Casein and Casein-Derived Peptides: Antibacterial Activities and Applications in Health and Food Systems

The growing threat of antimicrobial resistance has intensified the search for alternative strategies to conventional antibiotics and preservatives. Casein-derived antimicrobial peptides (CDAMPs), generated through proteolysis, exhibit potent activity against a broad spectrum of pathogens, including antibiotic-resistant strains, revealing strong potential as natural preservatives and therapeutic agents in food and medical applications. Furthermore, casein can be an ideal source for peptide production in these sectors due to its abundance, disordered structure, which enhances enzymatic cleavage, and its amino acid profile, which favors bioactivity. Nonetheless, there is limited literature addressing real-life applications in veterinary medicine, food safety, and public health. This review provides a structured synthesis of current knowledge on the antibacterial properties of CDPs. We classify the main types of these peptides, describe their production methods, and summarize their mechanisms of action against Gram-positive and Gram-negative bacteria. Furthermore, we examine their potential applications in clinical, veterinary, and food-related contexts, and discuss key aspects related to delivery systems, safety, and regulatory considerations. Overall, our findings highlight the potential of CDPs in addressing antimicrobial resistance, reducing antibiotic use in livestock and humans, and contributing to sustainable food safety and functional food production.