Polysaccharides from bamboo-associated edible and medicinal fungi: Structural features, bioactivities, and evidence for structure-activity relationships.

Polysaccharides from edible and medicinal fungi have been widely investigated, but the relationships among fungal ecological context, polysaccharide characteristics, and structure-activity associations (SARs) remain insufficiently resolved. This review examines bamboo-associated edible and medicinal fungi (BEMF), defined as fungi associated with bamboo, bamboo-derived substrates, or bamboo-forest habitats. We summarize reported polysaccharide characteristics, including molecular weight, monosaccharide composition, chemical modifications, glycosidic linkages, branching, conformation, and biological activities. Comparisons are interpreted cautiously because studies often differ in fungal species or strain, substrate, cultivation conditions, extraction and purification procedures, structural analyses, and bioactivity assays. Accordingly, observed differences are considered primarily hypothesis-generating rather than evidence of a bamboo-specific ecological effect. Reported antioxidant, immunomodulatory, antitumor, gut microbiota-modulating, and metabolic activities are evaluated using a three-level framework distinguishing correlative observations, SAR associations, and evidence approaching causal mechanisms. The proposed "niche → structure → activity" relationship is presented as a testable hypothesis. Standardized isogenic-strain comparisons using bamboo-derived and non-bamboo substrates are proposed for future validation. Artificial intelligence applications and key methodological gaps are also discussed.