Inhibitory effects of deoxynivalenol on pathogenesis of Candida albicans.

AIMS: To probe the inhibitory effects of deoxynivalenol (DON) on growth and biofilms of yeast and bacterial pathogens.

METHODS AND RESULTS: Crystal violet quantification, XTT reduction assay, confocal and scanning electron microscopic imaging, and yeast-to-hyphal inhibition assays were performed to demonstrate the inhibitory effects of DON. Our results show that DON and its modified form (3-acetyl-DON) caused dose-dependent inhibition of Candida albicans pathogenesis under in vitro conditions. DON significantly reduced C. albicans biofilm formation and metabolic activities, disrupted preformed biofilms without affecting planktonic cell growth, and inhibited hyphal protrusions in embedded colonies and free-living planktonic cells. We also show that DON and its derivatives function by interacting with lanosterol 14α-demethylase, thus mimicking the action mechanism of azole drugs.

CONCLUSIONS: Highlighting the importance of C. albicans biofilms and hyphal filamentations in inducing pathogen vigour, this study demonstrates the antihyphal and antibiofilm potential of DON against C. albicans.

SIGNIFICANCE AND IMPACT OF THE STUDY: Mycotoxin-producing moulds are able to dominate and control other microbes and insects in ecological niches. At times, they are known to eradicate biofilms of their intruders or symbiotic partners. In view of this coincident notion, the study proposes a role for mycotoxins as a biofilm inhibitor in ecological niches.