Volatilomic Study of the Chemodiversity of Metabolites in Wild Macromycetes of the Lower Montane Humid Forest.

Colombia's rich biodiversity highlights the potential for chemical exploration of plants, animals, and fungi. Fungi play essential ecological roles in organic matter degradation, nutrient cycling, and symbiotic interactions. Fungal volatilomics has emerged as a valuable approach for characterizing volatile organic compounds (VOCs) with potential biotechnological, pharmaceutical, and environmental applications. This study aimed to characterize the volatile organic compounds (VOCs) naturally emitted by wild macromycete species collected in the Botanical Garden of the University of Caldas (Manizales, Colombia), contributing to the chemical characterization of their volatilome and providing a basis for future studies on fungal biomarkers and bioactive metabolites. VOCs were extracted using static and dynamic headspace solid-phase microextraction (HS-SPME, SHS-SPME, and DHS-SPME) with PDMS/DVB/CARB fibers and Tenax tubes. Samples were analyzed both in situ and under controlled laboratory conditions using GC-MS for qualitative identification. More than 120 VOCs were identified, including alcohols, ketones, terpenoids, aromatic compounds, and branched alkanes. The volatilomic profiles differed among fungal species and according to the extraction methodology employed, highlighting compounds such as 1-octen-3-ol, 3-octanone, D-limonene, caryophyllene, and 2,6-di-tert-butyl-4-methylphenol. Multivariate statistical analyses and metabolic pathway annotation revealed distinct volatilomic patterns and suggested associations with lipid metabolism, fatty acid biosynthesis, and terpenoid biosynthesis. The chemical diversity identified demonstrates that tropical wild macromycetes constitute an important source of structurally diverse volatile metabolites. Furthermore, the complementary use of SHS-SPME, DHS-SPME, and laboratory HS-SPME expanded VOC coverage, providing a comprehensive volatilomic dataset that may support future applications in fungal chemotaxonomy, bioprospecting, ecological studies, and the discovery of candidate bioactive compounds.