Inhibition of ochratoxin A production in Aspergillus carbonarius by hydroxycinnamic acids from grapes

Hydroxycinnamic acids (HCAs), phenolic components of wine, are known to have antimicrobial properties. Aspergillus carbonarius is one of the most important ochratoxin A (OTA) producing fungi in wine. Strategies for the control and prevention of A. carbonarius contamination are important for the maintenance of wine safety. This study sought to determine the potential of HCAs, such as caffeic, p-coumaric and ferulic acids, as antifungal natural compounds for the control of A. carbonarius growth and OTA production. The HCAs were tested at the increasing concentrations of 0.30, 0.65 and 1.10 mg/ml in minimal medium (MM) and grape juice. Germination of conidia was not affected in neither of the two media in presence of HCAs. At all the concentrations tested, OTA biosynthesis in MM was reduced and the dose effect was more evident for p-coumaric and ferulic acids; in grape juice the reduction trend was confirmed, and ferulic acid showed the highest inhibitory effect. Moreover, the expression level of genes encod...