Method for Isolation of Escherichia coli O157: H7 from Radish Sprouts: A Collaborative Study

Twenty laboratives participated in a collaborative study to evaluate methods for isolating Escherichia coil O157: H7 from radish sprouts. The collaborators attempted to isolate the organism from 25 g of radish sprouts inoculated with 28.3 CFU E. coli O157: H7, using enrichment and plating methods. E. coli O157: H7 could be isolated from most samples after being cultured at 42°C for 18 h in a modified EC broth supplemented with novobiocin but not after being cultured at 37°C for 6 h in tryptic soy broth.