13C同位素标记法研究木质素与木聚糖的连接

Study on the Bonds between Lignin and Xylan by 13C-Isotope Tracer Method

摘要: 以带13C标记的松柏醇葡萄糖苷作为木质素的前驱物,在β-葡萄糖苷酶、葡萄糖氧化酶、过氧化物酶的酶体系中,向木聚糖胶体中滴加松柏醇葡萄糖苷的溶液,得到木质素脱氢聚合物(DHP)与木聚糖的复合体,并用FT-IR、13C NMR对DHP-木聚糖复合体(DHPXC)进行分析.结果表明,DHPXC中,木质素结构单元之间主要通过β-O-、β-β、β-5和β-1方式连接,而木质素与木聚糖之间可能通过苯甲酯键和苯甲醚键相连.

Abstract: DHP-xylan complex (DHPXC) were prepared from xylan and coniferin or coniferin-α-13C in the presences of β-glucosidase, glucose oxidase and peroxidase. The result of analysis of DHPXC by CP/MAS 13C NMR and FT-IR spectra showed that β-O- 4、 β-β、 β-5 and β-1 structures were the main substructures of DHP in DHPXC. DHP could be connected with xylan through benzyl ether linkage and ester bond mainly at α-position.