Antifungal activity and mechanism of citral, limonene and eugenol against Zygosaccharomyces rouxii

The aim of this study was to investigate the antifungal activity and mechanisms of citral, limonene and eugenol against Zygosaccharomyces rouxii . All the three essential oil ingredients presented strong antifungal activities against Z. rouxii . Minimum inhibitory concentrations of citral, limonene and eugenol were 0.188, 0.75 and 0.4 μL/mL, and the minimum fungicidal concentrations were 0.375, 3 and 0.8 μL/mL, respectively. Scanning electron microscopy showed that the tested essential oil compounds had destructive effects on the yeast cell surface. After treated by citral, limonene and eugenol, the relative electric conductivity and leakage of nucleic acid were increased significantly. SDS-PAGE analysis indicated that the essential oil components could result in the loss of soluble proteins and might also destroy the yeast protein or inhibit their expression. These results demonstrated that citral, limonene and eugenol exerted their antifungal action against Z. rouxii through cell membrane damage and destruction of cellular proteins. This study provided a theoretical possibility that citral, limonene and eugenol could be used as natural food preservatives for the control of Z. rouxii -related spoilage in the fruit juice industry.