Mycelium-Based Leather-Like Materials for Sustainable Geotechnical Applications

The need for sustainable construction and geotechnical materials continues to grow as environmental concerns drive innovation in civil engineering applications. Despite advancements in bio-based alternatives, the use of carbon-intensive materials remains widespread in geotechnical engineering. To address this gap, this systematic review of mycelium-based leather-like materials (MBLLM) evaluates their potential as sustainable alternatives for geotechnical applications through three key objectives: (1) systematically analyzing the mechanical properties of MBLLM relevant to geotechnical applications, (2) identifying correlations between the different mechanical properties of MBLLM with species selection, substrate engineering, processing parameters, and strengthening mechanisms, and (3) comparing MBLLM properties with conventional geotextile requirements. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, a comprehensive search across Scopus, Web of Science, and Google Scholar databases identified 236 studies, of which 15 peer-reviewed studies published between 2017 and 2024 met the rigorous inclusion criteria. The analysis revealed significant variations in tensile strength (0.5-40.4 MPa), Young's modulus (3.2-2727 MPa), and elongation at break (1 - 69.74%). Genetically modified Schizophyllum commune and Ganoderma lucidum emerged as the most promising fungal species, while post-processing treatments, including glycerol addition, zinc cross-linking, and heat pressing, significantly enhanced their mechanical performance. The systematic comparison with conventional geotextile materials identified critical performance gaps, particularly in their mechanical behavior (e.g., puncture resistance). Four key research priorities were identified for developing MBLLM, which can be adopted for different geotechnical engineering applications. This study provides researchers and practitioners with evidence-based strategies for developing MBLLM in the form of mycelium-based biogeotextile materials (MBBM) for sustainable soil stabilization, erosion control, and ground improvement applications.