title: Listeria MonocytogenesPersistence in Ready-to-Eat Sausages and in Processing Plants.
abstract: Listeria monocytogenesis of major concern in the fermented meat products and is able to persist in their processing environments. The aim of the present work was to evaluate the virulence profile and the persistence capacity ofL. monocytogenesstrains isolated in Sardinian fermented sausages processing plants. Food (ground meat, sausages at the end of acidification and ripening stage) and environmental samples (a total of n. 385), collected from 4 meat processing plants located in Sardinia (Italy), were examined to detectL. monocytogenespresence. All theL. monocytogenesisolates were identified by polymerase chain reaction (PCR) method. A subset of strains was also characterised by multiplex PCR-based serogrouping, using thelmo0737,lmo1118,ORF2819andORF2110genes. Three different multiplex PCRs were used to obtain the virulence profiles by therrn,hlyA,actA,prfA,inlA,inlB,iap,plcA,plcBandmplmarker genes. Furthermore,in vitrobiofilm forming ability and resistance to disinfectants were carried out on microtiter plate. The overall prevalence was 31.5% in food, and 68.5% in environmental samples. The prevalent serotype resulted 1/2c (43%), followed by 1/2a (40%), 4b (8.6%), and 1/2b (8.6%). The amplification products of the virulence genes were found in all the isolates with the following prevalence: 77.1%hlyA; 100%rrn; 100%prfA; 97.1%iap; 65.7%inlB; 88.6%inlA; 100%plcA; 100%plcBand 74.3%mpl. As for biofilm forming ability, 37.1% of the strains were positive and resulted weak producer, but all the isolates were sensible to disinfectants showing a reduction ofL. monocytogenesgrowth after each incubation time. More appropriate technologies and application of measures of hygienic control should be implemented to prevent theL. monocytogenesgrowth and cross-contamination insalsiccia sardaprocessing plants.
authors: Settore di Ispezione degli Alimenti di Origine Animale, Dipartimento di Medicina Veterinaria, Università di Sassari , Italy.
authors: Anna
authors: A
authors: Mureddu
authors: Settore di Ispezione degli Alimenti di Origine Animale, Dipartimento di Medicina Veterinaria, Università di Sassari , Italy.
authors: Roberta
authors: R
authors: Mazza
authors: Settore di Ispezione degli Alimenti di Origine Animale, Dipartimento di Medicina Veterinaria, Università di Sassari , Italy.
authors: Federica
authors: F
authors: Fois
authors: Settore di Ispezione degli Alimenti di Origine Animale, Dipartimento di Medicina Veterinaria, Università di Sassari , Italy.
authors: Domenico
authors: D
authors: Meloni
authors: Settore di Ispezione degli Alimenti di Origine Animale, Dipartimento di Medicina Veterinaria, Università di Sassari , Italy.
authors: Roberto
authors: R
authors: Bacciu
authors: Settore di Ispezione degli Alimenti di Origine Animale, Dipartimento di Medicina Veterinaria, Università di Sassari , Italy.
authors: Francesca
authors: F
authors: Piras
authors: Settore di Ispezione degli Alimenti di Origine Animale, Dipartimento di Medicina Veterinaria, Università di Sassari , Italy.
authors: Rina
authors: R
authors: Mazzette
keywords: Biofilm; Disinfectant resistance; Listeria monocytogenes; Salsiccia sarda