title: Listeria monocytogenes-carrying consortia in food industry. Composition, subtyping and numerical characterisation of mono-species biofilm dynamics on stainless steel.
abstract: In order to find out how real Listeria monocytogenes-carrying biofilms are in industrial settings, a total of 270 environmental samples belonging to work surfaces from fish (n = 123), meat (n = 75) and dairy industries (n = 72) were analysed in order to detect L. monocytogenes. 12 samples were positive for L. monocytogenes and a total of 18 different species were identified as accompanying microbiota in fish and meat industry. No L. monocytogenes was found in samples from dairy industry. Molecular characterisation combining results of AscI and ApaI macrorestriction PFGE assays yielded 7 different subtypes of L. monocytogenes sharing in 71.43% of cases the same serogroup (1/2a-3a). Results from dynamic numerical characterisation between L. monocytogenes monospecies biofilms on stainless steel (SS) using MATLAB-based tool BIOFILMDIVER demonstrated that except in isolate A1, in which a significant increase in the percentage of covered area (CA), average diffusion distance (ADD) and maximum diffusion distance (MDD) was observed after 120 h of culture, no significant differences were observed in the dynamics of the rest of the L. monocytogenes isolates. Quantitative dual-species biofilm association experiments performed on SS indicated that L. monocytogenes cell counts presented lower values in mixed-species cultures with certain species at 24 and 48 h compared with mono-species culture. However, they remained unaltered after 72 h except when co-cultured with Serratia fonticola which presented differences in all sampling times and was also the dominant species within the dual-species biofilm. When considering frequency of appearance of accompanying species, an ecological distribution was demonstrated as Escherichia coli appeared to be the most abundant in fish industry and Carnobacterium spp. in meat industry.
authors.affiliation: Department of Microbiology and Technology of Marine Products, Instituto de Investigaciones Marinas (IIM-CSIC), Eduardo Cabello 6, 36208 Vigo, Pontevedra, Spain; Department of Genetics and Microbiology, Faculty of Biosciences, Autonomous University of Barcelona, Campus of Bellaterra, 08193 Bellaterra, Catalonia, Spain.
authors.forename: Pedro
authors.initials: P
authors.lastname: Rodríguez-López
authors.affiliation: Department of Microbiology and Technology of Marine Products, Instituto de Investigaciones Marinas (IIM-CSIC), Eduardo Cabello 6, 36208 Vigo, Pontevedra, Spain. Electronic address: paula.saaibusquiza@wur.nl.
authors.forename: Paula
authors.initials: P
authors.lastname: Saá-Ibusquiza
authors.affiliation: Department of Microbiology and Technology of Marine Products, Instituto de Investigaciones Marinas (IIM-CSIC), Eduardo Cabello 6, 36208 Vigo, Pontevedra, Spain.
authors.forename: Maruxa
authors.initials: M
authors.lastname: Mosquera-Fernández
authors.affiliation: Department of Microbiology and Technology of Marine Products, Instituto de Investigaciones Marinas (IIM-CSIC), Eduardo Cabello 6, 36208 Vigo, Pontevedra, Spain. Electronic address: marta@iim.csic.es.
authors.forename: Marta
authors.initials: M
authors.lastname: López-Cabo
mesh_terms: D018441:Biofilms; D019649:Food Industry; D005516:Food Microbiology; D008089:Listeria monocytogenes / Q000302:isolation & purification / Q000502:physiology*; D013193:Stainless Steel
chemical_list: D013193:Stainless Steel
keywords: Biofilm; Food safety; Listeria monocytogenes; Survey