[The detection of toxinogenic Bacillus cereus strains]

Investigations into optimal culture conditions for Bacillus cereus in order to detect bacterial toxins in a cell culture system showed that Dulbecco's modified Eagle's medium supplemented with 5% fetal calf serum is the medium best suited for this purpose. The highest toxicity levels were seen when bacteria were cultured at 21 degrees C. In 42 of 43 Bacillus cereus-strains isolated from milk and milk products, toxin formation was detected using the MTT-test. In 11 strains, toxin formation was even shown when bacteria were cultured at 4 degrees C. When culture supernatants were examined in a commercially available ELISA, all cytotoxic strains were shown to form diarrheal toxin.