Sustainable Mycelium Biocomposites: A Systematic Review and Meta-Analysis of Strain, Substrate, and Processing Effects on Material Properties

Mycelium-based biocomposites utilize fungal hyphal polymers to bind lignocellulosic substrates, offering a sustainable alternative to conventional materials. However, the quantitative impacts of fungal strain, substrate chemistry, and post-processing on material performance require systematic clarification. We present a PRISMA 2020-compliant meta-analysis of 35 eligible full-text records (from 1,053 initial reports) to evaluate seven mechanical and physical properties using forest and funnel plots.Pooled estimates demonstrate a mean compressive strength of 0.44 MPa, an acoustic absorption coefficient of 0.64 at 1,600 Hz, and a thermal conductivity of 0.042 W/mK, rivaling traditional mineral wool. Post-processing proved critical: heat-pressing enhanced flexural strength by 184%, and wet-processing spent mushroom substrates decreased water absorption by 73%. Notably, Ganoderma sessile grown on green waste or wheat straw achieved the lowest thermal conductivity. These findings establish the strain–substrate–processing axis as the primary driver of biocomposite performance, providing a data-driven framework for rational material design in the packaging and building sectors.