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The complete nucleotide sequence of the mitochondrial (mt) genome of the demersal zebra seabream Diplodus cervinus (Lowe, 1838) was determined for the first time. The double stranded circular molecule is 16,559 base pairs (bp) in length and encodes for the typical 37 metazoan mitochondrial genes, and 2 non-coding regions (D-loop and L-origin). The gene arrangement of the D. cervinus mt genome follows the usual one for fishes. The nucleotide sequences of the mt protein coding and ribosomal genes of D. cervinus mt genome were aligned with orthologous sequences from representatives of the Sparidae family and phylogenetic relationships were inferred. Maximum likelihood analyses placed D. cervinus as a sister species of Diplodus sargus (Linnaeus, 1758).

Dentex gibbosus (Pink dentex) is a fish species of increasing economic interest in the Mediterranean Sea that is consumed both whole and processed. The growing value of this sparid in European markets is responsible for its substitution with fraudulent species. The distinctive morphologic feature of D. gibbosus is the conspicuous hump on the forehead in the older and larger specimens. However, the head is regularly convex in young individuals, requiring high skills and competencies for correct identification. Authentication becomes even more challenging in the case of prepared and processed products. Therefore, the molecular characterization of Pink dentex plays a crucial role in preventing commercial fraud with species substitution. This paper proposes a comparative mitogenome analysis between 19 sparid species of commercial interest as a tool to accurately design species-specific primers targeting a fragment of the NAD2 gene for the identification of D. gibbosus. We successfully detected Pink dentex DNA both using endpoint and real-time PCR. The findings showed the high specificity of the designed primers, demonstrating this a suitable, fast, and cost-effective method that could be used for the unambiguous identification of Pink dentex. This innovative approach for sparid authentication is expected to contribute to seafood traceability, public health assurance, integrity, and the credibility of the seafood industry.

L. monocytogenes is a foodborne pathogen responsible for a serious disease with a high mortality rate, particularly in vulnerable consumers. Recently, the scientific community has shown increasing attention to the search for new natural molecules with antimicrobial activity, aimed at preventing the spread of foodborne diseases. Extremophilic microorganisms, typical of extreme temperature environments, are a valuable source of these molecules. The present work aimed to study the antibacterial activity of four pure compounds derived from a molecule, the pentadecanal, produced by the Antarctic bacterium Pseudoalteromonas haloplanktis, against two different pathotypes of L. monocytogenes. Growth assays were performed in 96-well polystyrene plates with serial dilutions of the tested compounds at different concentrations (0.6, 0.3, 0.15, 0.07 mg/mL). The plates were incubated at 37°C for 24 h, with a spectrophotometric reading at OD 600 nm. Preliminary results of this study showed that pentadecanal inhibits the growth of L. monocytogenes, with a MIC (Minimum Inhibitory Concentration) of 0.6 mg/mL. Acetal, carboxylic acid, and ester did not demonstrate antibacterial activity at the concentrations tested. These findings suggest the possibility of using pentadecanal as a natural antibacterial to improve safety standards along the food supply chain.

The white seabream Diplodus sargus (Linnaeus, 1758) is a species of interest for commercial fisheries throughout its range of distribution and it is also reared using aquaculture techniques. Herein, we present the first complete sequence and annotation of the mitochondrial genome of this species. The D. sargus mitogenome is 16,515 base pairs in length and contains 13 protein-coding genes, 2 rRNA, 22 tRNA, and 2 non-coding regions (D-loop and L-origin). The overall nucleotide composition is: 27.3% A, 28.9% C, 26.8% T, and 17.0% G. Maximum likelihood analyses placed D. sargus as a sister species of Diplodus puntazzo. This study provides valuable information for further studying identification methods and evolutionary relationships of Sparidae species.

The increasing world market demand for seafood requires an expansion of product categories available to consumers. Inland fish are usually considered having unmarked taste and are less appreciated by consumers; thus, they have low commercial value. Therefore, the marketing of the lake’s fresh and processed fish is limited to the local market and consumers are currently uninformed and mistrustful about these species. In this study, six different fish species were caught in the Fondi lake (Lazio, central Italy): Anguilla anguilla, Tinca tinca, Carassius gibelio, Cyprinus carpio, Micropterus salmoides, Chelon ramada. All the samples were subjected to nutritional and DNA barcoding analysis. Moisture, protein, fat, carbohydrates, ash, and sodium content were measured. As regards the fatty acids profile, the most abundant were MUFAs with the highest value in Anguilla anguilla (45.97%). Oleic acid (C18: 1 n9 cis) was particularly high in Cyprinus carpio (55.46%). The fraction of polyunsaturated fatty acids (PUFA) revealed a higher DHA content (C22: 6 n3) in Anguilla anguilla than the other species (>12 %) while Chelon ramada presented both higher EPA content (C 20: 5 n3) and total fraction of omega 3 PUFAs. Concerning molecular analysis, a 655 bp fragment of cytochrome C oxidase subunit I (COI) gene was successfully used for the identification at the species level using both BOLD and BLAST public databases. The present study gives the basis for improving the knowledge and promoting inland fish’ market and traceability along the supply chain.

