Extraction methods, structures characteristics, biological activities, structure-activity relationships,...

Hemerocallis citrina Baroni (H. citrina) is called Daylily in English. H. citrina is mainly used for consumption, but according to records, it has remarkable medicinal properties in folk medicine in multiple countries. In recent years, research results have shown that H. citrina polysaccharides have significant advantages over other small molecule chemicals in developing drugs and health foods. Researchers found that H. citrina polysaccharides showed satisfactory biological activities in anti-diabetes, anti-aging, anti-cancer, anti-oxidant, immune regulation, and promoting the adhesion of probiotics. It is necessary to review the application of polysaccharides from H. citrina in medicine and health food. In addition, there is currently a lack of precise identification methods between H. citrina and Hemerocallis fulva (L.) (H. fulva), and poisoning caused by ingestion is common. Therefore, this article proposes, for the first time, to construct an identification standard system based on the characteristics of polysaccharides. Based on the above reasons, this article reviews and summarizes the research results on the physicochemical properties, biological activities, structure-activity relationships, potential applications, and species identification methods of H. citrina polysaccharides. We hope this article can deepen researchers' and consumers' understanding of H. citrina polysaccharides and provide theoretical support for developing its subsequent products.