Design Strategies for Mycelium-Based Composites

Mycelium-based composites (MBC) can be designed utilising a wide range of lignocellulosic substrates and widely distributed versatile ligninolytic fungi. While a wide range of mechanical behaviour has already been reported in the
past 15 years, showing potential to obtain viable products for a variety of uses; no systematic description of the engineering parameters has been established till date. We review carbohydrate-active enzyme (CAZyme) activities of fungal species, lignocellulosic substrate chemical profile at cellular level, wetting characteristics, substrate aggregate and composition characteristics. We identify three principal strategies for designing MBC: supplementation, densification and composition, and discuss them regarding outstanding reports from the state-of-the-art. We report on solid-state fermentation supplements having significant effect on fungal CAZymes activities (e.g. monosaccharide, nitrogen, ash, pH buffer). State-of-the-art designs and process control promote specific enzymatic activities independent of species genomics; systematically investigating supplementation, densification and composition design strategies in the future may lead to both a widening and deepening of the available material qualities, along with a focus on developments around functional poles. Additionally, future reproducibility studies of MBC development reports may both improve the overall market readiness and public adoption of MBC solutions and valorise the wealth of material and design semiotic properties that the versatility and affordability of MBC systems support.