Comparative Metabolomics Reveals the Adaptive Strategy of White Auricularia cornea to Bamboo Substrate Variation

To address the "fungus-forest conflict" in the edible mushroom industry and the challenge of resource utilization for bamboo substrate waste, this study focused on white Auricularia cornea, and cultivation systems were established with bamboo substrate replacing wood chips at ratios of 0%, 18%, 38%, 58%, and 78%. By integrating liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis with agronomic trait measurements, the study elucidated the metabolic adaptation mechanisms of the substrate. Results indicated that white A. cornea could grow normally in all bamboo substrates, with the 58% bamboo substrate replacement group (D_58) demonstrating the most optimal overall performance. The mycelial growth rate reached 3.55 ± 0.24 mm/d, and the growth period was the shortest (86.2 d), balancing growth efficiency with cost advantages. Metabolomics detected 3779 metabolites, primarily amino acids and their derivatives (42.2%) and organic acids (35.54%). Compared to the control group, each treatment group exhibited 104-528 upregulated and 192-630 downregulated differential metabolites, with 93 shared differential metabolites and numerous unique markers. KEGG pathway enrichment analysis revealed that varying bamboo substrate ratios shaped growth adaptation strategies by regulating core pathways such as nucleotide metabolism and ABC transporters. This study established the feasibility and optimal formulation of bamboo substrate substitution, elucidated the substrate-metabolite-phenotype linkage mechanism, and provided theoretical foundations and practical references for high-quality cultivation of white A. cornea and sustainable development through "substituting bamboo for wood" to reduce carbon emissions.