The sharpsnout seabream Diplodus puntazzo Walbaum, 1792 is a target species of small-scale fishery activities and is cage-cultured for human consumption. Nonetheless, genetic information on this species is limited. We here first sequence its complete mitochondrial genome. The sequence is composed of 16,638 base pairs, accounting for 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes, and 2 non-coding regions (D-loop and L-origin). The overall nucleotide composition is: 27.4% A, 28.9% C, 26.9% T, and 16.8% G. Maximum likelihood analyses placed D. puntazzo close to Acanthopagrus and some Pagellus species.

The levels of PCDDs, PCDFs and DL-PCBs were analyzed both in milk and adipose tissues sampled “in vivo” from lactating, drying off and heifer buffaloes from a Campania farm which had been impounded by the competent authority owing to the high dioxin levels found in bulk milk. The chemical determination was carried out by HRGC-HRMS using US EPA Method 1613b. The range of WHO-TEQ values for the PCDDs/PCDFs in adipose tissues was 1.79 to 68.64 pg g−1 fat and in milk was 8.33 to 13.95 pg g−1 fat. The contamination profile for dioxins and furans was given by 1,2,3,7,8-PeCDD; 2,3,4,7,8-PeCDF; 1,2,3,6,7,8-HxCDD and 2,3,7,8-TCDD. The levels of DL-PCBs in adipose tissue varied from 1.38 to 20.13 pg g−1 fat while ranged from 8.33 to 13.95 pg g−1 fat in milk. The pattern of DL-PCBs in both matrices was dominated by congeners PCB 126 and PCB 169.

The common dentex (Dentex dentex (Linnaeus, 1758)) is an iconic fish in the Mediterranean diet. Due to its commercial and organoleptic importance, this sparid is highly appreciated in European markets and is often subjected to species substitution frauds. Comparative mitogenomics is a suitable approach for identifying new and effective barcode markers. This study aimed to find a molecular tag useful for unequivocally discriminating the sparid species D. dentex. The comparison of the complete mitochondrial DNA (mtDNA) sequences of 16 sparid species allowed us to highlight the potential of the NAD2 gene for direct identification purposes. Common dentex-specific primers were created and successfully evaluated by end-point and real-rime PCR (Polymerase Chain Reaction) for several fish species, achieving amplification only in the D. dentex. The method proposed in this study appears fast, simple, and inexpensive and requires affordable instrumentation. This approach provides unambiguous results for the common dentex authentication without the sequencing step. The presence/absence assay for D. dentex can be executed in a few hours of lab work. Therefore, national authorities responsible for food safety and traceability could apply and make full use of DNA-testing methods for deterring operators from false seafood declarations.

The commercialization of porgies or seabreams of the family Sparidae has greatly increased in the last decade, and some valuable species have become subject to seafood substitution. DNA regions currently used for fish species identification in fresh and processed products belong to the mitochondrial (mt) genes cytochrome b (Cytb), cytochrome c oxidase I (COI), 16S and 12S. However, these markers amplify for fragments with lower divergence within and between some species, failing to provide informative barcodes. We adopted comparative mitogenomics, through the analysis of complete mtDNA sequences, as a compatible approach toward studying new barcoding markers. The intent is to develop a specific and rapid assay for the identification of the common pandora Pagellus erythrinus, a sparid species frequently subject to fraudulent replacement. The genetic diversity analysis (Hamming distance, p-genetic distance, gene-by-gene sequence variability) between 16 sparid mtDNA genomes highlighted the discriminating potential of a 291 bp NAD2 gene fragment. A pair of species-specific primers were successfully designed and tested by end-point and real-time PCR, achieving amplification only in P. erythrinus among several fish species. The use of the NAD2 barcoding marker provides a rapid presence/absence method for the identification of P. erythrinus.

Listeria monocytogenes is a foodborne pathogen responsible for about 1600 illnesses each year in the United States (US) and about 2500 confirmed invasive human cases in European Union (EU) countries. Several technologies and antimicrobials are applied to control the presence of L. monocytogenes in food. Among these, the use of natural antimicrobials is preferred by consumers. This is due to their ability to inhibit the growth of foodborne pathogens but not prompt negative safety concerns. Among natural antimicrobials, plant extracts are used to inactivate L. monocytogenes. However, there is a large amount of these types of extracts, and their active compounds remain unexplored. The aim of this study was to evaluate the antibacterial activity against L. monocytogenes of about 800 plant extracts derived from plants native to different countries worldwide. The minimal inhibitory concentrations (MICs) were determined, and scanning electron microscopy (SEM) was used to verify how the plant extracts affected L. monocytogenes at the microscopic level. Results showed that 12 of the plant extracts had inhibitory activity against L. monocytogenes. Future applications of this study could include the use of these plant extracts as new preservatives to reduce the risk of growth of pathogens and contamination in the food industry from L. monocytogenes.

