Interaction of Bifidobacterium and Salmonella during associated growth

Interaction of 15 Bifidobacterium (belonging to species B. animalis, B. globosum and B. breve) and six Salmonella (belonging to species S. enteritidis and S. typhimurium) strains was examined during associated growth at optimum conditions for the two genera. All strains of Bifidobacterium investigated were antagonistic to Salmonella. Three strains of Bifidobacterium bactericidal to Salmonella were identified. The kinetics of Salmonella inhibition was as follows: growth of Salmonella was inhibited before the end of the exponential phase, then succeeded by a rapid decrease of live-cell numbers at the beginning of the stationary phase, after which the cell death rate was lower. Growth of Bifidobacterium in the associated cultures was similar to that in monocultures.