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This review was focused on the genetic polymorphism of the calcium sensitive caseins (αs1, β, αs2) of goat milk. Mutational events characterising the different allelic variants were reported. The molecular events responsible for the different level of expression (normal, intermediate, null) that characterise the alleles of the same gene were reported. Furthermore, relations between genetic polymorphism and structural, compositional and technological characteristics of goat milk were considered. Finally, the role of genetic polymorphism of casein 〈s2 in allergic forms to milk for infants. In fact, recent research indicates that the casein 〈s2 is responsible for the onset of allergic forms, consequently, the use of a milk lacking this casein fraction could reduce this phenomenon of intolerance.

Il gene MBL codifica per una proteina (Mannose Binding Lectin) che ha una funzione determinante nel sistema del complemento. Tale proteina lega specificamente residui di mannosio, fucosio e di altri zuccheri presenti sulle superfici cellulari di patogeni, ma assenti nei vertebrati. In questo modo la MBL è in grado di discriminare il tipo di membrana di attacco e innescare l'attivazione del complemento esclusivamente sulla superficie del patogeno. Lo scopo della presente ricerca è stato lo studio della variabilità genetica al locus MBL nella specie caprina finalizzata all’individuazione di marcatori utili per studi di associazioni alla resistenza nei confronti della Brucella melitensis. Per 3 capre appartenenti ad una popolazione locale allevata in provincia di Catanzaro, è stato sequenziato il gene MBL dal 1° nucleotide del 1° esone al 417° nt del 4° esone per un totale di 3538 bp più 978 basi della regione 5’ UT. Tale gene è organizzato in 4 esoni e 3 introni. L’ORF (Open Reading Frame) codifica per 249 residui aminoacidici, mentre il peptide leader è costituito da 19 aminoacidi. Dal confronto tra le sequenze ottenute dai tre soggetti esaminati sono stati evidenziati un totale di 12 SNP. Al fine di effettuare una genotipizzazione e verificare se esista o meno un’associazione tra tali SNP e la resistenza alla Brucella melitensis sono state scelte 5 delle 12 mutazioni individuate. Delle 5 mutazioni, 4 (G→A-892, C→A-62, G→A116ex2, T→G190int2) sono strettamente associate (fase cis) e, quindi, possono essere considerate come un unico locus biallelico: A e B. La mutazione G→A-802 è stata esclusa in quanto presente con bassa frequenza nella popolazione esaminata. Il fenotipo per ciascun soggetto in esame è stato ottenuto attraverso la determinazione dell’attività antimicrobica verso la Brucella melitensis in vitro, sulla base della differenza tra il valore logaritmico ottenuto dalla conta delle colonie sviluppatesi su una piastra contenente siero sottoposto a trattamento termico per disattivare le proteine del sistema del complemento (siero non attivo) ed una contenente siero non sottoposto a trattamento (siero attivo). I dati ottenuti su un totale di 218 sieri individuali di capra vanno da un minimo di 0,01, che indica la massima suscettibilità al patogeno ad un valore di 1,47 che rappresenta, invece, la massima resistenza. Per la realizzazione della correlazione sono state create due classi fenotipiche (0,01 a 0,74 e 0,75 a 1,47) e sono stati presi in i tre genotipi: AA, AB e BB. Successivamente, è stato calcolato il valore dell’odds ratio che permette di verificare una eventuale associazione tra genotipo e resistenza alla Brucella melitensis. Il calcolo dell’odds ratio (OR) mostra per tale ipotesi un valore pari a 0,51 per il genotipo BB vs quelli non-BB (AA + AB), con limiti di confidenza al 95% compresi tra 0,11 e 2,34. Un tale valore di OR potrebbe far ipotizzare che un individuo omozigote BB abbia una resistenza circa 2 volte superiore rispetto ai soggetti con genotipo AA e AB alla brucellosi.

