P-19　種々リグノセルロースから単離した天然リグニンの溶液中での発光特性

抄録

Lignin, a major cell wall component of woody biomass, is the most abundant aromatic polymer on Earth. Lignin exhibits a photoluminescence (PL) property as long as the distance between luminophores maintained, and is expected to be converted into value-added materials. Since the chemical lignin structures varies among different taxonomical species, their PL properties would be different one another. In this study, natural lignins (cellulolytic enzyme lignin; CEL) were isolated from a variety of species including softwoods, hardwoods, and monocotyledons, and their PL properties were analyzed in various solvents, such as N,N-dimethylformamide and chloroform. As a result, all CELs exhibited clear PL in solution, and their PL properties were different in each species. CELs derived from softwoods showed higher PL intensity compared to that from other species. Notably, among hardwoods, beech, poplar and mulberry demonstrated variations in their UV-Vis spectra, which would be due to the side-chain structure such as p-coumarate and p-hydroxybenzoate. In monocotyledons, maize and bamboo showed clear UV-Vis absorbance and PL at longer wavelengths due to the side-chain structure. These findings indicate significant potential for controlling the PL properties of lignin.