Lack of correlation between the enterotoxigenicity of Clostridium perfringens isolates and propionic acid formation or amylase activity at 46 degrees C

The absence in the supernatant fluid of either extracellular amylase in cultures grown at 46 degrees C or propionic acid has been proposed for the presumptive identification of enterotoxin-positive strains of Clostridium perfringens. However we found that propionic acid was formed by several enterotoxin-positive, as well as enterotoxin-negative, strains of this organism. In addition 4 of 13 ent(+) stains produced extracellular amylase during growth at 46 degrees C. These results indicate that neither trait can be used as a reliable indicator of the enterotoxigenicity of isolates of this organism