A rendition of the macromolecular model of the secondary cell wall in poplar wood. Cellulose is shown in white, hemicellulose in green, and lignin in yellow. Figure by Peter Ciesielski, NREL.

A multidisciplinary approach has enabled a research team at the National Renewable Energy Laboratory (NREL) to quantitatively define the relative positioning and arrangement of the polymers in Populus wood, and to create a computer model that details the findings.

The research solving this macromolecular puzzle, Atomistic, Macromolecular Model of the Populus Secondary Cell Wall Informed by Solid-State NMR, which appears in the journal Science Advances, may hold the key to efficiently disentangle and deconstruct biomass for conversion to fuels, chemicals, and materials. Scientists have long known that the secondary cell wall of hardwoods involves three major biopolymers—cellulose, hemicellulose, and lignin—but detailed and quantitative understanding of how these polymers are arranged relative to each other has remained elusive.

The use of solid-state nuclear magnetic resonance allowed researchers to construct a computer model of the cell wall, which provided greater insight into the role lignin plays. Considered a recalcitrant part of the cell wall when it comes to breaking down biomass, lignin is notable for lending plasticity to a plant.

Learn how this research may hold the key to more efficient use of biomass for fuels, chemicals, and materials. This research was funded by the DOE Bioenergy Technologies Office’s (BETO) Feedstock-Conversion Interface Consortium and the Office of Science's Center for Bioenergy Innovation.