Carlsberg Laboratory, Gamle Carlsberg Vej 10, DK-1799 Copenhagen V, Denmark.
Carlsberg Research Laboratory, Gamle Carlsberg Vej 10, DK-1799 Copenhagen V, Denmark.
Carbohydr Polym. 2014 Nov 4;112:587-94. doi: 10.1016/j.carbpol.2014.06.049. Epub 2014 Jun 25.
The biodegradation of abundantly available cell wall polysaccharides has recently received much attention, not least because cell wall polysaccharides are substrates for the human gut microbiota and for environmentally sustainable processes of biomass conversion to value-added compounds. A major fraction of cereal cell wall polysaccharides consists of arabinoxylans. Arabinoxylan and its degradation products are therefore present in a variety of agro-industrial residues and products. Here, we undertook to track the structural details of wheat arabinoxylan degradation with high resolution NMR spectroscopy. More than 15 carbohydrate residues were distinguished in the substrate and more than 20 residues in partially degraded samples without any sample cleanup. The resolution of a plethora of structural motifs in situ permits the readout of persisting structures in degradation processes and in products. Reaction progress was visualized for the biodegradation of arabinoxylan by different crude microbial enzyme preparations. The direct observation of structural details in complex mixtures containing arabinoxylan fragments is significant, as such structural details reportedly modulate the health-promoting functions of arabinoxylan fragments.
最近，大量存在的细胞壁多糖的生物降解受到了广泛关注，这主要是因为细胞壁多糖是人类肠道微生物群的底物，也是环境可持续的生物质转化为增值化合物的过程的底物。谷物细胞壁多糖的主要成分是阿拉伯木聚糖。因此，阿拉伯木聚糖及其降解产物存在于各种农业工业残渣和产品中。在这里，我们采用高分辨率 NMR 光谱技术，对小麦阿拉伯木聚糖的降解结构细节进行了研究。在底物中区分出了 15 个以上的碳水化合物残基，在部分降解的样品中区分出了 20 个以上的残基，而无需进行任何样品净化。在原位区分大量结构基序的分辨率允许在降解过程和产物中读取残留结构。我们还通过不同的粗微生物酶制剂观察了阿拉伯木聚糖的生物降解过程中的反应进展。在含有阿拉伯木聚糖片段的复杂混合物中直接观察结构细节非常重要，因为据报道，这种结构细节可以调节阿拉伯木聚糖片段的促进健康的功能。
