Development and Testing of Mycelium for in-Space Bio-Manufacturing Applications

Mycelia are the root-like structure of fungi such as mushrooms, forming in a mass of branching filaments called hyphae. Currently, mycelium-based composites are being used to develop bio-manufactured material for products such as housing in Namibia [1] and terrestrial architecture applications. While in space the use of mycelium is the subject of a recently funded Phase III proposal from the NASA Institute for Advanced Concepts [2]. Mycelium-based composites are planned to be used on Starlab and other space stations. This paper presents original research into the development of a system to grow and subsequently manufacture mycelium building-blocks, specifically interlocking tiles, for use in a range of spaceflight applications. The system was designed to cultivate Red Reishi mushrooms (Ganoderma Lucidum) and produce a set of interlocking hexagonal tiles within the confines of two (2) Space Shuttle/International Space Station Mid-Deck Locker equivalents, one being used for growth, and the other for manufacturing. These tiles have the capability for interlocking into higher order structures and were produced in multiple quantities within the prototype system through the use of compressing mycelium into bricks and cutting them. While we chose a hexagonal shape, these bricks can ideally be made into almost any shape desired. The produced tiles are then subjected to a range of quantitative materials science testing in laboratories at The Ohio State University, including compressive tests, tensile strength, porosity, and outgassing. Research showed that these mycelium tiles had properties similar to wood, however some tests reflected properties closer to concrete. These tests are designed to fully characterize performance, consistency from batch-to-batch, and suitability for use in spaceflight. In this paper, we present the basic design of our growth and manufacturing system, share results of both the growth and engineering parameters of the produced tiles, articulate potential uses for human spaceflight environments. We conclude with a discussion of future development experiments suitable for low-Earth orbit and Lunar applications to support human exploration in deep space, at the intersection of biology and materials/manufacturing in the context of spaceflight. References [1] marc89908, “Building with Mycotecture: Deep Dive into Fungal Solutions for Sustainable Architecture,” MycoStories, Jun. 10, 2024. https://www.mycostories.com/post/building-with-mycotecture-deep-dive-into-fungal-solutions-for-sustainable-architecture [2] M. Brandić Lipińska et al., “Biological growth as an alternative approach to on and off-Earth construction,” Frontiers in Built Environment, vol. 8, Sep. 2022, doi: https://doi.org/10.3389/fbuil.2022.965145.