Oosterveld A, Beldman G, Schols H A, Voragen A G
Department of Food Technology and Nutritional Sciences, Wageningen University, The Netherlands.
Carbohydr Res. 2000 Sep 8;328(2):185-97. doi: 10.1016/s0008-6215(00)00095-1.
Pectic polysaccharides were extracted from sugar beet pulp to yield fractions representing homogalacturonans, rhamnogalacturonans, arabinans and relatively small amounts of glucomannans and xyloglucans. The homogalacturonans had an apparent molecular weight of 21 kDa and contained relatively high amounts of methyl esters and relatively low amounts of acetyl groups as compared with the ramified 'hairy' regions. Three populations which originated from the ramified 'hairy' regions of pectin were distinguished. Two of these were rhamnogalacturonans with high apparent molecular weights of 1300 and 120 kDa, respectively. These populations had a high Ara and ferulic acid content. Despite the high neutral sugar content, these rhamnogalacturonans strongly bound to a DEAE column. The third population which originated from the ramified 'hairy' regions was a neutral population, which did not interact with the DEAE column and had a low apparent molecular weight and a high Ara and ferulic acid content. The arabinan side-chains of the rhamnogalacturonans were heavily branched in all populations. Enzymatic degradation of the xyloglucans showed similarities with apple xyloglucans with respect to the substitution with Fuc and Gal.
从甜菜浆中提取果胶多糖，得到代表同型半乳糖醛酸聚糖、鼠李半乳糖醛酸聚糖、阿拉伯聚糖以及相对少量的葡甘露聚糖和木葡聚糖的级分。与分支的“毛状”区域相比，同型半乳糖醛酸聚糖的表观分子量为21 kDa，甲酯含量相对较高，乙酰基含量相对较低。区分了源自果胶分支“毛状”区域的三个群体。其中两个是鼠李半乳糖醛酸聚糖，表观分子量分别高达1300 kDa和120 kDa。这些群体的阿拉伯糖和阿魏酸含量较高。尽管中性糖含量较高，但这些鼠李半乳糖醛酸聚糖与DEAE柱强烈结合。源自分支“毛状”区域的第三个群体是中性群体，它不与DEAE柱相互作用，表观分子量低，阿拉伯糖和阿魏酸含量高。所有群体中鼠李半乳糖醛酸聚糖的阿拉伯聚糖侧链都高度分支。木葡聚糖的酶促降解在岩藻糖和半乳糖取代方面与苹果木葡聚糖表现出相似性。
