Preparation of newly identified polysaccharide from Pleurotus eryngii and its anti‐inflammation activities potential

Abstract The anti‐inflammatory effects of two newly identified Pleurotus eryngii polysaccharides (WPEP, NPEP) were determined in lipopolysaccharide (LPS)‐stimulated RAW264.7 macrophages in this study. Characterization analysis revealed that molecular weights of WPEP and NPEP were 167 and 274 kDa, and were mainly composed of glucose with β‐type glycosidic linkages. WPEP and NPEP could significantly inhibit LPS‐induced inflammatory responses by regulating the production of NO, Protaglandin E2 (PGE 2 ), Interleukin‐1β (IL‐1β), Tumor necrosis factor‐α (TNF‐α), and Interleukin‐6 (IL‐6). This was through the blocking of the activation of Mitogen‐activated protein kinase (MAPK) pathway by inhibiting phosphorylation of p38, extracellular regulation of protein kinases 1/2, and stress‐activated protein kinase/jun aminoterminal kinase. Moreover, WPEP and NPEP inhibited NF‐κB signaling by reducing nuclear translocation and phosphorylation of p65. Overall, our results, for the first time identified two P. eryngii polysaccharides and demonstrated the related anti‐inflammatory effects, which indicated the favorable potential of P. eryngii polysaccharide as specific functional foods. Practical Application This study prepared and characterized newly identified Pleurotus eryngii water‐soluble polysaccharide fractions and elucidated the nutritional benefits, mainly the immune response related to anti‐inflammatory activities by utilizing lipopolysaccharide (LPS)‐stimulated RAW264.7 cells. Collectively, results of this study suggested that the P. eryngii polysaccharide fractions could be considered as potential candidates for exploration in the development of new immunomodulatory agent or functional supplementary foods.