十一份甘薯种质资源的可溶性糖含量测定与差异分析

HPLC-ELSD法测定植物可溶性糖具有灵敏度高、检出限低、线性范围大等优点。为了了解甘薯品种的可溶性糖组分和糖化特点,对11份甘薯重要种质资源的生薯和熟薯可溶性糖含量进行了测定和差异分析。结果表明,甘薯的生薯和熟薯均含有果糖、葡萄糖、蔗糖和麦芽糖,试验群体的平均含量分别为58.41 mg·g^-1和123.05 mg·g^-1。在生薯可溶性糖中,蔗糖含量最高,占可溶性糖的45%左右,麦芽糖含量最低,仅占可溶性糖的10%左右。在熟薯可溶性糖中,麦芽糖含量最高,其中约90%来源于蒸熟过程中淀粉的转化,增量可占熟薯可溶性糖的50%以上。熟薯中的果糖、葡萄糖、蔗糖主要来源于生薯可溶性糖,在甘薯蒸熟过程中变化较小。因此,甘薯的熟薯可溶性糖含量高低是由麦芽糖含量决定的。浙薯13蒸熟糖化效果好,熟薯可溶性糖和麦芽糖含量分别为179.64 mg·g^-1和138.44 mg·g^-1,均显著高于其余10个品种。红皮白心是一个生薯高糖品种,生薯可溶性糖和果糖含量均居参试品种之首。

Determination and difference analysis of soluble sugar content in 11 sweetpotato germplasm resources

The determination method of plant soluble sugar by HPLC-ELSD has the advantages of high sensitivity, low detection limit and large linear range. In order to understand the soluble sugar components and saccharification characteristics of sweetpotato varieties, the soluble sugar content of 11 important sweetpotato germplasm resources had been measured and analyzed. The results showed that fructose, glucose, sucrose and maltose were all contained in the soluble sugars of both raw root and cooked root,and the average content of the tested group were 58.41 mg·g^-1 and 123.05 mg·g^-1, respectively. Among the soluble sugars in raw root, sucrose content was the highest, accounting for about 45% of the soluble sugars, while maltose was the least, only accounting for about 10% of the soluble sugars. Among the soluble sugars in cooked root, maltose was the highest, about 90% of which came from the conversion of starch during steaming, and the increment accounted for more than 50% of the soluble sugars in cooked root. Fructose, glucose and sucrose in cooked root mainly came from soluble sugars in raw root, while their changes were small during steaming. Therefore, soluble sugar content in cooked root of sweetpotato was determined by maltose content. Zheshu 13 had a good effect of saccharification after steaming, in which the content of soluble sugar and maltose were 179.64 mg·g^-1 and 138.44 mg·g^-1, respectively, significantly higher than the other 10 varieties. Hongpibaixin was a variety with high sugar in raw root, and the content of soluble sugar and fructose in raw root ranked first among the varieties tested.