The complete mitochondrial genome of the Angolan dentex (Dentex angolensis, Poll and Maul, 1953) is 16.581 bp in length and contains 13 protein-coding genes, 22 transfer RNA genes, and 2 ribosomal RNA genes. The overall base composition of D. angolesis mtDNA is: 27.4% for A, 28% for C, 16.7% for G, 27.9% for T. Phylogenetic analysis indicated that D. angolensis is most closely related to D. tumifrons. Whole genome sequencing of D. angolensis mitochondrial DNA will contribute to improving knowledge about Sparidae evolution.

Previous studies showed that fish mitochondrial DNA (mtDNA) is set up by a closed circular molecule of 16-17 kilobases (kb), comprising 2 ribosomal RNA genes (rRNA), 22 transfer RNA genes (tRNA), 13 protein-coding genes and 2 non-coding regions. The analysis of single mtDNA genes, such as Cytb, COI, 16S and 12S, or short segment of them, has been widely used against species substitution in both fresh and processed fish products. The analysis of the complete mitochondrial genome of fishery products allows to better study and characterise fish species. The aim of this research was to extract and amplify the complete mtDNA of some fish species of commercial interest belonging to the Sparidae family. The studied species were Dentex dentex, Dentex gibbosus, Dentex nufar, Pagellus acarne and Pagellus erythrinus. The entire mitogenome was obtained by gene amplification using long polymerase chain reactions. The analysis of the complete mitochondrial sequences will allow to gain further insights on these species and to find polymorphic sites that assess the degree of genetic variability of the species belonging to the family Sparidae.

The Pink dentex (Dentex gibbosus, Rafinesque 1810) is one of the most commercially important Sparidae species and it is often subjected to fraud. Here, we report the complete mitochondrial genome of D. gibbosus. The mitogenome is 16,771 bp in length and contained 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes and 2 non-coding regions. The overall base composition of D. gibbosus mtDNA is: 27.8% for A, 28.60% for C, 16.5% for G, 27.05% for T.

The common pandora (Pagellus erythrinus, Linnaeus 1758), one of the most popular sea bream species in the Mediterranean Sea, has high potential for aquaculture development. In this investigation, we analyzed the complete mitochondrial genome of P. erythrinus. The sequence has 16,828 bp in length and consists of 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes, and a two non-coding regions (D-loop and L-origin). The overall nucleotide composition is: 27.5% of A, 28.2% of C, 27.5% of T, and 16.8% of G.

The common Dentex (Dentex dentex, Linnaeus 1758) has a significant economic importance and is a highly valued table fish in the Mediterranean region. The paucity of genetic information relating to sparids, despite their growing economic value, provides the impetus for exploring the mitogenomics of this fish group. Here, we sequenced D. dentex complete mitochondrial genome. The sequence is comprised of 16,652 bp and consists of 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes and a 2 non-coding regions (D-loop and L-origin). The overall nucleotide composition is: 27.5% of A, 28.7% of C, 26.9% of T, and 16.9% of G.

The axillary seabream (Pagellus acarne, Risso 1827) belongs to the Sparidae family, order Perciformes. This high-valued commercial fish species is distributed along the northern and eastern Atlantic coasts from Norway to Senegal, and throughout the Mediterranean Sea. Its complete mitochondrial genome is 16,486 bp in length, consisting of 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes, and 2 non-coding regions (D-loop, 808 bp and L-origin, 29 bp). Its overall base composition is A: 26,8%, C: 29,0%, G: 17.6%, and T: 26.6%.

In this study, four protein extraction protocols from Mytilus galloprovincialis were evaluated with the aim to identify the most practical, efficient and reproducible method. Four extraction protocols frequently used for mussels and organic matrices were selected and compared. The methods were based on the use of: i) TRIzol reagent; ii) Lysis buffer; iii) phenylmethanesulfonyl fluoride; iv) trichloroacetic acid-acetone. Protein concentration was measured by the Bradford method. Three specimens of mussels were studied and the analysis was conducted in triplicate for each of the four protocols. Results indicated that the four methods could extract significantly different protein profiles. The highest number of protein spots resolved in 2DE gels and the best reproducibility was obtained using trichloroacetic acid-acetone protocol. Results afforded the selection of a suitable extraction protocol to be used for ecotoxicoproteomics studies from mussels and for other proteomic studies conducted by particularly complex tissues such as Mytilus galloprovincialis.