The EU food safety policy aims to ensure a high level of safety at all stages of the production and distribution of food products marketed in the ‘EU, whether produced within the Union or imported from third countries. Sodium chloride, nitric acid, and calcium chloride are the only additives allowed in the production of canned tomatoes. NaCl is a dehydrating agent. Its level must not exceed 3% in canned tomatoes. In official analyses, the Volhard test is employed to measure its levels. Unfortunately, this method is very laborious and does not allow the daily analysis of many samples. In this work, to meet the needs of commodity laboratories, which have to analyze many samples daily, an automated colorimetric test that can determine sodium chloride in canned tomatoes was validated in terms of linearity, the limit of detection and quantification, measured range, accuracy, precision, and recovery. The automatized colorimetric method showed precision, accuracy, and recovery (≥ 95%) statistically equivalent to the Vohlard test. Therefore, it can use for the routine analysis of chlorides in canned tomatoes streamlining analytical laboratories’ work.

Sulfur dioxide is generally used in wine and vinegar production. It is employed to decrease the bacteria' growth, improve the wines' aroma (since it supports the extraction of polyphenols during maceration), protect the wines from chemical oxidation and the musts from chemical and enzymatic oxidation (blocking free radicals and oxidase enzymes such as tyrosinase and laccase). The composition and storage conditions (i.e., pH, temperature, and alcohol levels) affect oenological results. In various countries, competent authorities have imposed legal limits since it can have toxic effects on humans. It is crucial to dose SO2 levels to allow vinegar production and compliance with legal limits. The iodometric titration named "Ripper test" is the legal method used to dose it in vinegar. In this work, an automatized colorimetric test was validated using the international guidelines ISO/IEC (2017) to allow its use instead of the Ripper test. The test reliability was verified on white, red, and balsamic vinegar with low or high SO2 content. The automatized test showed linearity, precision, and reproducibility similar to the Ripper test, but the accuracy parameter was not respected for the vinegar with a low concentration of SO2. Therefore, the automatized colorimetric test can be helpful to dose SO2 in vinegar with high concentrations of SO2.

Salmonella is one of the most common agents of foodborne illness. The genus Salmonella includes two species (Salmonella bongori and S. enterica) and six subspecies (enterica I, salamae II, arizonae IIIa, diarizonae IIIb, houtenae IV, and indica VI), each of which contains multiple serotypes associated with animal and human infections. The aim of the study was to evaluate the presence of Salmonella spp. in carcasses of food-producing animals and foods in southern Italy and the serovar distribution among different sources. From 2011 to 2021, a total of 12,246 foods and 982 samples from animal carcasses were collected and analyzed. The overall percentage of positive samples was 5.84% (N = 773) and a significant increase in prevalence was observed by comparing the years 2011–2015 (257, 3.27%) and 2016–2021 (516, 9.61%; p < 0.05). The highest percentage of positive food samples was observed in “Meat and Meat Products” (N = 327/2,438, 13.41%) followed by “Fish and fishery products” (N = 115/1,915, 6.01%). In carcasses, the highest percentage of positive samples was reported from broilers (N = 42/81, 51.85%) followed by buffalo (N = 50/101, 49.50%) and pork (N = 140/380, 36.84%). After typing, the isolates were assigned to the species S. enterica and to the subspecies: enterica (N = 760, 98.32%), diarizonae (N = 8, 1.03%), salamae (N = 3, 0.39%) and houtenae (N = 2, 0.26%). S. Infantis was the most frequently detected (N = 177, 24.76%), followed by S. Derby (N = 77, 10.77%), monophasic S. Typhimurium (N = 63, 8.81%), S. Typhimurium (N = 54, 7.55%), and S. Rissen (N = 47, 6.57%). By comparing the sampling period 2011–2015 with that of 2016–2021, an increase in the prevalence of S. Infantis and monophasic S. Typhimurium and a decrease of S. Typhimurium were recorded (p < 0.05). Thus, present data suggest that, despite the implementation of national and European control strategies to protect against Salmonella, the prevalence of this pathogen in southern Italy is still increasing and a change of national control programs to protect against Salmonella are necessary.

