Synthesis, antifungal activity of caffeic acid derivative esters, and their synergism with fluconazole and nystatin against Candida spp.

We tested the antifungal potential of caffeic acid and 8 of its derivative esters against Candidaalbicans ATCC 90028 and 9 clinical isolatesand carried out a synergism assay with fluconazole and nystatin. Propyl caffeate (C3) showed the best antifungal activity against the tested strains. When in combination, C3 markedly reduced the MIC of fluconazole and nystatin with synergistic effect up to 64-fold. Finally, C3 showed a high IC50 value and selective indexagainst oral keratinocytes, demonstrating low toxicity against this cell type and selectivity for yeast cells. Further research should confirm its antifungal potential for development of combined therapy to treat C. albicans infections.