Beijing Key Laboratory of Lignocellulosic Chemistry, Beijing Forestry University, Beijing 100083, P. R. China.
State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, P. R. China.
Anal Chem. 2020 Oct 6;92(19):13101-13109. doi: 10.1021/acs.analchem.0c02124. Epub 2020 Sep 17.
Lignocellulosic biomass is mainly composed of polysaccharides and lignin. The complexity and diversity of the plant cell wall polymers makes it difficult to isolate the components in pure form for characterization. Many current approaches to analyzing the structure of lignocellulose, which involve sequential extraction and characterization of the resulting fractions, are time-consuming and labor-intensive. The present study describes a new and facile system for rationally derivatizing and dissolving coarsely ground plant cell wall materials. Using ionic liquids (EmimAc) and dichloroacetyl chloride as a solvent/reagent produced mildly acetylated whole cell walls without significant degradation. The acetylated products were soluble in DMSO- from which they can be characterized by solution-state two-dimensional nuclear magnetic resonance (2D NMR) spectrometry. A distinct advantage of the procedure is that it realizes the dissolution of whole lignocellulosic materials without requiring harsh ball milling, thereby allowing the acquisition of high-resolution 2D NMR spectra to revealing structural details of the main components (lignin and polysaccharides). The method is therefore beneficial to understanding the composition and structure of biomass aimed at its improved utilization.
木质纤维素生物质主要由多糖和木质素组成。植物细胞壁聚合物的复杂性和多样性使得难以将成分以纯形式分离出来进行表征。目前许多分析木质纤维素结构的方法都涉及到对所得级分进行顺序提取和表征，这些方法既耗时又费力。本研究描述了一种新的、简便的方法，用于合理衍生和溶解粗磨植物细胞壁材料。使用离子液体（EmimAc）和二氯乙酰氯作为溶剂/试剂，可在不发生明显降解的情况下温和乙酰化整个细胞壁。乙酰化产物可溶于 DMSO-从中可以通过溶液二维核磁共振（2D NMR）光谱进行表征。该方法的一个显著优点是，它实现了整个木质纤维素材料的溶解，而不需要苛刻的球磨，从而可以获得高分辨率的 2D NMR 谱，揭示主要成分（木质素和多糖）的结构细节。因此，该方法有利于理解旨在提高利用效率的生物质的组成和结构。
