Stürtz Melanie, Lander Vera, Schmid Wolfgang, Winterhalter Peter
Institute of Food Chemistry, Technical University of Braunschweig, