Allyl isothiocyanate suppresses the growth and pathogenicity of Candida albicans.

Candida albicans is a fungus that is predominantly detected in the oral cavity and causes opportunistic infections. Among the elderly, a decline in the host's resistance to pathogens due to immunosenescence makes them more susceptible to oral candidiasis, which eventually may progress to systemic candidiasis. Allyl isothiocyanate (AITC) is a component found in Brassicaceae plants (such as wasabi), which possesses strong antibacterial properties and is used as a food preservative. In this study, the effects of AITC on C. albicans were investigated though: (1) inhibition of growth and biofilm formation, (2) inhibition of adhesion to denture base resin, (3) inhibition of dimorphic transformation that exacerbates pathogenicity, and (4) inhibition of the production of secretory aspartic protease and lipase. Taken together, this suggests that AITC suppresses the growth and pathogenicity of this fungus. Further investigation of the mechanism revealed a decrease in hyphae-specific gene expression in the intracellular signaling MAP kinase cascade and cAMP pathway, as well as the induction of oxidative stress and a tendency toward apoptosis within C. albicans cells. Based on these findings, we propose that AITC may be beneficial for the prevention and suppression of oral candidiasis and has the potential for clinical application aimed at improving oral care and quality of life.