Antibacterial activity of lactic acid bacteria against spoilage and pathogenic bacteria isolated from the same meat small-scale facility: 2—Behaviour of pathogenic and spoilage bacteria in dual species biofilms including a bacteriocin-like-producing lacti

The survival of Listeria innocua ATCC 33090, Staphylococcus aureus E1S-5 and/or Hafnia alvei E1E-25 in dual species biofilms with bacteriocin-like producing lactic acid bacteria (5 Vagococcus carniphilus, 3 Enterococcus faecium, 1 Lactobacillus sakei and 1 Enterococcus sp.) was investigated. The aim was to select strains able to repress the growth of undesirable bacteria in biofilms, i.e., the real mode of bacterial attachment. Two E. faecium and 3 V. carniphilus species were highly antagonistic to L. innocua, S. aureus and H. alvei repressing their growth by reduction levels able to reach 2, 2.7 and 2.4 log10 cfu/ml compared to the positive control made of sole the target microorganism. Furthermore, planktonic cells were more sensitive to the bacteriocin-like substances than sessile ones. First results suggest the possibility of selecting bio-preservatives among the endogenous house flora of the studied small-scale facility, that could be implemented on the processing surfaces to repress the growth of undesirable microorganisms.