Establishment of the basidiomycete Fomes fomentarius for the production of composite materials

Abstract

Background Filamentous fungi of the phylum Basidiomycota are considered as an attractive source for the biotechnological production of composite materials. The ability of many basidiomycetes to accept residual lignocellulosic plant biomass from agriculture and forestry such as straw, shives and sawdust as substrates and to bind and glue together these otherwise loose but reinforcing substrate particles into their mycelial network, makes them ideal candidates to produce biological composites to replace petroleum-based synthetic plastics and foams in the near future. Results Here, we describe for the first time the application potential of the tinder fungus Fomes fomentarius for lab-scale production of mycelium composites. We used fine, medium and coarse particle fractions of hemp shives and rapeseed straw to produce a set of diverse composite materials and show that the mechanical materials properties are dependent on the nature and particle size of the substrates. Compression tests and scanning electron microscopy were used to characterize composite material properties and to model their compression behaviour by numerical simulations. Their properties were compared amongst each other and with the benchmark expanded polystyrene (EPS), a petroleum-based foam used for thermal isolation in the construction industry. Our analyses uncovered that EPS shows an elastic modulus of 2.37 ± 0.17 MPa which is 4-times higher compared to the F. fomentarius composite materials whereas the compressive strength of 0.09 ± 0.003 MPa is in the range of the fungal composite material. However, when comparing the ability to take up compressive forces at higher strain values, the fungal composites performed better than EPS. Hemp-shive based composites were able to resist a compressive force of 0.2 MPa at 50% compression, rapeseed composites 0.3 MPa but EPS only 0.15 MPa. Conclusion The data obtained in this study suggest that F. fomentarius constitutes a promising cell factory for the future production of fungal composite materials with similar mechanical behaviour as synthetic foams such as EPS. Future work will focus on designing materials characteristics through optimizing substrate properties, cultivation conditions and by modulating growth and cell wall composition of F. fomentarius, i.e. factors that contribute on the meso- and microscale level to the composite behaviour.

Mechanical, Physical, and Chemical Properties of Mycelium-Based Composites Produced from Various Lignocellulosic Residues and Fungal Species

“…The development of biomaterials, which is largely based on lignocellulosic residues, has various potential advantages that include their diminished environmental impact and the utilization of renewable resources [16]. Mycelium-based composites (MBCs) are a type of biomaterial that holds great potential for the goal of using agricultural residues in specifically beneficial ways and in the broader embrace of fungal biotechnology [17]. Saprobic fungi can degrade lignocellulosic residues into nutrients through certain bio-fabricated processes wherein their mycelia networks can effectively combine substrate particles together [18].…”

Connecting materials sciences with fungal biology: a sea of possibilities

“…The research articles by Elsacker et al [ 2 ], Chen et al [ 3 ] and Pohl et al [ 4 ] discuss the potentials of the white-rot fungi Trametes versicolor and Fomes fomentarius for the fabrication of fungal composite materials and highlight possibilities for their improvement and even use in 3D printing (additive manufacturing) when biopolymers, such as alginates or cellulose, are added as binders. Vandelook et al [ 5 ] contributed with a primer which features the endless application possibilities of pure fungal mycelium from Ganoderma , Fomes , Trametes , Pycnoporus , or Perenniporia spp.…”

The complex structure of Fomes fomentarius represents an architectural design for high-performance ultralightweight materials

“…Unexpectedly, the fruiting bodies of F. fomentarius and their material properties have received the attention of the scientific community only very recently ( 18 , 19 ), despite having great potential for producing biodegradable leather-like materials from lignocellulosic biomass. Furthermore, to our knowledge, there are no widely accepted explanations for the specific mechanical roles of the different structural elements found in the fruiting bodies of bracket fungi, although they could serve as a source of inspiration for the production of multifunctional ultralightweight materials with properties that could potentially surpass natural materials in the future.…”