  Fungal mycelium, a living network of filamentous threads, thrives on
lignocellulosic waste and exhibits rapid growth, hydrophobicity, and intrinsic
regeneration, offering a potential means to create next-generation sustainable
and functional composites. However, existing hybrid-living mycelium composites
(myco-composites) are tremendously constrained by conventional mold-based
manufacturing processes, which are only compatible with simple geometries and
coarse biomass substrates that enable gas exchange. Here we introduce a class
of structural myco-composites manufactured with a novel platform that harnesses
high-resolution biocomposite additive manufacturing and robust mycelium
colonization with indirect inoculation. We leverage principles of hierarchical
composite design and selective nutritional provision to create a robust
myco-composite that is scalable, tunable, and compatible with complex
geometries. To illustrate the versatility of this platform, we characterize the
impact of mycelium colonization on mechanical and surface properties of the
composite, finding that it yields the strongest mycelium composite reported to
date, and demonstrate fabrication of unique foldable bio-welded containers and
flexible mycelium textiles. This study bridges the gap between biocomposite and
hybrid-living materials research, opening the door to advanced structural
mycelium applications and demonstrating a novel platform for development of
diverse hybrid-living materials.
