The total sugar content of SPG-1, SPG-2, SPG-3, and SPG-4 was 97.32, 92.54, 76.65, 99.14% respectively and their contents of protein was 2.15, 6.83 , 22.36, 0.43% respectively.

• 甘薯糖蛋白4个级分SPG-1、SPG-2、SPG-3、SPG-4中总糖含量分别为：97.；32，92