New, ‘Living’ Building Material Made From Fungi and Bacteria Could Pave the Way to Self-Healing Structures Researchers are developing the biomaterial as a more environmentally friendly alternative to concrete, but any wide-scale use is still far away Microscopic images of the bacteria and mycelium scaffolds. The circles indicate the likely presence of S. pasteurii bacteria. Viles, Ethan et al., Cell Reports Physical Science 2025 Concrete is a crucial construction material. Unfortunately, however, producing it requires large amounts of energy—often powered by fossil fuels—and includes chemical reactions that release carbon dioxide. This intensive process is responsible for up to 8 percent of humanity’s carbon dioxide emissions. As such, finding more sustainable building materials is vital to lessening our global carbon footprint. And to help achieve this goal, scientists are studying methods that might replace concrete with biologically derived materials, or biomaterials for short. Now, researchers have developed a building material made of mycelium—the tubular, branching filaments found in most fungi—and bacteria cells. As detailed in a study published last week in the journal Cell Reports Physical Science, the living bacteria survived in the structure for an extended amount of time, laying the groundwork for more environmentally friendly and self-healing construction material down the line. The researchers grew mycelium from the fungus Neurospora crassa, commonly known as red bread mold, into a dense, scaffold-like structure. Then, they added Sporosarcina pasteurii bacteria. “We like these organisms for several reasons,” Chelsea Heveran, a co-author of the study and an expert in engineered living materials at Montana State University, tells the Debrief’s Ryan Whalen. “First, they do not pose very much threat to human health. S. pasteurii is a common soil microorganism and has been used for years in biomineralization research, including in field-scale commercial applications. N. crassa is a model organism in fungal research.” They also liked that both organisms are capable of biomineralization—the process that forms bones and coral by creating hardened calcium carbonate. To set off biomineralization, the team placed the scaffold in a growing medium with urea and calcium. The bacteria formed calcium carbonate quickly and effectively, making the material stronger. Importantly, the bacteria S. pasteurii was alive, or viable, for at least a month. Live organisms in building material could offer unique properties—such as the ability to self-repair or self-clean—but only as long as they’re alive. This study didn’t test those traits specifically, according to a statement, but the longer lifetime of this material “lays the groundwork for these functionalities.” “We are excited about our results,” Heveran tells New Scientist’s James Woodford. “When viability is sufficiently high, we could start really imparting lasting biological characteristics to the material that we care about, such as self-healing, sensing or environmental remediation.” This month-long lifespan marks a significant improvement over previous structures. In fact, a major challenge in the development of living biomaterials is their short viability—other similar materials made with living organisms have remained viable for just days or weeks. Plus, they don’t usually form the complex internal structures necessary in construction projects, according to the statement. In the new study, however, “we learned that fungal scaffolds are quite useful for controlling the internal architecture of the material,” Heveran explains in the statement. “We created internal geometries that looked like cortical bone, but moving forward, we could potentially construct other geometries, too.” Ultimately, the researchers developed a tough structure that could provide the basis for future sustainable building alternatives. As reported by New Atlas’ Abhimanyu Ghoshal, however, scientists still have other challenges to tackle on the path to replacing concrete—for instance, scaling the material’s production, making it usable for different types of construction projects and overcoming the higher costs associated with living biomaterials. These materials, so far, “do not have high enough strength to replace concrete in all applications,” Heveran says in the statement. “But we and others are working to improve their properties so they can see greater usage.” To that end, Aysu Kuru, a building engineer at the University of Sydney in Australia who did not participate in the study, tells New Scientist that “proposing mycelium as a scaffolding medium for living materials is a simple but powerful strategy.” Get the latest stories in your inbox every weekday.

Researchers are developing the biomaterial as a more environmentally friendly alternative to concrete, but any wide-scale use is still far away