Dynamic VOC fingerprinting and mechanistic exploration of medicinal edible fungus Inonotus hispidus: A combination of HS-GC-IMS/MS multivariate analysis and network-based pharmacology.

Inonotus hispidus (IH) is a species of traditional edible and medicinal fungus consumed in China, known for its anti-inflammatory, antioxidant, and anticancer pharmacological effects. IH has garnered widespread attention due to its therapeutic potential in clinical applications. However, despite its widespread use, comprehensive studies on its volatile chemical constituents and pharmacological mechanisms remain limited. In this study, the volatile components of IH at three growth stages (budding, mid-ripe, and full-ripe) were analyzed using headspace-gas chromatography-mass spectrometry (HS-GC-MS) and headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS). Network pharmacology was further employed to investigate the mechanisms underlying its anti-inflammatory, antioxidant, and anticancer effects. Results showed that 20 and 37 volatile compounds were identified by HS-GC-MS and HS-GC-IMS, respectively, with alcohols and ketones being the predominant classes. Principal component analysis (PCA) and partial least squares-discriminant analysis (PLS-DA) revealed distinct separations among the three growth stages, with 16 key volatile organic compounds (VOCs) identified (VIP > 1). Relative odor activity value (ROAV) analysis highlighted 3-octanone, 3-methyl-1-pentanol, and 3-octanol as key flavor compounds contributing to earthy, mushroom, roasted, and grassy aromas. In the network pharmacology study, 34 compounds interacting with 59 common targets were identified. Protein-protein interaction (PPI) network analysis identified PTGS2, EGFR, ESR1, NFKB1, HIF1A, and STAT3 as core hubs. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses elucidated the molecular mechanisms of IH's pharmacological effects. This study fills the research gap in IH's volatile components and deciphers their molecular mechanisms, providing a scientific foundation for quality control and further pharmacological investigations.