Marine Bioactive Substances in Precision Nutrient Delivery to the Gut and Advances in Microbiome Regulation: A Narrative Review

Marine bioactive substances exhibit structural diversity and function-specific properties, attracting considerable interest in their potential applications in targeted nutritional delivery to the gut and microbiota regulation. These bioactive components, sourced from seaweed, marine crustaceans, and microorganisms, including polysaccharides, polyphenols, and lipids, demonstrate exceptional biocompatibility and specific recognition capabilities. They serve as an optimal carrier matrix and functional core for developing an efficient, precision-targeted intestinal nutrition delivery system. Research findings demonstrate that optimization via innovative delivery technologies, including nanoencapsulation and polymer microsphere encapsulation, enables marine bioactive substances to navigate various physiological barriers in the gastrointestinal tract effectively. This facilitates targeted, sustained release of nutritional components and enhances bioavailability. Simultaneously, these substances may relieve dysbiosis by modulating the composition of the gut microbiota and the quantity and activity of specific metabolic products, thereby reinforcing intestinal barrier integrity. This narrative review systematically examines the sources and functional attributes of marine bioactive compounds, emphasizing their application strategies in developing targeted delivery systems for the gut and their regulatory effects on gut microbiota. It concludes by delineating future research directions in this field, particularly in optimizing carrier functionalities and clarifying action mechanisms.