Inhibition of food poisoning and pathogenic bacteria by Lactobacillus plantarum strain 2.9 isolated from ben saalga, both in a culture medium and in food

The bacteriocinogenic strain Lactobacillus plantarum 2.9 isolated from the traditional pearl millet-based African fermented food ben saalga was tested for inhibition of food poisoning and pathogenic bacteria in MRS broth and in a malted millet flour slurry. In MRS broth, strain 2.9 completely eliminated Bacillus cereus, Escherichia coli O157:H7 and Salmonella enterica cells within 48 h incubation at 22–30 °C. A much lower inhibition was observed at 15 °C. The inhibitory effect of strain 2.9 on the above-mentioned target bacteria was corroborated in the malted millet flour slurry, reducing viable cell counts below detection levels after 8 h storage for B. cereus or after 24 h for S. enterica and 48 h for E. coli. An Enterobacter aerogenes strain was only moderately inhibited in the slurry. Results from the present study suggest that strain 2.9 could be used as starter culture to improve the microbiological safety of fermented ben saalga.