Production of ochratoxin A in a semisynthetic medium

Seven Aspergillus and two Penicillium strains were tested for the production of ochratoxin A and B. The isolates were grown on Czapek liquid medium supplemented with varying amounts of sucrose [0-4%]. All of the isolates were capable of producing different levels of ochratoxin A in nutrient medium containing 4% sucrose and 2% yeast extract after 13 days of incubation at 28° as static cultures. Aspergillus ochraceus produced up to 31.36mg/100ml of ochratoxin A and trace amount of ochratoxin B under these conditions. The Penicillium strains produced less ochratoxin A than A. ochraceus