Mannose‐rich exopolysaccharide from <i>Agaricus sinodeliciosus</i> var. Chaidam: Purification, chemical characterization, and neuroprotective activity

Amyloid β (Aβ) aggregation is a hallmark of Alzheimer's disease (AD). Searching for compounds that attenuate Aβ could uncover novel prevention AD. Herein, an exopolysaccharide (EPS)-2 was purified from the fermentation broth Agaricus sinodeliciosus var. Chaidam. Morphology characterization, circular dichroism spectroscopy, and molecular docking demonstrated EPS-2 inhibited oligomer formation remodeled conformational conversion Aβ1-42, thus reducing cytotoxicity oxidative stress induced by Aβ1-42 oligomers in vitro. Structural characterization revealed neuroprotective with average weight 18 kDa consisted mannose, galactose, small proportion rhamnose, glucose, fucose, ribose, glucuronic acid, galactosamine. Glycosidic linkage nuclear magnetic resonance analysis suggested has backbone →1)-D-Galp-(6→, →1)-D-Manp-(2, 6→, →1)-D-Galp-(2→ →1)-t-Manp branched chains. Therefore, able to block reduced its neurotoxicity, can be developed into potential functional food ingredient AD patients.