Advances in fucoidan and fucoidan oligosaccharides: Current status, future prospects, and biological applications

Sulfated polysaccharides (SPS) derived from seaweeds are precious bioactive compounds of diverse biological activities. Fucoidan is a complex SPS composed of L-fucose and sulfate groups, can be extracted from brown seaweeds, as well as microbial, insect, plant glycans, and marine invertebrates. It has gained considerable attention due to its anti-inflammatory, anticancer, antiviral, antithrombotic, hypolipidemic, and immune-modulatory properties. Recent research has focused on the extraction and extensive characterization of fucoidan. Its structural complexity, influenced by species, sources, and harvesting conditions, directly influences its bioactivity, with higher sulfation and lower molecular weight enhancing its activity. Interestingly, fucoidan oligosaccharides (FOs) play a critical role in various metabolic processes and hold significant potential in disease diagnostics. This comprehensive review explores the current status of fucoidan research, covering its sources, extraction and purification techniques, structural variations and biological activities. Additionally, we highlight its potential health benefits, providing insights for researchers interested in sulfated polysaccharides.