Yam polysaccharide extraction, purification, structural features, and biological properties: A review

Yam (Dioscorea opposita Thunb.) is a widely used culinary and medicinal plant rhizome with a long application history. The polysaccharides in yam are important bioactive components. As a natural polysaccharide, yam polysaccharides exhibit strong advantages in terms of physicochemical properties, biological activity, and structural plasticity, making them a research hotspot in the fields of biomedicine and functional foods. However, systematic studies on the stable extraction, structural analysis, modification techniques, and structure-activity relationships of Chinese yam polysaccharide (CYP) remain limited. This review summarizes 124 research publications on CYP over the past 40 years, providing a comprehensive and systematic analysis of the extraction, separation, purification, characterization methods, structural modification, bioactivities, and applications of CYP. It is evident that CYP exhibits diverse biological activities due to its unique structural features, showing broad application potential in the fields of functional foods and pharmaceuticals. However, the structural complexity of CYP, including the variety of glycosidic bonds, differences in molecular weight, and branching structures, poses challenges for in-depth research. Future studies should focus on elucidating the structure-activity relationships, exploring the underlying mechanisms of action, and thereby fully leveraging the natural health benefits of CYP to promote innovation and industrial upgrading in related fields. In conclusion, this systematic review provides scientific guidance for further research and development of Chinese yam polysaccharide.