Bioprospecting selected fungi for mycelium-based biomaterial development: functional characteristics and growth kinetics on agro-wastes

Abstract

Despite the potential of mycelium-based biomaterials as renewable alternatives to synthetic materials in the biomedical, construction, fashion, and packaging industries, their translation into scalable applications is hindered by reliance on a limited number of species, resource-intensive cultivation, and poorly understood substrate–property dynamics. Thus, we systematically screened various fungal isolates, resulting in the identification of seven non-pathogenic species with strong potential as biomaterials, viz., Absidia koreana , Achaetomium globosum , Cubamyces lactineus , Hypoxylon sp., Mucor fragilis , Periconia macrospinosa , and Xylaria berteroi . Subsequently, the fungi were cultivated on agro-residues and various commercial media to assess the effects of growth substrates on mycelial development and material properties. Quantitative analyses revealed that wheat bran agar (WBA) media competed favourably with Sabouraud dextrose agar (SDA), promoting denser, more cohesive mycelial networks despite their lower refinement and lower cost. Fourier transform infrared spectroscopy revealed distinct modulation of polysaccharide-, protein-, and chitin-associated functional groups, suggesting substrate-driven biochemical remodelling across different mycelia, while scanning electron microscopy showed enhanced hyphal interconnectivity, surface roughness, and microstructural heterogeneity in mycelia produced on agro-residues. Notably, A. koreana was identified as the most promising of all the evaluated fungi based on biomass productivity and thermal resistance (295 °C), as well as its smooth, branched, and thick hyphae network with the highest average diameter (5.02 ± 0.38 µm on SDA and 6.99 ± 0.53 µm on WBA). The dynamic mechanical analysis highlighted the effect of the growing substrates on the mechanical performance of the derived mycelium sheet, with the highest ultimate stress of 15.54 MPa, maximum storage modulus of 2109 MPa, and the maximum loss modulus of 107.9 MPa for X. berteroi on SDA, the highest storage modulus at lower temperature of 1332 MPa for P. macrospinosa on SDA, while the highest damping behaviour at lower temperature (45 °C) of 0.115 for Hypoxylon sp., and the maximum damping behaviour of 0.451 for X. berteroi on WBA. Finally, elemental analysis of agro-residues indicates their reusability for sustainable fungal cultivation in biotechnological industries. Collectively, these findings demonstrate that agro-residues are not merely viable substitutes for commercial media but represent superior platforms for tailoring mycelium material properties. • Improvement of fungal growth structure and protein content on agro-waste relative to commercial media. • Thermal stability of Absidia koreana mycelium, a top biomaterial candidate. • Compositional analysis indicates the reusability of agro-wastes as growth substrates.