Anthocyanin‐Loaded Nanocarriers for Gut Microbiota Modulation: Mechanisms, Translational Challenges, and Future Perspectives

Anthocyanins are bioactive flavonoids with recognized capacity to modulate gut microbiota composition, microbial metabolism, and host physiological signaling. However, their nutraceutical and therapeutic applications are constrained by poor physicochemical stability, limited bioavailability, and rapid gastrointestinal degradation. Nanotechnology‐based delivery systems have emerged as promising strategies to enhance anthocyanin protection, regulate release kinetics, and improve targeted colonic delivery. This review critically examined anthocyanin‐loaded nanocarriers, including polymeric, lipid‐based, protein‐based, polysaccharide‐based, and hybrid systems, with particular emphasis on their mechanistic interactions with the gut microbiota. Key pathways discussed include microbiota‐responsive release, microbial biotransformation, short‐chain fatty acid production, intestinal barrier modulation, and immune signaling. Current evidence from in vitro and animal studies suggests that nanoencapsulation improves anthocyanin stability, microbial accessibility, and colonic retention; however, robust human clinical validation remains limited. Major translational barriers include incomplete mechanistic understanding, lack of standardized dose–response frameworks, insufficient long‐term safety assessment, regulatory uncertainty, and industrial scalability challenges. Future progress will require standardized methodologies, multiomics integration, physiologically relevant translational models, rigorous clinical investigation, and harmonized regulatory frameworks to advance anthocyanin‐loaded nanocarriers toward evidence‐based microbiota‐targeted nutraceutical and precision nutrition applications.