Department of Nutrition and Food Science-XaRTA, Faculty of Pharmacy, University of Barcelona, Av. Joan XXII s/n, Barcelona, Spain.
Food Chem. 2012 Dec 15;135(4):2832-8. doi: 10.1016/j.foodchem.2012.06.011. Epub 2012 Jun 26.
Ultra high pressure liquid chromatography (UHPLC) has become a widely used technique in separation science as it can shorten analysis time while maintaining resolution and increasing sensitivity. Here we developed a UHPLC method with UV detection for the simultaneous determination of isoflavone aglycones (daidzein, glycitein and genistein), their corresponding glycoside forms (daidzin, glycitin and genistin), and acetyl and malonyl conjugate forms of glycosides (malonyldaidzin, malonylglycitin, malonylgenistin, acetyldaidzin, acetylglycitin, acetylgenistin) in soy milk. The method allowed reliable determinations of 12 isoflavones in less than 8 min of chromatographic elution. It provided a satisfactory linearity ranging from 0.1 to 5mg/L, except for daidzin and genistin, for which it ranged from 0.1 to 10mg/L. In addition, it showed acceptable chromatographic sensitivity, with a detection limit lower than 0.05 mg/L and a determination limit below 0.2mg/L. The precision, in terms of relative standard deviation, was lower than 5% and the accuracy, as mean recovery, was greater than 95%. Total isoflavone content in commercial soy milk samples (n=8) ranged from 1805.22 to 3195.59 mg/kg dw. Genistin and Daidzin were the major isoflavones in all samples. The proportion of aglycones, ß-glucosides, and acetyl and malonyl glucosides differed among the samples. ß-Glucosides were identified as the predominant forms.
超高效液相色谱（UHPLC）已成为分离科学中广泛使用的技术，因为它可以在保持分辨率和提高灵敏度的同时缩短分析时间。在这里，我们开发了一种带有紫外检测的 UHPLC 方法，用于同时测定豆奶中异黄酮苷元（染料木黄酮、大豆苷元和染料木苷）、相应的糖苷形式（染料木苷、大豆苷和金雀异黄素）以及糖苷的乙酰基和丙二酰基共轭形式（丙二酰基染料木苷、丙二酰基大豆苷、丙二酰基金雀异黄素、乙酰基染料木苷、乙酰基大豆苷和乙酰基金雀异黄素）。该方法允许在少于 8 分钟的色谱洗脱时间内可靠地测定 12 种异黄酮。它提供了令人满意的线性范围，从 0.1 到 5mg/L，除了染料木苷和金雀异黄素，其范围从 0.1 到 10mg/L。此外，它表现出可接受的色谱灵敏度，检测限低于 0.05mg/L，测定限低于 0.2mg/L。精密度以相对标准偏差表示，低于 5%，准确度以平均回收率表示，大于 95%。8 个商业豆奶样品的总异黄酮含量范围为 1805.22 至 3195.59mg/kg dw。金雀异黄素和染料木苷是所有样品中的主要异黄酮。糖苷元、β-葡萄糖苷和乙酰基和丙二酰基葡萄糖苷的比例在样品之间有所不同。β-葡萄糖苷被确定为主要形式。
