Growth inhibition effect of Brazilian Cerrado plant extracts on Candida species

Abstract

Ethanol extracts from leaves of Annona crassiflora and A. coriacea, and the fruits of Solanum lycocarpum and S. grandiflorum were investigated against 52 strains of Candida albicans, four strains of C. tropicalis and three strains of C. krusei isolated from human immunodeficiency virus-infected individuals with oropharyngeal candidosis, using the agar dilution method. Among the extracts tested, leaves of A. crassiflora was active against all the microorganisms and showed the greatest antifungal activity based on the MIC values. It was observed that 57 strains (96%) were inhibited by the extract from A. crassiflora at a concentration of 64 μg/ml, whereas against 18 strains (30%), it exhibited MIC values as low as 0.5 μg/ml against 106 UFC/ml organisms. Candida albicans CBS 562, a reference strain used as a control, showed a similar inhibition pattern. The activities of fluconazole, itraconazole, and ketoconazole were also evaluated and afforded MIC values ≥ 32 μg/ml (19.5% of all strains), ≥ 64 μg/ml (13.6%), and ≥ 128 μg/ml (32.2%), respectively.