Structural characterization of lignin from D. sinicus by FTIR and NMR techniques

Abstract

Milled wood lignin (MWL) was isolated from Dendrocalamus sinicus, an abundant bamboo variety in the earth, using Bjorkman method. Elucidation and quantification of the chemical structures for the isolated MWL have been facilitated by employing FT-IR and NMR techniques. The obtained results showed that the MWL consists of syringyl (S), guaiacyl (G), and p-hydroxyphenyl (H) units, indicating it as grass type (HGS) lignin. There is no significant change in structure (i.e. cleavage at α-O-4′ and β-O-4′ linkage) was observed. NMR techniques indicated that the isolated lignin was rich in β-O-4′ aryl ether substructures and syringyl (S) units. Furthermore, the sufficient understanding of the chemical structure of the lignin benefits their effective utilization towards the production of renewable biomass and biofuels.