Microbial assimilation of lignin-derived aromatic compounds and conversion to value-added products

•Depolymerized lignin is a complex and variable mix of aromatic compounds.•Non-model microbes can convert these aromatic compounds to useful products.•Known microbial pathways can only assimilate a fraction of the potential lignin-derived substrates.•New products and microbial conversion pathways are needed that advantage lignin as a feedstock.•Tolerance to biomass-derived substrates and inhibitors is often limiting.