Staphylococcus aureus is a major foodborne pathogen due to its capability to produce a wide range of heat-stable enterotoxins. The primary purpose of this research was to characterize S. aureus isolates recovered from mammary quarter milk of mastitic cows and from bulk tank milk produced on Hungarian dairy farms of different sizes. Macrorestriction analysis of chromosomal DNA from S. aureus isolates was performed using the restriction enzyme SmaI followed by pulsed-field gel electrophoresis (PFGE). The prevalence rates of nine S. aureus enterotoxin genes (sea, seb, sec, sed, see, seg, seh, sei, and sej) and of the toxic shock syndrome toxin 1 gene (tst) were determined by multiplex polymerase chain reaction (PCR). The bulk tank milks of 14 out of 20 farms were contaminated with S. aureus at levels of up to 6.0 × 10 3 CFU/ml. Farm size had no significant effect (P N 0.05) on the S. aureus counts in bulk milk. The prevalence rates of penicillin resistance were 88.9% and 20.0% among the S. aureus recovered from mastitic quarter milk and bulk tank milk, respectively. After phenotypic characterization, a total of 59 S. aureus isolates were selected for genotyping. PFGE analysis revealed 22 distinct pulsotypes, including 14 main types and 8 subtypes, at a similarity level of 86%. Only one or two main types were observed on each of the farms tested, indicating a lack of genetic diversity among S. aureus isolates within farms, and there were only two pulsotypes which occurred on more than one farm. The PFGE patterns showed genetic relatedness between the S. aureus strains recovered from quarter milk and bulk milk on two large farms, implying that on farms having a high number of mastitic cows, S. aureus from infected udders may contaminate bulk milk and, subsequently, raw milk products. Sixteen (27.1%) of the S. aureus isolates tested by multiplex PCR were found to be positive for enterotoxin genes, with 15 of them carrying just one gene and one strain carrying two genes (seg and sei). The most commonly detected toxin genes were seb, sea, and sec, whereas none of our isolates possessed the see, seh, sej, or tst genes. On 75% of the dairy farms surveyed, no enterotoxigenic staphylococci were recovered from either mastitic quarter milk or bulk tank milk.

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Aflatoxins (AFs) are among the most harmful fungal secondary metabolites imposing serious health risks on both household animals and humans. The more frequent occurrence of aflatoxins in the feed and food chain is clearly foreseeable as a consequence of the extreme weather conditions recorded most recently worldwide. Furthermore, production parameters, such as unadjusted variety use and improper cultural practices, can also increase the incidence of contamination. In current aflatoxin control measures, emphasis is put on prevention including a plethora of pre-harvest methods, introduced to control Aspergillus infestations and to avoid the deleterious effects of aflatoxins on public health. Nevertheless, the continuous evaluation and improvement of post-harvest methods to combat these hazardous secondary metabolites are also required. Already in-use and emerging physical methods, such as pulsed electric fields and other nonthermal treatments as well as interventions with chemical agents such as acids, enzymes, gases, and absorbents in animal husbandry have been demonstrated as effective in reducing mycotoxins in feed and food. Although most of them have no disadvantageous effect either on nutritional properties or food safety, further research is needed to ensure the expected efficacy. Nevertheless, we can envisage the rapid spread of these easy-to-use, cost-effective, and safe post-harvest tools during storage and food processing.

Aflatoxins (AFs) are toxic secondary metabolites produced mostly by Aspergillus species. AF contamination entering the feed and food chain has been a crucial long-term issue for veterinarians, medicals, agroindustry experts, and researchers working in this field. Although different (physical, chemical, and biological) technologies have been developed, tested, and employed to mitigate the detrimental effects of mycotoxins, including AFs, universal methods are still not available to reduce AF levels in feed and food in the last decades. Possible biological control by bacteria, yeasts, and fungi, their excretes, the role of the ruminal degradation, pre-harvest biocontrol by competitive exclusion or biofungicides, and post-harvest technologies and practices based on biological agents currently used to alleviate the toxic effects of AFs are collected in this review. Pre-harvest biocontrol technologies can give us the greatest opportunity to reduce AF production on the spot. Together with post-harvest applications of bacteria or fungal cultures, these technologies can help us strictly reduce AF contamination without synthetic chemicals.

Pleurotus ostreatus (Jacq. ex Fr.) P. Kumm mushroom contains bioactive compounds with both antimicrobial and prebiotic properties, which are distributed in the mushroom mycelium, fruiting body, and spent substrate. The mushroom is rich in nondigestible carbohydrates like chitin and glucan, which act as prebiotics and support the growth and activity of beneficial gut bacteria, thereby maintaining a healthy balance of gut microbiota and reducing the risk of antibiotic resistance. The bioactive compounds in P. ostreatus mushrooms, including polysaccharides (glucans, chitin) and secondary metabolites (phenolic compounds, terpenoids, and lectins), exhibit antibacterial, antiviral, and antifungal activities. When mushrooms are consumed, these compounds can help preventing the growth and spread of harmful bacteria in the gut, reducing the risk of infections and the development of antibiotic resistance. Nonetheless, further research is necessary to determine the efficacy of P. ostreatus against different pathogens and to fully comprehend its prebiotic and antimicrobial properties. Overall, consuming a diet rich in mushroom-based foods can have a positive impact on human digestion health. A mushroom-based diet can support a healthy gut microbiome and reduce the need for antibiotics.