Sulfation of the extracellular polysaccharide produced by the edible mushroom Pleurotus sajor-caju alters its antioxidant, anticoagulant and antiproliferative properties in vitro

An extracellular polysaccharide (PN) composed of mannose:3-O-methyl-galactose:galactose:glucose (44.9:16.3:19.8:19) was obtained from Pleurotus sajor-caju. This polymer showed specific antioxidant activities such as total antioxidant capacity, superoxide radical scavenging, reducing power and ferric chelating, but it did not possess anticoagulant or antiproliferative activities. Through chemical modification of PN, the hydroxyl radical scavenging and reducing power activities of PN increased. A derived sulfated polysaccharide of PN, with a DS of 0.17 and named PS, was obtained using a sulfuric acid/n-propanol method. The sulfation was confirmed by electrophoresis, NMR and FT-IR. In addition, PS prolonged the time of coagulation in a concentration-dependent manner in aPTT test. The antiproliferative effect against HeLa cells was time dependent; after 72 h, the inhibition rate of PS (1.0 mg/mL) was approximately 60%. PS demonstrated promising antioxidant, antiproliferative and anticoagulant properties and has been selected for further studies.