In the face of mounting environmental crises, the search for sustainable alternatives to traditional materials has led scientists and innovators to fungi. Mycelium, the intricate network of fungal hyphae, has emerged as a promising candidate for creating biodegradable, eco-friendly materials. However, as highlighted in a recent review by Hortense Le Ferrand and her team at Nanyang Technological University (NTU), Singapore, significant barriers still stand in the way of mycelium-based products becoming mainstream. Published in the Journal of Cleaner Production, the study sheds light on the technical, scientific, and market challenges that need to be addressed to unlock the full potential of mycelium.
Image courtesy: University of Kassel
The Promise of Mycelium Based Composites
Mycelium-bound materials are created by growing fungi on lignocellulosic substrates like sawdust or agricultural waste. As the fungus grows, it binds the substrate into a solid, porous composite. These materials are already being used in packaging, insulation, and even decorative elements. But their potential extends far beyond these applications, with ongoing research exploring uses in textiles, furniture, and even electronic casings.
The appeal of mycelium lies in its sustainability. It’s biodegradable, acts as a carbon sink, and valorises waste biomass. However, despite its potential, mycelium-based products face significant technical, scientific, and market challenges that need to be addressed before they can compete with conventional materials like plastics.
(a) Electron micrograph showing the 3-dimensional mycelium network of P. ostreatus. Credit: Eugene Soh. (b) Pictures of commercial products made of mycelium-bound composites. From left to right (top): Industrial packaging by GROWN bio, large gift box by Ecovative, wave acoustic panel by Mogu. From left to right (bottom): Mush Lume Hemi Pendant by GROWN bio and wall panels by Fumo.
Technical Hurdles
One of the primary challenges is scaling up production. Mycelium growth is a slow process, taking 2–4 weeks, and requires precise control over temperature, humidity, and sterility. Large-scale production is further complicated by the formation of a dense fungal skin at the air-substrate interface, which can limit oxygen exchange and lead to inhomogeneous growth in thicker structures.
3D printing offers a potential solution, allowing for the creation of complex shapes with built-in air pathways to facilitate growth. However, this method is time-consuming and not yet suitable for mass production. Additionally, contamination remains a persistent issue, with even minor lapses in environmental control leading to product loss.
Balancing Biodegradability and Durability
Mycelium’s biodegradability is both its greatest strength and its Achilles’ heel. While it’s ideal for short-life products like packaging, its sensitivity to humidity and temperature makes it less suitable for long-term applications. Outdoor use is particularly challenging, with mycelium materials degrading within a month in soil and a few months under weathering conditions.
To address this, researchers are exploring hybrid materials that combine mycelium with synthetic or natural additives to enhance durability. For example, coatings made from beeswax or hydrophobic resins can improve water resistance, while the incorporation of nanomaterials like cellulose nanocrystals can boost mechanical strength. However, these modifications often come at the cost of reduced biodegradability, raising questions about the sustainability of such hybrids.
Scientific Gaps
The field of mycelium-based materials is inherently multidisciplinary, spanning biology, materials science, and engineering. Yet, much remains unknown about the fungi themselves. Most research has focused on a handful of species, such as Ganoderma lucidum and Pleurotus ostreatus, leaving a vast diversity of fungi unexplored. A new project, Chorogram, will attempt to acclerate this aspect of the research and R&D process, by compiling data on all species and methodologies used in the field of mycelium-based composites.
Understanding the growth dynamics of these fungi is crucial. For instance, some species exhibit explorative growth, spreading rapidly to colonise new areas, while others are more exploitative, focusing on nutrient extraction. Harnessing these behaviours could allow for more controlled and efficient production. Additionally, the role of enzymes like laccase and peroxidase in breaking down substrates—and potentially even plastics—offers exciting avenues for future research.
Market Potential and Public Perception
Despite the challenges, mycelium-based products are already finding niche markets in packaging, insulation, and decorative items. However, they remain more expensive than their plastic counterparts, with production times and durability lagging behind. For example, mycelium-based insulation panels can cost up to US$65 for a panel measuring 120 cm × 60 cm × 6 cm, compared to US$43 for synthetic alternatives.
Public perception is another hurdle. While consumers generally appreciate the sustainability of mycelium materials, many are hesitant to bring them into their homes, often due to a lack of understanding or an ingrained mycophobia. Increasing awareness and education about fungi could help shift these attitudes, particularly among environmentally conscious consumers.
The Road Ahead
The future of mycelium-based materials lies in addressing these barriers through interdisciplinary research and innovation. Synthetic modifications and natural enhancements offer pathways to improve performance, while living mycelium materials open up possibilities for self-healing and responsive functionalities.
However, the true potential of mycelium may lie in its ability to inspire a shift in how we think about materials and sustainability. By integrating fungi into our daily lives, we can move towards a more circular economy, where materials are not just consumed but grown, used, and returned to the earth.
References:
Le Ferrand, H. (2024). Journal of Cleaner Production, 450, 141859.
Elsacker et al. (2023). Frontiers in Bioengineering and Biotechnology.
Gan et al. (2022). Scientific Reports.
Soh & Le Ferrand (2023). Materials & Design.