Zandleven Joris, Sørensen Susanne Oxenbøll, Harholt Jesper, Beldman Gerrit, Schols Henk A, Scheller Henrik V, Voragen Alphons J
Laboratory of Food Chemistry, Department of Agrotechnology and Food Sciences, Wageningen University, P.O. Box 8129, 6700 EV Wageningen, The Netherlands.
Phytochemistry. 2007 Apr;68(8):1219-26. doi: 10.1016/j.phytochem.2007.01.016. Epub 2007 Mar 2.
Evidence is presented for the presence of xylogalacturonan (XGA) in Arabidopsis thaliana. This evidence was obtained by extraction of pectin from the seeds, root, stem, young leaves and mature leaves of A. thaliana, followed by treatment of these pectin extracts with xylogalacturonan hydrolase (XGH). Upon enzymatic treatment, XGA oligosaccharides were primarily produced from pectin extracts obtained from the young and mature leaves and to a lesser extent from those originating from the stem of A. thaliana. The oligosaccharide GalA(3)Xyl was predominantly formed from these pectin extracts. No XGA oligosaccharides were detected in digests of pectin extracts from the seeds and roots. A low number of XGA oligosaccharides was obtained from pectins of A. thaliana. This indicates a uniform distribution of xylose in XGA from A. thaliana. The predominant production of GalA(3)Xyl, as well as the release of linear GalA oligosaccharides pointed to a lower degree of xylose substitution in XGA from A. thaliana than in XGA from apple and potato. The estimated amount of XGA accounted for approximately 2.5%, 7% and 6% (w/w) of the total carbohydrate in the pectin fraction of the stem, young leaves and mature leaves, respectively.
有证据表明拟南芥中存在木糖半乳糖醛酸聚糖（XGA）。该证据是通过从拟南芥的种子、根、茎、幼叶和成熟叶中提取果胶，然后用木糖半乳糖醛酸聚糖水解酶（XGH）处理这些果胶提取物而获得的。经过酶处理后，XGA寡糖主要从幼叶和成熟叶的果胶提取物中产生，从拟南芥茎的果胶提取物中产生的较少。寡糖GalA(3)Xyl主要由这些果胶提取物形成。在种子和根的果胶提取物消化物中未检测到XGA寡糖。从拟南芥的果胶中获得的XGA寡糖数量较少。这表明木糖在拟南芥XGA中的分布是均匀的。GalA(3)Xyl的主要产生以及线性GalA寡糖释放表明，与苹果和马铃薯的XGA相比，拟南芥XGA中木糖取代程度较低。估计XGA的量分别占茎、幼叶和成熟叶果胶部分总碳水化合物的约2.5%、7%和6%（w/w）。
