The ability of S. cerevisiae and LAB strains to bind AFM1 was
evaluated using commercial UHT skim milk samples previously
evaluated for AFM1 to confirm levels below the detection limit of
the method (0.01 ng mL1), spiked with 0.5 ng mL1. AFM1 standard
solution (Supelco, Bellefonte, PA, USA) was diluted in
acetonitrile in order to obtain a 2.5 mg mL1 working solution,
which was calibrated according to Scott (1990). Two-hundred
microliters of the working solution were transferred to an Erlenmeyer,
evaporated to dryness under N2 and then 1 L of UHT skim
milk was added to the flask. Spiked milk samples were stirred, kept
at 37 C for 15 min, and immediately used in the binding assays
with S. cerevisiae and LAB strains.