The purpose of an enrichment broth is to amplify very low levels of a specific bacterium within 24 hours so it can be more readily identified and isolated by a subsequent methodology. In situations where cells of the targeted bacterium are very low and injury is high, such cells must undergo repair without deleterious effects. The broth must also contain selective agents to suppress background growth which can interfere with the isolation of the target bacterium. Our selective non-O157 STEC enrichment broth permits the proliferation of both injured and non-injured non-O157 STEC strains which includes the 6 major serogroups while suppressing the growth of competing flora.

1. Our broth supported the growth of 28 non-O157 STEC strains (which included the 6 major serogroups) with a similar final cells density as cells grown in Tryptic Soy Broth (TSB), whereas the USDA listed modified Tryptone Soya Broth (m-TSB) inhibited the growth of more than 20% of these strains incubated at 41-42°C for 20-22 hours.