that live in the normal microbiota of humans and animals. Some factors may contribute to the rupture of the symbiosis relationship; this can lead to an increase in multiplication and invasion of the tissue causing infection in the host, thanks to immunological, chemical, and mechanical changes. The emergence and spread of microorganisms resistant to antifungal drugs, which are available on the market stimulates researches for new sources of substances that present efficient antimicrobial activities. Analysis of natural substances is essential for the discovery of new methods for the development of antimicrobial agents. This study aims to evaluate the antifungal activity of the extract of Hibiscus rosa-sinensis Linn, Mimosa tenuiflora, and Anacardium occidentale on yeasts of the genus Candida including C. albicans, C. parapsilosis, C. tropicalis, C. famata, C. metapsilosis, and C. orthopsilosis. The Foundation known in Brazil as the Oswaldo Cruz Foundation (in Brazilian acronym: Fiocruz) had donated standard stains used in the test which were developed by inoculum from recent cultures of the microorganisms. Through the hydroalcoholic macerate of the plants, the crude extract was obtained which was tested in the cultures. The research of extracts of Mimosa tenuiflora and Anacardium occidentale presented to be active against the tested species. The extract of Mimosa tenuiflora presented a better inhibitory effect against the C. famata strain, and Minimal Inhibitory Concentration (MIC) at the dilution of 25%, while the extract of Anacardium occidentale presented the lowest value of MIC against C. albicans strain at the dilution of 12.5. It is indicated the plants with antifungal potential, for further studies that it may identifies one or more active fractions to obtain viable natural pharmaceutical forms against the mentioned Candida species.