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Abstract: To guarantee consumers about the security of what they eat is the main goal of all the institutions working to assure food safety. In seafood field it appears of prime importance to be able to identify fish species throughout the production cycle also when the product has been already processed (breaded fish, fillets etc). In this context the latest system proposed for species identification is the so called “DNA-Barcoding”, made by carrying out the DNA sequencing of a standard barcode region. In the present study we carried out bi-directional sequence analysis of mitochondrial cytochrome b gene (Cytb) and cytochrome oxidase subunit I gene (COI). The main goal of the research was to unambiguously classify the most common fishes traded in Italy, being able to ascertain possible labeling frauds made substituting value species with less precious ones. With both genes we could correctly identify almost all the samples in study: respectively 58/58 with COI and 56/58 with Cytb. This study confirms mitochondrial genes Cytb and COI as good candidates for fish species identification by DNA sequencing. This method appears particularly suitable especially when morphological characterization is difficult, (for very close species), or impossible (for transformed foodstuffs) to carry out. What's more we could efficiently identify many fishes belonging to the Mediterranean fauna, which, to our knowledge, underwent for the first time this kind of analysis. Further development will concern the extension of the analysis to a largest number of local species. [Copyright &y& Elsevier]

Abstract: Water buffalo milk and derived dairy products, including mozzarella cheese, represent a possible source of Brucella contamination for consumers. Brucella is a severe pathogen for human health even at low concentrations. It is therefore fundamental to develop an assay that is faster and more sensitive than the traditional bacterial culturing method for the detection of the pathogen in the food matrix. We designed a Real-time PCR assay able to detect as low as 1 CFU/ml of Brucella spp. in water (80% probability) and 3 CFU/ml of Brucella spp. in buffalo milk (50% probability) in less than 3 h without any enrichment step. The assay was validated by calculating specificity, sensitivity, detection limit, precision, PCR efficiency, DNA extraction efficiency and food matrix inhibition. When this method was employed to detect and quantify Brucella spp. in 109 buffalo milk samples, the assay demonstrated a higher sensitivity in comparison to bacteriological analysis (27 positive samples and 2 positive samples, respectively). [Copyright &y& Elsevier]

To establish a relationship between viruses and chemicals, they were analysed in oyster Crassostrea gigas from an Italian experimental station. The chemicals concentrations were: Σ6 NDL-PCBs 0.82–7.12 ng g−1; BaP LOQ (<0.2 μg kg−1) to 1.2 μg kg−1; PAH4 LOQ (<0.2 μg kg−1) to 9.8 μg kg−1; Cd 0.073–0.365 mg kg−1; Pb 0.010–0.487 mg kg−1; and Hg < LOQ (0.089 mg kg−1). The viruses identified included: noroviruses (NoVGI/GII), astrovirus (AsV), rotavirus (RV), adenovirus (AdV), and sapovirus (SaV), while hepatitis A, hepatitis E, and Aichi viruses were not detected. Significant correlations were observed for NDL-PCBs with NoVGI, NoVGII, and AdV; BaP and PAH4 with NoVGI and AsV; Cd with RV; Pb with NoVGI and AsV; PAHs with Pb; AsV with NoVGI; and AdV with NoVGII. The study indicated as C. gigas is a model for correlating pollutants and foodborne viruses, whose co-presence may represent an additional food safety risk. [Display omitted] • Oysters accumulated NDL-PCBs, PAHs as well as Cd and Pb. • Oysters accumulated NoV (GI/GII), RV, AsV, SaV and AdV. • HAV, HEV and AiV were not detected in oysters. • Levels of viral and chemical contaminants in oysters showed seasonality. • Correlation between viral and chemical contaminants in oysters was found. [ABSTRACT FROM AUTHOR]