Chemical characterization and structure of exopolysaccharides from submerged culture of new medicinal mushroom from China, Phellinus mori (higher Basidiomycetes).

Two different exopolysaccharides (EPSs) were first time-fractionated from submerged mycelia culture of Phellinus mori (PM) by gel-filtration chromatography: PM-EPS1 and PM-EPS3. Results of compositional analysis using high-performance anion exchange chromatography indicated that both PM-EPS1 and PM-EPS3 were heteropolysaccharides consisting of mannose, glucose, galactose, and rhamnose. Gel permeation chromatography analysis showed that the weight-average molecular mass of PM-EPS1 and PM-EPS3 were 4,990 g/mol and 27,890 g/mol, respectively. Fourier transform infrared spectral analysis of PM-EPS1 and PM-ESP3 revealed prominent characteristic groups corresponding to carbohydrates. 1H and 13C nuclear magnetic resonance spectroscopy analysis indicated that PM-EPS3 had a (1→4)-linked mannopyranosyl backbone, with branches of (1→4)-linked glucosyl residues and (1→3, 4)-linked galactopyranosyl residues. Preliminary activity tests in vitro revealed that the hydroxyl radical scavenging activity and total superoxide dismutase activities of PM-EPS3 obviously increased with an increase in concentration at the range 0.1-2.5 mg/mL.