Abstract: Alginate, a natural anionic polysaccharide derived from brown algae or microorganisms (e. g. , Azotobacter, Pseudomonas), exhibits unique gelling properties and biocompatibility with broad applications in food, pharmaceutical, and material industries. However, limitations including high molecular weight, poor water solubility, and low bioavailability restrict its utilization in high-value biomedicine. Alginate oligosaccharides (AOS)—degradation products of alginate—demonstrate superior potential due to their low molecular weight and enhanced bioactivities, e. g. , antioxidant, immunomodulatory, glucose/lipid regulatory effects. Notably, sodium oligomannate (GV-971) has been developed as a novel therapeutic agent targeting the gut-brain axis for Alzheimer’s disease treatment. This review systematically examines innovative extraction processes for marine algal alginate, alginate lyase development and oligosaccharide preparation and microbial fermentation production of alginate. We anticipate a historic paradigm shift in the alginate industry—from marine resource-dependence to microbial bio-manufacturing. Future research should focus on converging technologies, such as dual-production microbial cell factories, AI-guided fermentation, overcoming industrialization bottlenecks involving cost reduction, standardization, safety risk management; and expanding high-value applications involving precision medicine; sustainable materials; to advance lab-scale innovations toward scalable industrial implementation.
Key words: alginate; alginate lyase; alginate oligosaccharides; microbial alginate; extraction process
（Acta Laser Biology Sinica, 2025, 34(5): 393-400）