稻子、小麦麸皮中可溶性非淀粉多糖的气相色谱法测定

讨论稻子、小麦麸皮中可溶性非淀粉多糖的气相色谱法测定。将稻子、小麦麸皮磨细后，用８０％乙醇萃取游离糖，剩余物在醋酸缓冲液（ｐＨ５．０）条件下分别用α－淀粉酶和α－葡萄糖苷酶酶解，除掉淀粉。非淀粉多糖用酸水解为各单糖，采用糖醇衍生化成乙酸酯的制备方法，用ＯＶ－１７０１石英毛细管色谱柱，可分离得到非淀粉多糖（ＮＳＰ）各组成单糖的色谱峰。并以自然界中不存在的阿洛糖作内标物，提高了定性定量分析的准确性，计算出了稻子、小麦麸皮中可溶性非淀粉多糖的含量。

Determination of the Soluble Non Starch Polysaccharides in Rice and Wheat Bran by Gas Chromatography

Cereal polysaccharides can be broadly classified into two distinct and chemically well-defined types. They are the storage polysaccharides (alpha-glucan) and the structural polysaccharides starch (beta-glucan) which are usually called non-starch polysaccharides (NSP). The determination of soluble non-starch polysaccharides in rice and wheat bran by gas chromatography has been developed. The free sugars in the sample were extracted with 80% ethanol. The residue was hydrolyzed in an acetic acid buffer solution (pH 5.0) in the presence of amylase and amyloglucosidase to remove starch. The soluble NSP obtained was further hydrolyzed in the acidic condition to produce the corresponding monosaccharides which were derivatized to form alditol acetates for GC analysis with allose as the internal standard. The GC conditions were OV-1701 column (25 m x 0.3 mm) with temperature program from 195 degrees C to 225 degrees C and FID.