一种同时测定小麦种子中直链淀粉、总淀粉含量的新方法——微量分光光度法

A Novel Micro-amount Method with Spectrophotometer to Determine Amylose and Total Starch Content of Wheat Seeds

直链淀粉和总淀粉含量是决定小麦品质的重要指标之一,同时又和小麦的保健功能密切相关,小麦优良品种选育和加工研究都需要快速、简便、微量的测定方法。文中以国标GB7648—1987为基础研究出了一种测定小麦种子中直链淀粉、总淀粉含量的新方法——微量分光光度法(MAS)。直链淀粉含量的测定结果表明,在取样10mg、不脱脂、65℃水浴碱溶12h的情况下,10份小麦样品的组内平行实验误差及与国标法测定结果相比的误差皆<2%,在国标允许的误差范围之内。用可溶性淀粉做标准样品绘制标准曲线,即可同时求得总淀粉含量,组内平行试验误差和与国标法相比的组间误差皆<1%,在国标的允许范围之内。研究结果证明,微量分光光度法具有样品用量少(仅为国标法1/10)、无需样品脱脂、碱溶温度低、环境污染小、省时省力、快捷准确、重复性好、便于样品的批量测定等特点。

The amylose and total starch content are important parameters which determined wheat quality as well as the health function of wheat. Quick, simple and minimal-quantity determinations of amylose and total starch contents is required in selecting and breeding of excellent quality wheat and processing research. A novel mi-croamount method with spectrophotometer（MAS） was discovered on the basis of national standard GB7648--1987 with some improvements. Determination results of amylose content showed that parallel errors of 10 wheat samples using the MAS were less than 2% of 10rag samples by using non- degreasing and basal dissolution at 65℃ for 12 h; the errors between MAS and GB7648-1987 method were also less than 2% ; both kinds of errors were accepted according to GB7648-1987. The total starch content was also determined at the same time using the standard curve of water-solvable starch by MAS, the errors of two parallel experiments in group and between groups of MAS and GB are less than 1%, which were also permitted according to GB. The results indicated that MAS is characterized with needing micro-amount sample（1/10 of GB）, no need of degreasing, lower temperature, lower pollution, saving time and labor, quick and acuteness, quality-repetition, and easy batch-determination.