Soy isoflavone analysis: quality control and a new internal standard
Soy isoflavone analysis: quality control and a new internal standard
复制标题
DOI：
10.1093/ajcn/68.6.1474s
复制
发表时间：
1998-12-01
影响因子：
7.1
通讯作者：
Murphy, PA
中科院分区：
文献类型：
--
作者：
Song, TT;Barua, K;Murphy, PA
食品中大豆异黄酮含量数据库的开发需要对不同食品基质进行准确和精确的评估。为了评估准确性，我们每周估计 5 种不同大豆食品的内部和外部标准的回收率。每天都会评估标准以保证系统质量。为了评估样本精度，我们每两个月分析一次大豆和豆奶的日内精度，并分析超过 4 天的日间精度。 CV 应小于或等于 8%。我们使用新的内标 2,4,4'-三羟基脱氧安息香以及外标大豆黄酮、染料木黄酮和染料木苷验证了我们的单次和多次回收浓度方法。在多种大豆和大豆食品中测量了 12 种异黄酮异构体、3 种苷元（黄豆苷元、染料木黄酮和黄豆黄素）和 9 种糖苷（黄豆苷、染料木苷、黄豆黄素、乙酰黄豆苷、乙酰黄豆苷、乙酰黄豆黄素、丙二酰黄豆苷、丙二酰染料木黄酮和丙二酰黄豆黄素）的浓度。使用的提取方法取决于大豆食品的类型。改进了大豆异黄酮分析的 HPLC 条件，在较短的分析时间（60 分钟/样品）下实现了良好的分离。建立了不同豆制品中异黄酮浓度和分布的数据库，在不同豆制品中发现了从20 000μg/g起的各种异黄酮浓度。糖苷形式几乎是苷元分子量的两倍；报告的异黄酮浓度应标准化为苷元质量（或异黄酮当量），而不是所有异构体的简单总和。
Development of a database of the soy isoflavone content of foods requires accurate and precise evaluation of different food matrixes. To evaluate accuracy, we estimated recoveries of both internal and external standards in 5 different soyfoods weekly. Standards were evaluated daily for system quality assurance. To evaluate sample precision, we analyzed soybeans and soymilk bimonthly for within-day precision and over 4 d for day-to-day precision. CVs should be less than or equal to 8%. We validated our methods for single and multiple recovery concentrations by using our new internal standard, 2,4,4'-trihydroxydeoxybenzoin, and the external standards daidzein, genistein, and genistin. Concentrations of 12 isoflavone isomers, 3 aglycones (daidzein, genistein, and glycitein), and 9 glucosides (daidzin, genistin, glycitin, acetyldaidzin, acetylgenistin, acetylglycitin, malonyldaidzin, malonylgenistin, and malonylglycitin) were measured in a variety of soybeans and soyfoods. The extraction methods used depended on soyfood type. The HPLC conditions for soy isoflavone analysis were improved, leading to good separation with a short analysis time (60 min/sample). A data bank of concentration and distribution of isoflavones in different soybean products was assembled, a wide range of isoflavone concentrations, from 20 000 mu g/g, was found in different soy products. The glucoside forms are almost twice the molecular weight of the aglycones; reported isoflavone concentrations should be normalized to the aglycone mass (or an isoflavonoid equivalent) rather than a simple sum of all isomers.