Rheological properties and antitumor activity of schizophyllan produced with solid-state fermentation.

Schizophyllan (SPG) was produced by the fungus Schizophyllum commune under solid-state fermentation conditions in this study. SPG was physically characterized and its rheological properties and antitumor effects on S180 tumors in vivo were evaluated. SPG is a neutral polysaccharide with three main fractions, and the major fraction comprises 55.5%, with an average molecular weight 4.65 × 10(7) Da. Steady shear rheological measurements showed the typical pseudoplastic flow behavior of SPG at the experimental concentrations. The power law model was used to fit the shear curves of SPG and both its viscosity and consistency indices changed regularly as the concentration increased. SPG solution showed different viscoelastic behaviors at different concentrations: typical viscoelastic behavior was observed at lower concentrations, whereas solid-like behavior was observed at higher concentrations. Experimental doses of SPG exerted extreme antitumor effects in vivo, and the maximum inhibition rate was almost 70%.