基于LiCl/DMSO全溶体系的巨龙竹组分分离及结构表征

Isolation and structural characterization of bamboo lignin from Dendrocalamus sinicus based on LiCl/DMSO solvent system

使用LiCl/DMSO溶剂体系对巨龙竹粉进行溶解、再生处理后,以二氧六环为溶剂提取木质素,并通过分子量测定、红外光谱和核磁共振波谱对提取组分进行结构表征.结果表明:LiCl/DMSO溶解、再生处理可使竹材木质素溶出率从6.1%提高到9.6%,纯度从82.5%提高到89.4%,碳水化合物含量由15.8%减少到9.2%;从LiCl/DMSO处理竹粉与原始竹粉中提取的均为禾本科木质素,其分子结构单元以β-O-4′(芳基醚键)和β-β′(树脂醇单元)结构为主.该处理方法有助于提高巨龙竹木质素组分的分离效果,同时不会明显破坏竹材木质素的化学结构.

The LiCl/DMSO solvent system is used to isolate lignin fractions from bamboo(Dendrocalamus sinicus)in the present research.The yields,purities and molecule structure of the two bamboo lignin fractions are characterized comparatively.The results indicate that the yields of lignin fractions isolated from the original and the regenerated bamboo are 6.1% and 9.6%,respectively.Meanwhile,the purities of the two lignin fractions are 82.5% and 89.4%,and the carbohydrate contents of the two lignin fractions are 15.8% and 9.2%,respectively.Structural characterization indicates that the bamboo lignin belongs to Gramineae lignin,consisting syringl(S),guaiacyl(G),and p-hydroxylphengl(H)units.The major inter-unit linkages presented in the obtained bamboo lignin areβ-O-4′(aryl ether)andβ-β′(resinol)linkages.In addition,the treatment of LiCl/DMSO solvent does not lead to severe damage and the native structure characteristics of the bamboo lignin are remained during the dissolution and regeneration process.