Structural diversity of fungal glucans.

Fungal glucans represent various structurally different d-glucose polymers with a large diversity of molecular mass and configuration. According to glucose anomeric structure, it is possible to distinguish α-D-glucans, β-D-glucans and mixed α,β-D-glucans. Further discrimination could be made on the basis of glycosidic bond position in a pyranoid ring, distribution of specific glycosidic bonds along a chain, branching and molecular mass. Fungal glucans can be chemically modified to obtain various derivatives of potential industrial or medicinal importance. NMR spectroscopy is a powerful tool in structural analysis of fungal glucans. Together with chemolytic methods like methylation analysis and periodate oxidation, NMR is able to determine exact structure of these polysaccharides. Fungal glucans or their derivatives exert various biological activities, which are usually linked to structure, molecular mass and substitution degree.