State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou, China.
J Agric Food Chem. 2010 Mar 24;58(6):3446-50. doi: 10.1021/jf903998d.
Attempts were made to enhance polysaccharide digestibility by crude cellulases in the isolation of cellulolytic enzyme lignin (CEL) by dissolution of ball-milled wood in a dimethyl sulfoxide (DMSO)/N-methylimidazole solvent system as a pretreatment step. Wood regenerated from the DMSO/N-methylimidazole solution was hydrolyzed with crude cellulases for 48 h, removing 73.7 and 66.9% of the original carbohydrate for basswood and loblolly pine, respectively; only 61.7 and 49.2% were hydrolyzed by the crude cellulases without pretreatment. The yields of CEL isolated from regenerated ball-milled wood samples were therefore higher than those directly from ball-milled wood material, presumably via decreasing crystallinity of cellulose. For basswood, the yields of lignin were 45.8 and 36.5% (based on Klason lignin); for loblolly pine, the yields were 35.3 and 30.5%. The isolated lignins were structurally examined using two-dimensional heteronuclear single-quantum coherence ((1)H-(13)C HSQC) NMR methods, which showed that the main structural characteristics of the lignin fractions obtained using these two methods are similar except for slightly higher amounts of carbohydrates in the solvent dissolution product.
尝试通过粗纤维素酶在二甲亚砜（DMSO）/N-甲基咪唑溶剂体系中溶解球磨木材作为预处理步骤来分离纤维素酶木质素（CEL），以提高多糖的消化率。从 DMSO/N-甲基咪唑溶液中再生的木材用粗纤维素酶水解 48 小时，分别去除白云杉和火炬松原始碳水化合物的 73.7%和 66.9%；未经预处理，粗纤维素酶仅水解 61.7%和 49.2%。因此，从再生球磨木材样品中分离出的 CEL 的产率高于直接从球磨木材材料中分离出的 CEL，这可能是通过降低纤维素的结晶度。对于白云杉，木质素的产率为 45.8%和 36.5%（基于 Klason 木质素）；对于火炬松，木质素的产率为 35.3%和 30.5%。使用二维异核单量子相干（(1)H-(13)C HSQC）NMR 方法对分离出的木质素进行结构分析，结果表明，这两种方法得到的木质素级分的主要结构特征相似，只是在溶剂溶解产物中碳水化合物的含量略高。
