Antifungal and anti-biofilm effects of 6-shogaol against Candida auris.

This study aimed to assess the antifungal and anti-biofilm effects of 6-shogaol against Candida auris using in vitro phenotypic and genotypic analyses. Our results showed that 6-shogaol exhibited antifungal as well as anti-biofilm activity by inhibiting biofilm formation and eradicating the preformed biofilms of C. auris. The rate and extent of antifungal activity were further confirmed by a time-kill assay. The XTT reduction assay confirmed that 6-shogaol decreased cellular metabolic activity in the biofilm. The effect of 6-shogaol on established C. auris biofilms was visualized by confocal laser scanning microscopy. Also, this study demonstrated that 6-shogaol reduced the levels of aspartyl proteinases and downregulated the expression of the efflux pump-related CDR1 gene in C. auris. The data indicated that 6-shogaol extracted from ginger had antifungal and anti-biofilm effects on C. auris. This study demonstrated the value of the plant-derived 6-shogaol as a promising and potent bioactive compound. The mode of action of this compound against C. auris biofilm was also proposed.