Structural characterization of lignin from wheat straw

Abstract

Enzyme/mild acidolysis lignin (EMAL) was isolated from wheat straw. The structural characterization of wheat straw EMAL was investigated by FT-IR, 1H NMR, quantitative 31P NMR and DFRC, and DEPT CH (θ = 135C°) techniques. The wheat straw EMAL was a GSH-lignin with β-O-4' structures and several condensed units (β-5', β-β', β-1', 5-5') and vinyl ether moieties; the contents of DBDO substructures and total β-aryl ether in the wheat straw EMAL were 0.257 mmol·g-1 and 0.818 mmol·g-1, respectively. Meanwhile, the structure features of the hemicelluloses residues attached to lignin were also investigated using DEPT CH (θ = 135C°) spectra. © Springer-Verlag 2010.