Production of toxic metabolites by Penicillium strains isolated from mold-ripened cheese

Penicillium strains isolated from imported and domestic mold-ripened cheese s were examined for mycotoxin-producing ability by analytical TLC and HPLC. Sixteen of 37 strains of P. roqueforti were able to produce mycophenolic a cid in 2% yeast extract-5% sucrose broth (YES). Twenty-seven of these strai ns had been isolated from imported blue-veined cheese varieties. Of these 2 7 strains, only 5 isolates from Roquefort cheese (14.7 similar to 55.0 mu g /mL) and 2 out of 5 isolates from Danablu cheese (5.3, 17.7 mu g/mL) had my cophenolic acid-producing potential in culture at 14 degrees C. None of the examined strains from Gorgonzola, Stilton and Cambozola cheeses produced m ycophenolic acid. In contrast, 9 out of 10 P. roqueforti strains from domes tic blue-veined cheese were able to produce 4.1 similar to 12.2 mu g/mL myc ophenolic acid. All P. roqueforti strains examined showed the ability to pr oduce roquefortine C. All of 20 strains of P. camemberti isolated from imported and domestic whit e mold cheeses were able to produce 0.05 similar to 6.09 mu g/mL cyclopiazo nic acid in YES broth at 25 degrees C.