Aspergillus carbonarius is a major producer of ochratoxin A in grapes, causing fungal decay and posing a
significant threat to human health. Bacillus subtilis CCTCC M 207209 was used to inhibit the growth of
A. carbonarius CCTCC AF 2011004, an ochratoxin A-producing strain previously isolated from grapes. The
inhibition effect in vitro was tested in potato dextrose agar medium (PDA), while in vivo effects were
examined in grape berries of three different grape cultivars: Thompson Seedless, Kyoho, and Red Earth.
Inhibitory effects were evaluated according to colony size in PDA and rotten spots in grape berries when
A. carbonarius and B. subtilis were inoculated simultaneously and cultivated at 0 C, 25 C, or 30 C.
B. subtilis liquid cultures with and without cells and volatile products were used in the analyses. Significant
inhibition of A. carbonarius was observed in all samples treated with B. subtilis liquid cultures,
especially those subjected to cell-free culture treatment. No inhibition was observed for A. carbonarius
treated with the volatile products of B. subtilis. The inhibition was the most significant in Red Earth
grapes, followed by the Kyoho then Thompson Seedless varieties, when the same fraction of B. subtilis
culture was used. Significant inhibition was also observed for other fungal contaminants in grapes when
B. subtilis liquid culture supernatant was used. This study reveals the potential of B. subtilis for inhibiting
contamination of OTA-producing A. carbonarius and other fungi in table grapes