Isolation of human faecal bifidobacteria which reduce signs of Salmonella infection when orogastrically dosed to mice

Aims: The aim of the study was to isolate human bifidobacteria that inhibit growth of Salmonella typhimurium in vitro, and provide protection against Salmonella infection in mice. Methods and Results: A total of 92 micro-organisms, which displayed antagonist activity against Saint. typhimurium in vitro, were isolated from human faecal material. Based on their Gram stain status, cultures were pooled and tested for anti-Salmonella activity. The Gram-variable group was the most active. From that group, three bifidobacteria (Lafti(TM)B22, B74 and B97) individually showed good pathogen inhibition in vivo. Conclusions: Oral administration of certain human bifidobacteria provides protection against Salmonella infection in mice. Significance and Impact of the Study: These results indicate that certain bifidobacteria may be used as a prophylaxis for reduced incidence and severity of Salmonella infections.