Circular and scalable leather alternatives from fungal fruiting bodies

Fungal leather alternatives, intended to imitate animal leather, are popular with fashion designers. Most fungal leather alternatives rely on ‘as-grown’ mycelium networks, which are time-intensive to grow and difficult to scale. We present a leather alternative designed for scalability, utilising mushroom residues and papermaking methods. Flexible chitin-glucan sheets were produced from Agaricus bisporus mushrooms with tensile strengths up to 20 MPa, values approaching those of synthetic and bovine leather (∼13 MPa and 10–31 MPa, respectively), and strains-to-failure of 16–18% (compared to 15–60% and 31–69%, respectively). Sheet aesthetics and mechanical properties were tailored through modified fungal pulp extraction, dyeing, and reinforcement with cellulose-based fibres to achieve tear strengths comparable to bovine leather (104–107 N/mm compared to 42–106 N/mm). Mushroom residue-based sheets demonstrated a solution aligned with the principles of circularity, converting underutilised by-products into wearable garments to reduce waste and resource use in the fashion and textile industries.