Natural sources of bioactive compounds: recent advances in isolation, functionalization, and health benefits

The enrichment of functional foods with additional bioactive compounds has gained increasing attention due to their potential to prevent chronic diseases and enhance health beyond basic nutrition. This review provides a comprehensive and multidisciplinary analysis of recent advances in the isolation, functionalization, and health-related applications of bioactive compounds derived from natural sources such as fruits, vegetables, legumes, cereals, marine organisms, and microorganisms. Key bioactive classes -such as polyphenols, flavonoids, carotenoids, polyunsaturated fatty acids (PUFAs), bioactive peptides, and organosulfur compounds-are discussed with respect to their chemical properties, natural occurrence, and physiological roles. Emphasis is placed on green extraction technologies (UAE, MAE, SFE) and advanced purification methods (HPLC, GC-MS) that enable selective and sustainable recovery of high-purity bioactives. Functionalization strategies, including nanoencapsulation, polymer conjugation, biotransformation, and stimuli-responsive delivery systems, are examined for their role in improving bioavailability, stability, and targeted release. The review highlights the therapeutic potential of bioactives in modulating oxidative stress, inflammation, metabolic disorders, immune responses, and gut microbiota composition, supported by evidence from preclinical and clinical studies. Finally, current challenges-such as variability in natural sources, regulatory gaps, formulation standardization, and consumer acceptance-are addressed, and future directions are proposed. These include personalized nutrition, AI-guided formulation, and omics-integrated validation, aimed at advancing the development of next-generation functional foods. This review underscores the importance of interdisciplinary collaboration and innovation to unlock the full potential of bioactive compounds in preventive nutrition and global health.