Growth reduction of Listeria spp. caused by undefined industrial red smear cheese cultures and bacteriocin-producing Brevibacterium lines as evaluated in situ on soft cheese

Abstract

The undefined microbial floras derived from the surface of ripe cheeses which are used for the ripening of commercial red smear cheeses have a strong impact on the growth of Listeria spp. In some cases, these microbial consortia inhibit Listeria almost completely. From such undefined industrial cheese-ripening floras, linocin M18-producing (lin ؉) (N. Valdés-Stauber and S. Scherer, Appl. Environ. Microbiol. 60:3809-3814, 1994) and-nonproducing Brevibacterium linens strains were isolated and used as single-strain starter cultures on model red smear cheeses to evaluate their potential inhibitory effects on Listeria strains in situ. On cheeses ripened with lin ؉ strains, a growth reduction of L. ivanovii and L. monocytogenes of 1 to 2 log units was observed compared to cheeses ripened with lin strains. Linocin M18 activity was detected in cheeses ripened with lin ؉ strains but was not found in those ripened with lin strains. We suggest that production of linocin M18 contributes to the growth reduction of Listeria observed on model red smear cheeses but is unsufficient to explain the almost complete inhibition of Listeria caused by some undefined microbial floras derived from the surface of ripe cheeses.

Comparative genomic analysis of Brevibacterium strains: insights into key genetic determinants involved in adaptation to the cheese habitat

“…Its activity against Listeria spp. has also been demonstrated in a model cheese [ 87 ]. In our study, linocin M18-related bacteriocins were detected in 15 of the 23 investigated genomes, belonging to different phylogenetic groups and isolated from different habitats.…”

Characterization of an antibacterial peptide produced by Brevibacterium linens

“…In some cases, these microbial consorts almost completely inhibited Listeria species. Growth reduction of L. ivanovii and L. monocytogenes was observed on cheese ripened with a bac + strain (Eppert et al 1997). However, increased tolerance of L. monocytogenes to conventional bacteriocins, such as nisin and pediocin, has been reported (Rasch and Knochel 1998;van Schaik et al 1999).…”

Chemical and genetic characterization of bacteriocins: antimicrobial peptides for food safety

“…152 Many bacteriocins applied in food systems reduce Listeria by only 1 or 2 logs. 153 Subsequently, additional controls in the form of mild processing treatments or other additives may be necessary to achieve a sufficient kill. 154 -156 Hurdle technologies must be carefully reviewed prior to application for the possibility of adaptation of the target pathogen since any single control is assumed to kill only a portion of the target population.…”