Avaliação da atividade antifúngica do extrato metanólico de Psidium guineense (Myrtacea) contra cepas do gênero candida.

Abstract

Candidiasis is the most common fungal infection of the oral cavity, and its etiological factor is the proliferation and growth of microorganisms of the genus Candida. Candida fungi make up the diverse microbiota of the oral cavity, living in a harmless commensal relationship with the host and being able to colonize different habitats such as mucosa and skin. Several antifungal drugs have been used for the treatment of candidiasis, such as azole antifungals (ketoconazole, fluconazole) and polyene antifungals (nystatin, amphotericin B). Therefore, the use of medicinal plants presents itself as a viable and promising alternative for the discovery of new phytopharmaceutical agents with great biological potential. Based on literature studies that show the physical-chemical and ethnopharmacological characteristics of medicinal plant species, this research aimed to evaluate the antifungal activity of the methanolic extract of Psidium guineense (Myrtaceae). The study was performed through in vitro assays where the methanolic extract of Psidium guineense was used as test substance against the fungal species Candida albicans, Candida tropicalis and Candida krusei previously identified and maintained in culture media of Sabouraud dextrose agar (SDA) and Sabouraud dextrose broth (SSD). In addition, nystatin was used as the standard antifungal for the positive control. The microdilution broth technique was used to determine the Minimum Inhibitory Concentration (MIC) of Psidium guineense methanolic extract. Thus, it was obtained as a result the MIC value higher than 1024 μg/mL, indicating that the methanolic extract of Psidium guineense had no antifungal activity by the methodology used against the strains tested.