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Dairy products play a crucial role in human nutrition as they provide essential nutrients. However, the presence of diverse microorganisms in these products can pose challenges to food safety and quality. Here, we provide a comprehensive molecular characterization of a diverse collection of lactic acid bacteria (LAB) and staphylococci isolated from raw sheep's milk. Whole-genome sequencing, phenotypic characterization, and bioinformatics were employed to gain insight into the genetic composition and functional attributes of these bacteria. Bioinformatics analysis revealed the presence of various genetic elements. Important toxin-related genes in staphylococci that contribute to their pathogenic potential were identified and confirmed using phenotypic assays, while adherence-related genes, which are essential for attachment to host tissues, surfaces in the dairy environment, and the creation of biofilms, were also present. Interestingly, the Staphylococcus aureus isolates belonged to sequence type 5, which largely consists of methicillin-susceptible isolates that have been involved in severe nosocomial infections. Although genes encoding methicillin resistance were not identified, multiple resistance genes (RGs) conferring resistance to aminoglycosides, macrolides, and fluroquinolones were found. In contrast, LAB had few inherently present RGs and no virulence genes, suggesting their likely safe status as food additives in dairy products. LAB were also richer in bacteriocins and carbohydrate-active enzymes, indicating their potential to suppress pathogens and effectively utilize carbohydrate substrates, respectively. Additionally, mobile genetic elements, present in both LAB and staphylococci, may facilitate the acquisition and dissemination of genetic traits, including RGs, virulence genes, and metabolic factors, with implications for food quality and public health. The molecular and phenotypic characterization presented herein contributes to the effort to mitigate risks and infections (e.g., mastitis) and enhance the safety and quality of milk and products thereof. [ABSTRACT FROM AUTHOR]

It is well known that the strong-evidence foodborne outbreaks of human campylobacteriosis are associated with the consumption of raw or incompletely thermally processed poultry meat, whereas broilers act as the main reservoir for Campylobacter species. Campylobacter jejuni and Campylobacter coli are the two main species of campylobacters detected in chicken meat, while they account for almost 90% of the reported cases of campylobacteriosis in humans. Over 80% of these cases are attributed to C. jejuni and about 10% of them are due to C. coli. Therefore, until recently the dominance of C. jejuni against all other Campylobacter spp. isolated from chicken meat samples was well-established and unquestionable. Lately, however, C. coli has been increasingly recovered from chicken meat to such an extent that it is now evident that it often comprises the dominant species among the identified campylobacters in the meat samples. This work attempts for the first time a detailed review of the literature to deepen into this noteworthy epidemiological swift in the prevalence of C. jejuni and C. coli, along with the distribution of Campylobacter spp. in chicken meat. Factors such as the sampling method followed for screening campylobacters in broiler carcasses (e.g., swabs or carcass rinsates, skinned or skinless meat excised samples) and part of the animal carcass from which the sample is obtained (e.g., neck, breast, leg), seasonality of sampling (summer vs. winter) and environmental conditions (e.g., rainfall, relative humidity) at the farm level, the isolation procedure (enumeration or detection) and pathogen identification (biochemical or molecular), the enrichment and plating isolation media (e.g., Bolton vs. Preston broth, charcoal-based vs. chromogenic agars), as well as the biofilm-forming ability of different campylobacters, highlight the multivariate dimension of the phenomenon and are thoroughly discussed in the present review. [ABSTRACT FROM AUTHOR]

The quantification of the effects of salt stress response on thermal inactivation kinetics for exponential-, transition- , and stationary-phase cells of the two Bacillus cereus strains, ATCC 10987 and ATCC 14579 was performed. It was observed that the strain diversity greatly influenced the thermotolerance and survival curvatures and the maximum adaptive salt stress response in exponential-phase was comparable to the physiological state on thermotolerance.