Abstract
Lignocellulose biomass is indispensable for establishing sustainable societies. Trees and large-sized grasses are the major sources of lignocellulose biomass. Moreover, large-sized grasses greatly surpass trees in terms of lignocellulose biomass productivity. With an overall aim to improve lignocellulose usability, it is vital to improve lignin content and simplify lignin structures in biomass plants via lignin metabolic engineering. In this mini review, recent studies of lignin metabolic engineering of grass biomass plants mainly from the authors’ research group are summarized, which includes characterization of lignocellulose properties of large-sized grass biomass plants and the augmentation of lignin content and simplification of lignin structures in grasses.