Sparassis latifolia is a rare edible mushroom with many pharmacological activities. Active screening found that the crude polysaccharide from this mushroom (SLP) exhibited noticeable gastroprotective effects. However, it remains unclear regarding the underlying regulatory mechanism of the gastroprotective effects of SLP. A novel polysaccharide SLP-2 was purified from the fruiting bodies of S. latifolia, and characterized using FT-IR, HPAEC, SEM, SEC–MALLS-RI, methylation, and NMR analysis. Structural characterization revealed that the backbone of SLP-2 was mainly composed of → 4)-α-D-Glcp-(1 → , → 3)-α-D-Glcp-(1 → and → 3,4)-α-D-Glcp-(1 → . The branched chain primarily consisted of β-D-Glcp-(1 → linked to the sugar residue → 3, 6)-β-D-Glcp-(1 → at the O-6 position and → 3,4)-β-D-Glcp-(1 → at the O-4 position. Physiological experimental results demonstrated that SLP-2 effectively protected GES-1 cells against ethanol-induced damage by suppressing intracellular ROS levels and cell apoptosis while elevating the activities of SOD and CAT enzymes. Furthermore, transcriptome analysis revealed molecular mechanisms underlying the gastroprotective effect of SLP-2, with KEGG enrichment suggesting associations with ferroptosis, TNF, PI3K–Akt, MAPK and IL-17 signaling pathways. These findings provide a technological foundation for valuable utilization of S. latifolia and emphasize the potential application of SLP-2 in repairing gastric mucosal injuries. Graphical Abstract

Stropharia rugosoannulata is a widely cultivated edible mushroom known for its nutritional value and umami flavour. Electronic tongue technology and metabolomics revealed that glutamic acid (Glu) and aspartic acid (Asp) levels were positively correlated with umami in the fruiting body developmental stages. Subsequent investigations found that overexpression of SrCS within the TCA cycle resulted in decreased levels of Glu and Asp. Integrating TF-gene-metabolite network modelling with experiments identified SrELT1 as a transcriptional regulator of SrCS. Different temperatures, cultivation substrates and genetics significantly impacted SrELT1 and SrCS expression, thereby affecting Glu and Asp synthesis. The findings suggest that increased Citrate synthase (CS) activity channelled citrate into glycolysis and oxidative phosphorylation without excessive accumulation; in contrast, decreased CS activity shifted metabolism toward the production of metabolites like Glu and Asp. This study provides insights for enhancing the umami of S. rugosoannulata, thereby substantially increasing its market competitiveness in the premium food segment.