Investigation of chemical and biological properties of an acidic polysaccharide fraction from Pleurotus eous (Berk.) Sacc

Pleurotus eous, pink oyster mushroom and functional food, is widely cultivated in Southern India. In this study, we successfully attempted, to isolate a new acidic polysaccharide fraction (PEPA-1a) possessing a molecular weight of 8.926 × 104 Da from the fruiting bodies of Pleurotus eous through ion-exchange and gel-filtration chromatographic techniques. A monosaccharide composition comprising glucose, galactose, rhamnose, mannose, and N-acetyl galactosamine were found to have the corresponding mole percentages of 20.25, 56.75, 3.06, 11.07, and 8.86, respectively. The antioxidant activity was assessed through seven in vitro tests, PEPA-1a showed significant antioxidant activity in a dose-dependent way, with EC50 values stretching from 1.08 to 4.91 mg/mL. Analyses of PEPA-1a towards in vitro anti-tumour showed high activity against HT29 (IC50 = 233.50 μg/mL) and PC3 cells (IC50 = 230.80 μg/mL). The anticoagulant activity was estimated through APTT, PT and TT tests which show effective anticoagulant activity. Also, the congo red analysis revealed the triple-helical structures of carbohydrates. The results indicate that consumption of P eous polysaccharide may be beneficial for health and will serve as an exceptionally accessible natural source for food and pharmaceutical industries.