Department of Food Science, University of Copenhagen, Frederiksberg C, Denmark.
Biomacromolecules. 2011 May 9;12(5):1844-50. doi: 10.1021/bm2001928. Epub 2011 Apr 14.
Hydration of rhamnogalacturonan-I (RG-I) derived from potato cell wall was analyzed by (13)C single-pulse (SP) magic-angle-spinning (MAS) and (13)C cross-polarization (CP) MAS nuclear magnetic resonance (NMR) and supported by (2)H SP/MAS NMR experiments. The study shows that the arabinan side chains hydrate more readily than the galactan side chains and suggests that the overall hydration properties can be controlled by modifying the ratio of these side chains. Enzymatic modification of native (NA) RG-I provided samples with reduced content of arabinan (sample DA), galactan (sample DG), or both side chains (sample DB). Results of these samples suggested that hydration properties were determined by the length and character of the side chains. NA and DA exhibited similar hydration characteristics, whereas DG and DB were difficult to hydrate because of the less hydrophilic properties of the rhamnose-galacturonic acid (Rha-GalA) backbone in RG-I. Potential food ingredient uses of RG-I by tailoring of its structure are discussed.
通过（13）C 单脉冲（SP）魔角旋转（MAS）和（13）C 交叉极化（CP）MAS 核磁共振（NMR）分析了来自马铃薯细胞壁的鼠李半乳糖醛酸聚糖 I（RG-I）的水合作用，并通过（2）H SP/MAS NMR 实验得到了支持。该研究表明，阿拉伯聚糖侧链比半乳聚糖侧链更容易水合，并表明通过改变这些侧链的比例可以控制整体水合性质。对天然（NA）RG-I 的酶修饰提供了阿拉伯聚糖含量降低的样品（样品 DA）、半乳聚糖含量降低的样品（样品 DG）或两种侧链含量都降低的样品（样品 DB）。这些样品的结果表明，水合性质取决于侧链的长度和性质。NA 和 DA 表现出相似的水合特征，而 DG 和 DB 由于 RG-I 中鼠李糖-半乳糖醛酸（Rha-GalA）主链的亲水性较差而难以水合。通过调整 RG-I 的结构，探讨了其作为潜在食品成分的用途。