Listeria monocytogenes (Lm) is a food-borne pathogen responsible for human listeriosis, an invasive infection with high mortality rates. Lm has developed efficient strategies for survival under stress conditions such as starvation and wide variations in temperature, pH, and osmolarity. Therefore, Lm can survive in food under multiple stress conditions. Detailed studies to determine the mode of action of this pathogen for survival under stress conditions are important to control Lm in food. It has been shown that genes encoding for ATP-binding cassette (ABC) transporters are induced in Lm in food, in particular under stress conditions. Previous studies showed that these genes are involved in sensitivity to nisin, acids, and salt. The aim of this study was to determine the involvement of some ABC transporters in biofilm formation. Therefore, deletion mutants of ABC transporter genes (LMOf2365_1875 and LMOf2365_1877) were created in Lm F2365, and then were compared to the wild type for their capacity to form biofilms. Lm strain F2365 was chosen as reference since the genome is fully sequenced and furthermore this strain is particularly involved in food-borne outbreaks of listeriosis. Our results showed that DLMOf2365_1875 had an increased capacity to form biofilms compared to the wild type, indicating that LMOf2365_1875 negatively regulates biofilm formation. A deeper knowledge on the ability to form biofilms in these mutants may help in the development of intervention strategies to control Lm in food and in the environment.

The aim of this work is to present the preliminary results of a study about the prevalence of Campylobacter jejuni in poultry breeder flocks. It was examined three different breeder flocks of Bojano in Molise region. A total of 360 cloacal swabs and 80 enviromental swabs was collected. Of the 3 flocks studied, 6.9% tested were positive for Campylobacter spp. The most-prevalent isolated species is C. jejuni (8.2%). Only 3 of the 360 cloacal swabs samples examined were associated with C. coli. The environmental swabs resulted negative. This results confirms again that poultry is a reservoir of this germ.

Functional genomics approaches enable us to investigate the biochemical, cellular, and physiological properties of each gene product and are nowadays applied to enhance food safety by understanding microbial stress responses in food and host-pathogen interactions. Listeria monocytogenes is a food-borne pathogen that causes listeriosis and is difficult to eliminate this pathogen since it can survive under multiple stress conditions such as low pH and low temperature. Detailed studies are needed to determine its mode of action and to understand the mechanisms that protect the pathogen when it is subjected to stress. In this study, deletion mutants of phosphotransferase transport system genes (PTS) and adenosine triphosphate(ATP)-binding cassette transporters (ABC) of Listeria monocytogenes F2365 were created using molecular techniques. These mutants and the wild-type were tested under different stress conditions, such as in solutions with different NaCl concentration, pH value and for nisin resistance. Results demonstrate that the behaviour of these deletion mutants is different from the wild type. In particular, deleted genes may be involved in L. monocytogenes resistance to nisin and to acid and salt concentrations. Functional genomics research on L. monocytogenes allows a better understanding of the genes related to stress responses and this knowledge may help in intervention strategies to control this food-borne pathogen. Furthermore, specific gene markers can be used to identify and subtype L. monocytogenes. Thus, future development of this study will focus on additional functional analyses of important stress response-related genes, as well as on methods for rapid and sensitive detection of L. monocytogenes such as using DNA microarrays.

Nitroxynil (NIT) is a halogenated phenol used to control fascioliasis in cattle and sheep. The Commission Regulation EU No 37/2010 has established maximum residue limits for NIT in bovine and ovine muscle (400 μg kg−1), fat (200 μg kg−1), liver (20 μg kg−1) and kidney (400 μg kg−1), and more recently in bovine and ovine milk (20 μg kg−1). Thirty-five pregnant dairy cows were treated in this study with nitroxynil (340 mg/mL solution for injection) at the recommended dose of 10 mg/kg body weight at the start of the dry period, i.e. 53 to 74 days before the expected calving. Calving occurred between 43 days and 79 days after treatment. The concentrations of NIT in the milk were monitored for up to 120 days after calving. NIT residues were extracted using acetonitrile; magnesium sulfate and sodium chloride were added to induce liquid-liquid partitioning and purified by dispersive solid phase extraction for clean-up. NIT was detected by ultra high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS) in negative ionization mode. The highest concentrations of this drug were found in two animals at the first milking, 48 and 53 day post treatment with levels of 362 and 657 μg kg–1, respectively. NIT residues were below the limit of detection of the method (0.24 μg/kg–1) between 67 and 106 day post-treatment. Following calving, residues rapidly depleted in animals and were non-detectable from 10 to 38 days post-calving. In particular, in all animals milk resulted compliant (post partum.