Antimicrobial peptides (AMPs) are constituents of the innate immune system in every kind of living organism. They can act by disrupting the microbial membrane or without affecting membrane stability. Interest in these small peptides stems from the fear of antibiotics and the emergence of microorganisms resistant to antibiotics. Through membrane or metabolic disruption, they defend an organism against invading bacteria, viruses, protozoa, and fungi. High efficacy and specificity, low drug interaction and toxicity, thermostability, solubility in water, and biological diversity suggest their applications in food, medicine, agriculture, animal husbandry, and aquaculture. Nanocarriers can be used to protect, deliver, and improve their bioavailability effectiveness. High cost of production could limit their use. This review summarizes the natural sources, structures, modes of action, and applications of microbial peptides in the food and pharmaceutical industries. Any restrictions on AMPs’ large-scale production are also taken into consideration.

Bacillus cereus is a spoilage bacterium and is recognized as an agent of food poisoning. Two food-borne illnesses are caused by B. cereus: a diarrheal disease, associated with cytotoxin K, hemolysin BL, non-hemolytic enterotoxin and enterotoxin FM, and an emetic syndrome, associated with the cereulide toxin. Owing to the heat resistance of B. cereus and its ability to grow in milk, this organism should be considered potentially hazardous in dairy products. The present study assessed the risk of B. cereus poisoning due to the consumption of water buffalo mozzarella cheese. A total of 340 samples were analyzed to determine B. cereus counts (ISO 7932:2005), isolates underwent molecular characterization to detect the presence of genes encoding toxins. Eighty-nine (26.1%) samples harbored B. cereus strains, with values ranging from 2.2 &times, 102 to 2.6 &times, 106 CFU/g. Isolates showed eight different molecular profiles, and some displayed virulence characteristics. Bacterial counts and the toxin profiles of isolates were evaluated both separately and jointly to assess the risk of enteritis due to B. cereus following the consumption of buffalo mozzarella cheese. In conclusion, the results of the present study showed that the risk of poisoning by B. cereus following the consumption of this cheese was moderate.

Lactoferrin (Lf) is an iron-binding glycoprotein found in exocrine secretions including milk. High levels of lactoferrin may have a role in the prevention of microbial infection of the mammary gland. In this report we sequenced and characterized goat lactoferrin cDNA and its promoter region in two different breeds of goat. The complete cDNA comprised 2356 nucleotides, including 38 bp at the 5'-UTR and 194 bp at the 3'-UTR. The open reading frame is 2127 bp long and it encodes a mature protein of 689 aminoacids. A total of 19 nucleotide differences, 11 of them being responsible for 8 aminoacid changes, were identified through the comparison with French, Korean and Tibetan goat lactoferrin cDNAs. About 1700 bp of the lactoferrin gene promoter were sequenced. Sequence analysis revealed a non-canonical TATA box, multiple SP1/GC elements, and other putative binding sites for transcription factors, such as NF-kappaB, STAT3 and AP2. Two SNPs were identified, one of which would seem to create a new putative AP2 consensus sequence. The presence of an additional AP2 binding site could be associated with quantitative differences of such protein fraction, which could enhance all the activities related to such protein, and improve mammary gland defence against bacterial infections.

This study was undertaken to detect polymorphisms in the goat and sheep mannose-binding lectin encoding gene (MBL2) and to explore allelic variability of this gene in these two species. The analysis and comparison of the sequences obtained from sheep showed 13 polymorphic sites, six in the promoter and seven in exon 1, four of which were of the missense type. In the goats, 12 polymorphic sites were detected, five intronic, five in the promoter, and one exonic. The exon site was responsible for an amino acid change. Mutations detected at the MBL2 locus in the sheep are of particular interest, being potentially responsible for the alterations of gene expression. A population survey involved 102 ewes of the Sardinian breed and 218 goats of the Nicastrese breed, all reared in southern Italy.

