Ohsumi C, Hayashi T
Basic Research Laboratories, Ajinomoto Co. Inc., Kawasaki, Japan.
Plant Cell Physiol. 1994 Sep;35(6):963-7.
Xyloglucans were isolated from the 24% KOH-soluble fraction of the cell walls of bulbs of onion (Allium cepa), garlic (Allium sativum) and their hybrid. The polysaccharides yielded single peaks upon gel filtration with average molecular weights of 65,000 for onion, 55,000 for garlic and 82,000 for the hybrid. Compositional analysis of the oligosaccharide units after digestion with an endo-1,4-beta-glucanase from Streptomyces indicated that the polysaccharides were constructed of four kinds of repeating oligosaccharide unit, namely, a decasaccharide (glucose/xylose/galactose/fucose, 4 : 3: 2 : 1), a nonasaccharide (glucose/xylose/galactose/fucose, 4 : 3 : 1 : 1), an octasaccharide (glucose/xylose/galactose, 4 : 3 : 1), and a heptasaccharide (glucose/xylose, 4 : 3). The xyloglucan from the hybrid contained highly fucosylated units that resembled those from onion rather than from garlic. The analysis also revealed that the xyloglucans from Allium species contain highly substituted xylosyl residues with fucosyl-galactosyl residues, suggesting that these monocotyledonous plants resemble dicotyledons in the structural features of their xyloglucans.
从洋葱（葱属植物）、大蒜（蒜属植物）及其杂交种鳞茎细胞壁的24%氢氧化钾可溶部分中分离出木葡聚糖。这些多糖在凝胶过滤时产生单峰，洋葱的平均分子量为65,000，大蒜的为55,000，杂交种的为82,000。用链霉菌的内切-1,4-β-葡聚糖酶消化后的寡糖单元组成分析表明，这些多糖由四种重复寡糖单元构成，即一个十糖（葡萄糖/木糖/半乳糖/岩藻糖，4 : 3 : 2 : 1）、一个九糖（葡萄糖/木糖/半乳糖/岩藻糖，4 : 3 : 1 : 1）、一个八糖（葡萄糖/木糖/半乳糖，4 : 3 : 1）和一个七糖（葡萄糖/木糖，4 : 3）。杂交种的木葡聚糖含有高度岩藻糖基化的单元，这些单元更类似于洋葱的而非大蒜的。分析还表明，葱属植物的木葡聚糖含有被岩藻糖基-半乳糖基残基高度取代的木糖基残基，这表明这些单子叶植物在其木葡聚糖的结构特征上类似于双子叶植物。
