Mycelium-based composites (MBCs) have emerged as eco-friendly alternatives, utilizing fungal mycelium as a natural binder for agro-industrial residues. This study focuses on developing an MBC based on abundant waste in Colombia, pith Arboloco (A) (Montanoa quadrangularis), a plant endemic to the Colombian–Venezuelan Andes with outstanding insulating properties, and natural fiber of Kikuyu grass (G) (Cenchrus clandestinus), utilizing Ganoderma lucidum as an agent to form a mycelium network in the MBC. Three formulations, T (100% A), F1 (70% A/30% G), and F2 (30% A/70% G), were evaluated under two different Arboloco particle size ranges (1.0 to 5.6 mm) for their physical, mechanical, and thermal properties. The Arboloco particle sizes did not show significant differences in the MBC properties. An increase in Kikuyu grass proportion (F2) demonstrated superior density (60.4 ± 4.5 kg/m³), lower water absorption (56.6 ± 18.4%), and better compressive strength (0.1686 MPa at 50% deformation). Both mixing formulations (F1–F2) achieved promising average thermal conductivity and specific heat capacity values of 0.047 ± 0.002 W m⁻¹ K⁻¹ and 1714 ± 105 J kg⁻¹ K⁻¹, comparable to commercial insulation materials. However, significant shrinkage (up to 53.6%) and high water absorption limit their scalability for broader applications. These findings enhance the understanding of MBC’s potential for non-structural building materials made of regional lignocellulosic waste, promoting a circular economy in waste management for developing countries.

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.