Biological Activities of the Polysaccharides Produced in Submerged Culture of Two Edible Pleurotus ostreatus Mushrooms

Exopolysaccharides (EPS) and internal (intracellular) polysaccharides (IPS) obtained from the Pleurotus ostreatus M2191 and PBS281009 cultivated using the batch system revealed an average of between 0.1–2 (EPS) and 0.07–1.5 g/L/day (IPS). The carbohydrate analysis revealed that the polysaccharides comprised 87–89% EPS and 68–74% IPS. The investigation of antioxidant activity in vitro revealed a good antioxidant potential, particularly for the IPS and EPS isolated from PBS281009, as proved by the EC50 value for DPPH, ABTS scavenging activity, reducing power, and iron chelating activity.