Production of patulin and citrinin by penicillium expansum from British columbia (Canada) apples

Twenty-four isolates of Penicillium expansum Link from British Columbia (Canada) apples were cultured in yeast-extract sucrose (YES) at 25°C for 28 days to investigate production of patulin and citrinin. These isolates proved to be potent producers of citrinin, patulin, or in most cases, both mycotoxins. In every isolate, citrinin, patulin, or both compounds were produced at levels as high as 565 μg/mL (mean 269 μg/mL) and 100 μg/mL (mean 31 μg/mL), respectively. Of the 24 isolates, 4 produced citrinin only, and 2 produced patulin only. Overall, 83% of the isolates formed patulin and 91% formed citrinin. YES broth proved to be an effective medium for patulin and citrinin production. Other workers have noted that production of these mycotoxins in culture often presages production in fruits, so these results might help Canadian fruit processors evaluate and minimize mycotoxin levels in their products. © 2009 Society for Mycotoxin Research and Springer.