Non-starchy polysaccharides of Colocasia esculenta (L.) Schott (Satoimo) during tuberization and development

Changes in the carbohydrate composition of non-starchy polysaccharides in Satoimo, seed corm, mother corm and cormel, were compared during tuberization and development. The polysaccharides were fractionated by successive extraction with various solvents. In seed corm, the level of non-starchy polysaccharides was relatively low, probably due to tissue degradation. A decrease in the proportion of the cellulosic fraction of the non-starchy polysaccharides was observed in the developing mother corm. In mother corm, the non-starchy polysaccharide content increased gradually through the vegetative stage. However, the proportions of pectic, hemicellulosic and cellulosic fractions in the non-starchy polysaccharides were not changed. The proportions of glucose in hot-water and 0.5% ammonium oxalate-soluble polysaccharides were increased significantly. In cormel, content of the non-starchy polysaccharides tended to decrease during tuber bulking. The proportion of the hemicellulosic fraction decreased and cellulosic fraction increased significantly. The proportions of glucose in hot-water and 0.5% ammonium oxalate-soluble polysaccharides were decreased significantly.