Umami peptides are important taste components of foods. In this study, umami peptides from Hypsizygus marmoreus hydrolysate were purified through ultrafiltration, gel filtration chromatography, and RP-HPLC, and then identified using LC-MS/MS. The binding mechanism of umami peptides with the receptor, T1R1/T1R3, was investigated using computational simulations. Five novel umami peptides were obtained: VYPFPGPL, YIHGGS, SGSLGGGSG, SGLAEGSG, and VEAGP. Molecular docking results demonstrated that all five umami peptides could enter the active pocket in T1R1; Arg277, Tyr220, and Glu301 were key binding sites; and hydrogen bonding and hydrophobic interaction were critical interaction forces. VL-8 had the highest affinity for T1R3. Molecular dynamics simulations demonstrated that VYPFPGPL (VL-8) could be steadily packed inside the binding pocket of T1R1 and the electrostatic interaction was the dominant driving force of the complex (VL-8-T1R1/T1R3) formation. Arg residues (151, 277, 307, and 365) were important contributors to binding affinities. These findings provide valuable insights for the development of umami peptides in edible mushrooms.

Fungal polysaccharides are novel ingredients in functional foods with diverse medicinal properties. Here, a polysaccharide, MSP2‐1, was isolated from Morchella sextelata fruiting bodies and purified using column chromatography. MSP2‐1 (371.5 kDa) is a branched (1 → 4)‐α‐D‐glucan with the O‐6 or O‐3 position occupied by α‐D‐Glcp. Light scattering analysis revealed that MSP2‐1 has a spherical conformation in 0.9% NaCl solution; this was confirmed using transmission electron microscopy. Finally, MPS2‐1 was found to promote proliferation, NO release and cytokine secretion in RAW264.7 cells through a mechanism involving Toll‐like receptor 4. Collectively, these results highlight the potential application of MSP2‐1 as an immunoenhancing compound for hypoimmunity.