Antifungal Activity of Medicinal Plants Against Oral Candida Albicans Isolates

In most countries of subtropical Africa, fungal infections represent an increasing problem. Candida albicans is the most common fungal pathogen and has developed an extensive array of putative virulent mechanisms that allows successful colonization and infection of the host under suitable predisposing conditions. Objectives: To investigate anti-Candida activity of crude acetone, hexane and water extracts of eight plant species, used as traditional medicine in southern Africa, against Candida albicans standard strain (ATCC 10231) and six clinical isolates. Methods: The disc diffusion and serial microplate dilution methods were used for antifungal testing. Minimal Inhibitory Concentration (MIC) values were regarded as the lowest concentrations of the extract that inhibited the growth of C. albicans standard strain (ATCC 10231) and clinical isolates. Results: MIC's below 1 mg/ml was observed for the acetone and water extracts of Bidens pilosa (whole plant), acetone extracts of Harpephyllum caffrum (leaves), Ptaeroxylon obliquum (leaves), Rapanea melanophloeos (leaves) and acetone and water extracts of Sclerocarya birrea (stem bark). Bioautography confirmed the presence of compounds with antifungal activity in S. birrea and P. obliquum. Conclusions: The results implicate that the extracts contain compounds with therapeutic potential against C. albicans. These compounds are currently being isolated.