title: Structural elucidation of the lignins from stems and foliage of Arundo donax Linn.
abstract: As one of the potential energy crops, Arundo donax Linn. is a renewable source for the production of biofuels and bioproducts. In the present study, milled wood lignin (MWL) and alkaline lignin (AL) from stems and foliage of A. donax were isolated and characterized by FT-IR spectroscopy, UV spectroscopy, GPC, ³¹P NMR, 2D HSQC NMR, and DFRC. The results indicated that both stem and foliage lignins were HGS type lignins. The semiquantitative HSQC spectra analysis demonstrated a predominance of β-O-4' aryl ether linkages (71-82%), followed by β-β', β-5', β-1', and α,β-diaryl ethers linkages in the lignins. Compared to stem lignins, foliage lignins had less β-O-4' alkyl-aryl ethers, lower weight-average molecular weight, less phenolic OH, more H units, and lower S/G ratio. Moreover, tricin was found to incorporate into the foliage lignins (higher content of condensed G units) in significant amounts and might be alkaline-stable.
authors: Beijing Key Laboratory of Lignocellulosic Chemistry, Beijing Forestry University , Beijing, China.
authors: Ting-Ting
authors: TT
authors: You
authors: Jian-Zhen
authors: JZ
authors: Mao
authors: Tong-Qi
authors: TQ
authors: Yuan
authors: Jia-Long
authors: JL
authors: Wen
authors: Feng
authors: F
authors: Xu
mesh_terms: D056804:Biofuels / Q000032:analysis*; D002681:China; D018556:Crops, Agricultural / Q000737:chemistry*; D005419:Flavonoids / Q000032:analysis; D017752:Greenhouse Effect / Q000517:prevention & control; D006868:Hydrolysis; D008031:Lignin / Q000737:chemistry* / Q000302:isolation & purification; D015394:Molecular Structure; D008970:Molecular Weight; D018515:Plant Leaves / Q000737:chemistry*; D018547:Plant Stems / Q000737:chemistry*; D006109:Poaceae / Q000737:chemistry*
chemical_list: D056804:Biofuels; D005419:Flavonoids; D008031:Lignin; C017769:tricin