Antifungal activity of the honey flavonoid extract against Candida albicans

Candida albicans is the most prevalent dimorphic pathogen in humans. We investigated the potential protective effect of honey flavonoid extract (HFE) on Candida dimorphism induced by RPMI 1640 medium. Yeast to hyphal transition was dose dependently prevented when Candida cultures were treated with HFE for 6 h (germ-tube formation) and 18 h (hypha elongation). Since during hyphal growth remarkable amounts of reactive oxygen species (ROS) are generated, we investigated whether HFE affects the generation of ROS, the glutathione level and the activity of glutathione-dependent enzymes. Treatment of Candida cells with 48 μg/ml (MIC50) of HFE for 6 or 18 h inhibited the dimorphic conversion by supporting of the intracellular glutathione level. HFE exerts a dual protective effect inhibiting both ROS generation during germ-tube formation and γ-glutamyltranspeptidase activity, responsible for GSH degradation, during hypha elongation. These results show that HFE confers a significant protection against yeast to hyphal transition of C. albicans.