title: Quantification of wheat straw lignin structure by comprehensive NMR analysis.
abstract: A further understanding of the structure of lignin from herbaceous crops is needed for advancing technologies of lignocellulosic biomass processing and utilization. A method was established in this study for analyzing structural motifs found in milled straw lignin (MSL) and cellulase-digested lignin (CEL) isolated from wheat straw by combining quantitative (13)C and HSQC NMR spectral analyses. The results showed that guaiacyl (G) was the predominant unit in wheat straw cell wall lignin over syringyl (S) and hydroxyphenyl (H) units. Up to 8.0 units of tricin were also detected in wheat straw lignin per 100 aromatic rings. Various interunit linkages, including β-O-4, β-5, β-β', β-1, α, β-diaryl ether, and 5-5'/4-O-β' as well as potential lignin-carbohydrate complex (LCC) bonds, were identified and quantified. These findings provide useful information for the development of biofuels and lignin-based materials.
authors.affiliation: Department of Biological Systems Engineering, The Bioprocessing and Bioproduct Engineering Laboratory (BBEL), L. J. Smith 213, Washington State University , Pullman, Washington 99163 United States.
authors.forename: Jijiao
authors.initials: J
authors.lastname: Zeng
authors.forename: Gregory L
authors.initials: GL
authors.lastname: Helms
authors.forename: Xin
authors.initials: X
authors.lastname: Gao
authors.forename: Shulin
authors.initials: S
authors.lastname: Chen
mesh_terms: D008031:Lignin / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D018547:Plant Stems / Q000737:chemistry; D014908:Triticum / Q000737:chemistry*
chemical_list: D008031:Lignin