Hyaluronic acid: biological functions, production strategies, and clinical applications

Hyaluronic acid (HA) is a naturally occurring glycosaminoglycan with broad biological significance and extensive applications in medicine, biotechnology, and aesthetics. This review provides a comprehensive overview of HA, focusing on its molecular structure, physicochemical properties, and biological functions that underpin its diverse therapeutic potential. We discuss conventional and emerging HA production strategies, including animal-derived extraction, microbial fermentation, and innovative cell-free enzymatic manufacturing approaches, highlighting their advantages and limitations. Furthermore, the manuscript systematically explores the biomedical and clinical applications of HA in areas such as skincare, osteoarthritis management, wound healing, ophthalmology, tissue engineering, drug delivery systems, and 3D bioprinting. Particular emphasis is placed on the influence of molecular weight and HA-receptor interactions on biological activity and therapeutic outcomes. Finally, current challenges and future perspectives in HA research and production are discussed, positioning this review as a foundational resource for researchers seeking to explore and expand the applications of hyaluronic acid.