Exploring the Mechanisms of Amino Acid and Bioactive Constituent Formation During Fruiting Body Development in Lyophyllum decastes by Metabolomic and Transcriptomic Analyses

<i>Lyophyllum decastes</i>, a common edible mushroom, is prized for its exceptional taste and rich nutritional composition. The concentrations of amino acids and polysaccharides in the fruiting body exhibited a dynamic increase throughout development, reaching their highest levels in the maturation stages, with values of 45,107.39 μg/g and 13.66 mg/g, respectively. Integrated metabolomic and transcriptomic analyses uncovered dynamic metabolites changing during the transition from vegetative growth to reproductive development. Several differentially expressed genes (DEGs) and differentially accumulated metabolites (DAMs) were identified, associated with secondary metabolite, amino acid, and carbohydrate metabolism. The shift in metabolites was linked to key nutrient synthesis, explaining the abundant production of amino acids and polysaccharides at maturity. Our results provide novel insights into the developmental biology of <i>L. decastes</i>, demonstrating that this mushroom is a valuable source of bioactive compounds and contributing to the optimization of cultivation strategies, as well as improving research into its application as a functional food and nutraceutical source.