Engineering Biohybrid Mycelium Fibers through Hierarchical Structuring and Biomineralization

Summary Driven by the persistence of microplastics and an overdependence on non-renewable sources, mycelium materials have emerged as alternatives to traditional materials, owing to their sustainable production and versatility. Engineered living materials, composite material systems incorporating biological components to enable function, possess desirable regenerative properties but have yet to be fully applied due to their lack of strength versus synthetic or natural materials. We leverage two strategies used by nature to generate mechanical strength: structural hierarchy and biomineralization. We extrude a bioink composed of alginate and a modified strain of the fungus Aspergillus niger capable of silica mineralization, and modulate the morphology by the growth and processing conditions. Mineralization results in significantly stronger and stiffer dried fibers. We demonstrate their potential as textile materials through twisting and braiding to significantly increase the fracture strain. Our results show that mycelium morphology and mechanics can be tuned through mineralization, growth conditions, and processing.