Fucosylated human milk oligosaccharides (FHMOs), a pivotal subclass of human milk oligosaccharides, are essential for neonatal health, performing diverse core physiological functions: prebiotic activity, pathogen adhesion inhibition, immune modulation, intestinal barrier integrity maintenance, and neurocognitive development promotion via the gut-brain axis. Representative FHMOs including 2'-fucosyllactose (2'-FL), 3-fucosyllactose (3-FL), difucosyllactose (DFL) and lacto-N-fucopentaose I (LNFP I) have obtained safety certification from the U.S. Food and Drug Administration and been commercially utilized in infant formula as functional additives. This review focuses on the structural classification and diversity of FHMOs. It comprehensively summarizes the molecular mechanisms underlying their multifunctional roles, systematically elaborates on core biomanufacturing strategies including enzymatic synthesis and microbial metabolic engineering, and reviews advances in their safety assessment, global regulatory status and commercial applications. Aiming at the industrial bottlenecks including low synthesis efficiency of structurally complex FHMOs and urgent demand for key enzyme optimization, this review analyzes the feasibility and development trends of various biological preparation methods, summarizes the cutting-edge interdisciplinary research progress, and prospects the future research directions and potential technological breakthroughs of FHMOs. This review is expected to provide a comprehensive theoretical reference and practical guidance for the in-depth research, development and industrialization of FHMOs.
