Multiscale Engineering of Lignocellulosic Materials: from Hierarchical Deconstruction to Genetic Reprogramming

The widespread reliance on fossil-derived materials has enabled modern manufacturing but has also driven plastic pollution, carbon emissions, and end-of-life waste challenges. Lignocellulosic biomass offers a renewable and biodegradable alternative, yet its intrinsic heterogeneity has historically limited precise materials design. In this Review, we present a unified multiscale engineering framework for lignocellulosic materials, using wood as an archetypal system to illustrate how structure–property–function relationships can be deliberately programmed from the molecular to the macroscopic scale. We synthesize recent advances in hierarchical deconstruction (top-down processing of cell-wall polymers into micro-, nano-, and molecular building blocks) alongside emerging hierarchical assembly strategies enabled by genetic reprogramming of cellulose, hemicellulose, and lignin biosynthesis. This convergence enables unprecedented control over composition, anisotropy, interfaces, and transport pathways, yielding biomass-derived materials with tailored mechanical, optical, barrier, and electrochemical performance. We further discuss how these approaches reduce feedstock heterogeneity, improve process efficiency, and align materials development with circular-economy principles, carbon sequestration, and low-impact manufacturing. By linking molecular-level design and genetic modification to scalable processing routes and device-level functionality, this review positions engineered lignocellulosic materials as credible, high-performance alternatives to fossil-based plastics and composites, with transformative implications for energy, environmental, and sustainable manufacturing applications.