Conversion of lignin to fuels and chemicals using catalysis and biology

Lignin is an energy-dense, heterogeneous polymer comprised of phenylpropanoid monomers used by plants for structure, water transport, and defense. In production of fuels and chemicals from biomass, lignin is typically underutilized as a feedstock and burned for process heat because its inherent heterogeneity and recalcitrance make it difficult to selectively upgrade to value-added products. We have recently demonstrated that aromatic metabolic pathways can be utilized as a “biological funnel” to convert heterogeneous lignin-derived aromatic streams derived from pilot-scale lignin deconstruction processes into intermediates that can be then upgraded into fuels or chemicals. Coupling this novel biological funneling to upstream lignin depolymerization and downstream catalytic upgrading enables a versatile, integrated approach to valorize lignin by overcoming its inherent heterogeneity.