Fungi Grown on Farm Waste Turn Into Tough, Tunable Biomaterials

Researchers in South Africa have identified seven non-pathogenic fungal species that can transform agricultural waste into mycelium-based biomaterials with properties that rival, and in some respects exceed, those grown on costly commercial media. The study, published in Applied Microbiology and Biotechnology, systematically screened fungal isolates for their ability to form dense, cohesive mycelial networks and then measured how different growth substrates reshaped the biochemistry, microstructure, and mechanical performance of the resulting materials. The findings suggest that farm residues such as wheat bran are not merely cheap substitutes for refined laboratory media but can actively improve the qualities that matter for real-world applications.

Mycelium-based biomaterials are built by allowing fungal filaments to colonize a substrate, weaving a natural composite that can be dried and shaped into packaging, insulation panels, leather-like textiles, or biomedical scaffolds. The field has attracted intense interest as industries search for renewable alternatives to petroleum-derived plastics and energy-intensive construction materials. Yet translation from laboratory curiosity to scalable product has been hampered by three persistent problems: reliance on a small number of well-known fungal species, resource-intensive cultivation requirements, and a poor understanding of how the choice of substrate dictates the final material properties. The new study tackles all three at once.

Led by Branly-Natalien Nguena-Dongue, Ayodeji Amobonye, and Santhosh Pillai of the Department of Biotechnology and Food Science at the Durban University of Technology, the team screened a range of fungal isolates and selected seven promising candidates: Absidia koreana, Achaetomium globosum, Cubamyces lactineus, Hypoxylon sp., Mucor fragilis, Periconia macrospinosa, and Xylaria berteroi. Each species was cultivated on agro-residues and on various commercial media, allowing the researchers to directly compare how growth substrate influenced mycelial development and the functional characteristics of the derived materials. This paired design is what gives the work its practical punch, because it isolates the substrate as the key experimental variable.

One of the most commercially significant results concerns the growth medium itself. The researchers found that wheat bran agar, a low-cost, minimally refined medium made from an abundant milling by-product, competed favorably with Sabouraud dextrose agar, a standard refined formulation used in mycology laboratories worldwide. Far from being a compromise, wheat bran agar promoted denser and more cohesive mycelial networks. For an industry in which feedstock cost and availability often determine whether a biomaterial process can scale, the demonstration that a crude agricultural residue can outperform a refined laboratory medium is a meaningful economic signal.

To understand why substrates matter at the molecular level, the team applied Fourier transform infrared spectroscopy, a technique that identifies chemical functional groups by how they absorb infrared light. The spectra revealed distinct modulation of polysaccharide-, protein-, and chitin-associated functional groups across the different mycelia, indicating that the growth substrate drives biochemical remodeling within the fungal cell walls. Chitin and fungal polysaccharides are the structural backbone of mycelium composites, so substrate-induced shifts in their abundance and organization translate directly into differences in stiffness, flexibility, and water behavior of the finished material. In effect, the fungus acts as a programmable bioreactor whose output can be tuned by what it is fed.

Scanning electron microscopy added a structural dimension to the story. Mycelia produced on agro-residues showed enhanced hyphal interconnectivity, greater surface roughness, and increased microstructural heterogeneity compared with those grown on refined media. These microscopic features are not cosmetic. Interconnected, roughened hyphal networks create more contact points and mechanical interlocking within a composite, which typically improves cohesion and load transfer. The imaging results thus provide a mechanistic explanation for why waste-grown mycelium can exhibit superior material behavior: the substrate physically shapes the architecture of the living network as it grows.

Among the seven species, Absidia koreana emerged as the standout candidate. It combined strong biomass productivity with remarkable thermal resistance, remaining stable up to 295 degrees Celsius, a figure that opens the door to applications where heat tolerance is essential. Its hyphae were smooth, branched, and thick, with the highest average diameter recorded in the study, measuring 5.02 plus or minus 0.38 micrometers on Sabouraud dextrose agar and 6.99 plus or minus 0.53 micrometers on wheat bran agar. Notably, the hyphae grew even thicker on the waste-derived medium, reinforcing the pattern that agro-residues enhance the structural raw material of the composite.

Mechanical testing quantified just how tunable these materials can be. Dynamic mechanical analysis of mycelium sheets revealed substrate-dependent performance across every metric measured. Xylaria berteroi delivered the highest ultimate stress at 15.54 megapascals, the maximum storage modulus of 2109 megapascals, and the maximum loss modulus of 107.9 megapascals when grown on Sabouraud dextrose agar, while Periconia macrospinosa achieved the highest storage modulus at lower temperature, 1332 megapascals, on the same medium. Damping behavior, which describes a material’s ability to absorb vibration and dissipate energy, peaked at 0.115 at 45 degrees Celsius for Hypoxylon sp. and reached an overall maximum of 0.451 for Xylaria berteroi grown on wheat bran agar. In practical terms, this means manufacturers could select a species-substrate pairing to specify whether a panel should be rigid and load-bearing or compliant and energy-absorbing.

The study also looked downstream at the spent substrates. Elemental analysis of the agro-residues after fungal cultivation indicated that they retain sufficient nutritional value to be reused for further fungal growth in biotechnological industries, a finding with clear implications for circular bioeconomy models. Rather than a single-use input, the waste stream becomes a recyclable platform, reducing both the cost and the environmental footprint of biomaterial production. Combined with the observation that fungal growth structure and protein content improved on agro-waste relative to commercial media, the analysis positions agricultural residues as a strategic resource rather than a disposal problem.

Collectively, the results reframe the relationship between feedstock and product in mycelium technology. The authors conclude that agro-residues are not merely viable substitutes for commercial media but represent superior platforms for tailoring mycelium material properties, a claim backed by spectroscopic, microscopic, thermal, and mechanical evidence. With seven newly validated species, a demonstrated low-cost substrate advantage, a top-performing candidate in Absidia koreana, and a roadmap for matching species to substrate to achieve target mechanical behavior, the study offers the emerging mycelium materials industry both a broader biological toolkit and a more economical path to scale. As brands in fashion, packaging, and construction continue to seek credible sustainable alternatives, research of this kind moves fungal biomaterials from promising novelty toward engineered, specifiable products.

Subject of Research: Bioprospecting fungi for mycelium-based biomaterial production on agricultural waste substrates

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

Article References: Nguena-Dongue, B.-N., Amobonye, A., & Pillai, S. (2026). Bioprospecting selected fungi for mycelium-based biomaterial development: functional characteristics and growth kinetics on agro-wastes. Applied Microbiology and Biotechnology. https://doi.org/10.1007/s00253-026-14020-8

Image Credits: AI Generated

DOI: 10.1007/s00253-026-14020-8

Keywords: mycelium biomaterials, fungal bioprospecting, agro-waste, wheat bran agar, Absidia koreana, solid-state fermentation, thermal stability, dynamic mechanical analysis, circular bioeconomy, renewable materials, chitin, FTIR spectroscopy