Encapsulated probiotics as antimicrobial agents: mechanisms and delivery strategies against multidrug-resistant pathogens.

The rapid escalation of antimicrobial resistance (AMR) has rendered many conventional antibiotics ineffective, emphasizing the need for alternative therapeutic approaches. Probiotics have emerged as promising biotherapeutic agents capable of inhibiting multidrug-resistant (MDR) pathogens through diverse mechanisms, including secretion of antimicrobial metabolites (bacteriocins, organic acids, short-chain fatty acids, and hydrogen peroxide), competitive exclusion, quorum-sensing interference, and immune modulation. However, their clinical application is limited by poor stability under environmental and gastrointestinal stressors. Encapsulation technologies, particularly those employing natural biopolymers such as alginate, chitosan, pectin, carrageenan, and gelatin, have substantially improved probiotic viability, storage stability, and site-specific release. Recent advances in semi-synthetic and synthetic carriers, including PLGA, PVA, Eudragit®, and hybrid nanofiber systems, have further enabled controlled delivery and synergistic protection in intestinal, topical, and food-based applications. Collectively, encapsulated probiotics represent a potent strategy for combating AMR by enhancing antimicrobial efficacy and therapeutic consistency. Future research should focus on optimizing encapsulation parameters, integrating multi-strain and synbiotic formulations, and employing multi-omics tools to translate laboratory findings into standardized clinical interventions.