Sulfated modification and biomedical applications of β-glucans: A review

β-glucans, a type of naturally occurring polysaccharide with β-glycosidic linkages, are widely recognized for their immunomodulatory and therapeutic properties, whereas their inherent properties often restrict their further applications. Sulfated β-glucans have emerged as versatile derivatives of β-glucans with enhanced physicochemical properties, driven by the introduction of sulfate groups onto their backbone. They also exhibit novel or improved bioactivities compared to their unmodified counterparts, owing to their modified molecular structures and strengthened interactions with biological targets. This review summarizes recent advancements in sulfation methods, including the chlorosulfonic acid-pyridine method, sulfur trioxide method, and sulfuric acid method, highlighting their mechanisms, advantages, and limitations. Structural characterization techniques and various biomedical applications are discussed to elucidate the sulfation patterns and provide a theoretical basis for further use and development of sulfated β-glucans. Conclusively, sulfation serves as a promising strategy for fine-tuning β-glucan functionalities and expanding their potential in food and pharmaceutical areas.