Ganoderma genus comprises one of the most commonly studied species worldwide, Ganoderma lucidum.
However, other Ganoderma species have been also reported as important sources of bioactive compounds.
Polysaccharides are important contributors to the medicinal properties reported for Ganoderma
species, as demonstrated by the numerous publications, including reviews, on this matter. Yet, what are
the chemical features of Ganoderma polysaccharides that have bioactivity? In the present manuscript, the
chemical features of Ganoderma polysaccharides with reported antioxidant, antitumor and antimicrobial
activities (the most studied worldwide) are analyzed in detail. The composition of sugars (homo- versus
hetero-glucans and other polysaccharides), type of glycosidic linkages, branching patterns, and linkage to
proteins are discussed. Methods for extraction, isolation and identification are evaluated and, finally, the
bioactivity of polysaccharidic extracts and purified compounds are discussed. The integration of data
allows deduction of structure–activity relationships and gives clues to the chemical aspects involved in
Ganoderma bioactivity.