Advances in anthocyanins: Chemical foundations, synthetic biology, molecular mechanisms, physicochemical properties, and applications in the food industry

Anthocyanins are undergoing a transformative shift from resource-dependent plant extraction to design-led bio-manufacturing. Recent advances in structural modification, notably through glycosylation and acylation, enable precise tuning of their stability, bioaccessibility, and bioactivity. However, major food chemistry-related challenges persist, including poor processing stability under thermal, light, and oxygen exposure, as well as complex matrix interactions in food formulations that compromise color retention and functional longevity. Despite progress, research remains fragmented across chemical, synthetic, mechanistic, and applied domains, hindering integrated development for functional foods, smart materials, and personalized health. This review synthesizes current knowledge on anthocyanin chemistry, biosynthesis, health mechanisms, and industrial applications, with explicit emphasis on food-relevant constraints such as pH-driven degradation, ascorbic acid-induced redox reactions, and protein-polyphenol interactions that affect product shelf life and sensory quality. It highlights how structural engineering supports rational molecular design, while synthetic biology enables gram-scale production via engineered microbial factories. Mechanistically, anthocyanins modulate key pathways such as Nrf2, NF-κB, and AMPK, and interact with the gut microbiota to regulate metabolism and neuroprotection. Their applications now extend from traditional pigments to functional food ingredients and intelligent pH-responsive packaging, yet formulation challenges, including stabilization in beverage systems, protection against thermal processing, and maintenance of bioactivity during storage, remain critical translational bottlenecks. To realize their full potential, future efforts must converge AI-guided design, high-throughput engineering, systems biology, and smart delivery technologies to address bottlenecks in production efficiency, stability, and targeted functionality. Specifically, solving food chemistry challenges such as carrier-assisted stabilization, encapsulation matrix engineering, and predictive modeling of degradation kinetics will be essential for industrial deployment. Ultimately, anthocyanins are poised to serve as pivotal molecules linking sustainable biomanufacturing with precision nutrition and next-generation food systems.