Extraction and antioxidant activities of intracellular polysaccharide from Pleurotus sp. mycelium

The extraction conditions of intracellular polysaccharide (IPS) from Pleurotus sp. mycelium in submerged culture were investigated. Four parameters affecting the IPS extraction, ultrasonic treatment time, extraction temperature, extraction time and ethanol concentration, were determined by single factor tests and then optimized by orthogonal experiments. Under the optimized conditions, the extraction rates of IPS of Pleurotus nebrodensis SJ-02, Pleurotus eryngii SI-01 and Pleurotus corncopiae SS-01 were 7.1 ± 0.4%, 7.5 ± 0.3%, and 8.2 ± 0.5%, respectively. The in vitro hydroxyl radical inhibition percentages of IPS of three mushrooms were 32.2 ± 2.8%, 16.1 ± 1.5%, and 38.7 ± 3.1%, respectively. The scavenging effects of IPS on superoxide anion radical and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical were 19.1 ± 1.5%, 16.3 ± 1.3%, 20.3 ± 1.8%, 17.9 ± 1.6%, 16.8 ± 1.4%, and 20.5 ± 1.7%, respectively. The results provide a reference for large-scale production of IPS by Pleurotus sp. in industrial fermentation.