多糖存在下异丁香酚的脱氢聚合及LCC的形成

以异丁香酚为木质素生物合成的前驱物,采用混合法合成了木质素脱氢聚合物(DHP)和木质素-碳水化合物复合体(LCC),同时采用红外光谱、13C NMR波谱分析聚合产物的结构,探讨了漆酶催化脱氢聚合过程中形成的DHP与多糖(阿拉伯半乳聚糖)的聚合反应机理。结果表明:在漆酶的催化作用下,异丁香酚与阿拉伯半乳聚糖发生聚合形成了DHP与LCC,13C NMR波谱结果证实DHP中以β-O-4,β-β,β-5和β-1等结构为主,而LCC的13C NMR谱图中既有来自木质素的芳香族碳原子的信息,也有来自阿拉伯半乳聚糖的共振信号。

Dehydrogenation Polymerization of Isoeugenol and Formation of Lignin-carbohydrate Complexes with Presence of Polysaccharide

Dehydrogenation polymer ( DHP ) and lignin-carbohydrate complexes ( LCC ) were prepared using isoeugenol as precursor of lignin biosynthesis by mixing method. The chemical structure of the polymers was analyzed with Fourier transform infrared spectroscopy ( FT-IR ) and 13C NMR spectroscopy. The dehydrogenation polymerization reaction between DHP and polysaccharide ( arabinogalactan) using the laccase as catalyst was investigated. The results showed that isoeugenol could be polymerized with arabinogalactan to form DHP and LCC catalyzed by laccase. The analysis of the 13C NMR spectra also indicated that the DHP was mainly composed ofβ-O-4,β-β,β-5 andβ-1 subunits. The information from the aromatic carbons of lignin and resonance signals of the arabinogalactan could be found in the 13C NMR spectrum of the LCC.