Structural and functional insights into β-D-glucans from mushrooms: A comprehensive review

Mushroom-derived β-D-glucans are structurally diverse bioactive polysaccharides with promising applications in functional foods, nutraceuticals, and health-related products. Despite extensive research, establishing clear structure-function relationships remains a major challenge due to the intrinsic complexity of these polymers and the lack of standardized characterization approaches. Therefore, this review provides a critical overview of methodologies used for the characterization of mushroom β-D-glucans, with particular emphasis on advanced analytical strategies for purification assessment and structural elucidation, including nuclear magnetic resonance (NMR), methylation analysis, and complementary physicochemical methods. We discuss the limitations of commonly used approaches, particularly the risks associated with relying on isolated or limited analytical methodologies, and propose an integrated workflow for the structural characterization of mushroom-derived β-D-glucans. Furthermore, we systematically correlate key structural features, such as molecular weight, branching degree, and solubility, with reported biological effects, providing a conceptual framework to guide future investigations. By integrating chemical, physicochemical, and biological perspectives, this review aims to improve reproducibility, minimize misinterpretation, and support the rational development of β-D-glucan-based applications. Overall, this work provides critical insights and practical recommendations to advance the understanding and translational potential of mushroom-derived β-D-glucans.