The Mannose Binding Lectin (MBL) is an important factor of natural immunity which acts as a primordial antibody, capable to activate the complement and to link to some sugars (such as mannose) present on the surface of some bacteria as Brucella. In the present study, we report the partial structure of the gene coding for the MBL in sheep and goat as well as the analysis of their promoters. By using as template genomic DNA from leukocytes obtained from individual blood samples we sequenced from -961 nt of the promoter to the 397th nt of the 4th exon of four sheep (EMBL Acc. no. AM933378) and from -978 nt to the 471th nt of the 4th exon of four goats (EMBL Acc. no. AM933377), for a total of 4461 bp and 4515 bp, respectively. By comparing the homologous sequence of the bovine MBL gene (EMBL Acc. no. NC007327), it was possible to determine the size of the exons, similar in both investigated species: 200 bp (exon 1), 117 bp (exon 2), and 69 bp (exon 3). The comparison of the sequences between goat and sheep shows an homology of 92.2%. The differences are due essentially to insertions/deletions at intronic level: the sheep presents with respect to the goat a deletion at the 1st intron of 11 nt, two insertions at the 2nd intron, respectively of 29 and 41 nt, and at the 3rd intron a stretch of eight Guanine in the goat vs. eight Thymine in the sheep. The length of the three introns was 395 bp vs. 385 (intron 1), 1278 bp vs. 1347 (intron 2), and 1028 bp vs. 1019 (intron 3) respectively in goat and sheep. For both species, all the splice junctions follow the common role 5'GT/ 3'AG. The ORF (Open Reading Frame) encodes for 249 amino acid residues, whereas the leader peptide is composed by 19 amino acids. The starting codon (ATG, Methionine) is located between the 10th and the 12th nt of the 1st exon, while the stop codon (TGA) between the 372th and the 374th nt of the 4th exon. While from the comparison of the exonic sequences, 23 SNPs were identified, 10 of which give rise to an amino acidic change. The sequence analysis of the promoter region in sheep shows the presence of the following putative binding sites for transcription factors: TATA-box (ATAAA) and CCAAT-box (CCAAAT) in position -49 and -140 nt, respectively. Furthermore, two glucocorticoid responsive elements (GRE) were identified: in position -765 (AGATCAGA) and -971 (ACTGATCT). The promoter analysis for goat was found to be analogous to that of sheep but it shows the disappearance of the regulatory site GRE (ACTGATCT). Further studies need to be performed in order to verify whether the markers identified in the present study can be associated to the resistance to pathogens such as Brucella melitensis by carrying out suitable test for antimicrobial activity.

The nucleotide sequence of the whole buffalo β-casein encoding gene (CSN2) plus 1,476 nt at the 5' flanking region and 51 nt at the 3' flanking region was determined. The gene is spread over 10.2 kb and consists of 9 exons varying in length from 24 (exon 5) to 498 bp (exon 7) and 8 introns from 92 bp (intron 5) to 22 59 bp (intron 1). Furthermore, highly conserved sequences, mainly located in the 5' flanking region, were found between this gene and the β-casein encoding genes of other species. The comparison between the obtained promoter and exonic regions and buffalo sequences present in EMBL evidenced different polymorphic sites. Finally, 5 interspersed repeated elements (4 in the bovine CSN2 gene) were also identified at 3 different locations of the sequenced region: 5' untranscribed region, intron 1, and intron 4.

The goat CSN1S1 gene has for many years been an excellent model for demonstrating that most of the variability observed in the αs1-casein content in goat's milk is due to the presence of autosomal alleles at a single structural locus . Until now, about 17 alleles associated to at least four levels of αs1-casein expression in milk have been described at the CSN1S1 locus in the domestic goat ( Capra hircus ). The great importance of goat αs1-casein polymorphism is due to its qualitative as well as quantitative implications. In the present work five PCR protocols (PCR-RFLPs, AS-PCR) were set up for rapid genotyping of B1, B2*, B3, B4 and C CSN1S1 alleles, until now detectable only by milk electrophoresis. Application of these protocols, together with previously described methods to identify CSN1S1 01, E, M, F, N and A* ( CSN1S1 A, G, I, H) alleles, allow us to define, at DNA level, the genetic structure of the autochthonous goat reared in the province of Naples for the highest number of possible alleles at this locus . Monitoring of CSN1S1 variability in the Neapolitan goat population indicates a high frequency of low (F, 0.368) and null (N, 0.227) alleles.