Comprehensive investigation on non-volatile and volatile compounds in Auricularia auricula from different regions by UPLC-MS/MS-based metabolomics and GC-IMS

Auricularia auriculata from two regions of China were studied for their metabolite fingerprints, metabolic pathways, and volatile organic compounds (VOCs) using UPLC-MS/MS and GC-IMS techniques in conjunction with multivariate statistical analysis approaches. A total of 881 metabolites were identified by UPLC-MS/MS, of which 39 compounds displayed significant differences. Acetyl-L-carnitine, N-acetyl-L-alanine, PC (18:3(9Z,12Z,15Z)/0:0), 4-fumaryl-acetoacetate, S-2-hydroxybutanedioic acid, and 4-guanidinobutyric acid belonged to the characteristic non-volatile metabolites. The umami-tasted amino acid, essential amino acid was abundant in Heilongjiang and Shaanxi province, respectively. KEGG pathway analysis indicated that differential metabolites were mainly enriched in lipid and amino acid metabolism. The GC-IMS study revealed 64 different types of VOCs, including acids, alcohols, aldehydes, esters, ketones, and other compounds. A. auricula from Shaanxi province was abundant in 2,3-pentanedione, 1-octen-3-one (dimer), 2-acetylfuran, beta-pinene (monomers, dimers) and alpha-pinene. While the primary distinctive VOCs of A. auricula from Heilongjiang province were butyl acetate, methyl acetate and propyl acetate. PCA and OPLS-DA allowed for clear differentiation between the A. auricula samples from the two regions. This research established foundations for investigating potential biomarkers for A. auricula and has important applications values for the creation and implementation of traceability systems within the edible mushroom industry.