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A collection of 25 isolates from foods of animal origin (including mainly milk and cheese, together with meat and ham) was studied. Enterococci were identified at species levels as E. faecalis (9 isolates) and E. faecium (16 isolates). Investigation of virulence factors by PCR amplification revealed incomplete sets of cytolysin genes both in E. faecalis and E. faecium isolates. Among E. faecalis, PCR amplification revealed a high incidence of genes encoding for enterococcal surface protein esp (7/9 isolates), enterococcal antigen efaAfs (6/9), aggregation substance agg (2/9) and sex-pheromone encoding genes ccf, cob, cpd (which were detected in 9, 5 and 3 out of 9 isolates, respectively). By contrast, only esp (7/16 isolates) and efaAfm (10/16) were detected among E. faecium. Antibiotic resistance detected at higher frequencies included rifampicin, nitrofurantoin, ciprofloxacin and levofloxacin. Vancomycin resistance was also detected among E. faecalis and E. faecium. E. faecalis isolates showed decarboxylating activity mostly for tyrosine (5/9 isolates), while E. faecium isolates showed a broader decarboxylating capacity, involving tyrosine (11/16 isolates) ornithine (6/16), lysine (4/16) and histidine (3/16). Six isolates produced bacteriocins, and genes encoding for enterocins A, B, P, L50, and 1071 were detected. Many isolates tested positive for several of the traits investigated, which raises concerns about their possible role as reservoirs for dissemination of antibiotic resistance and virulence traits in foods.

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.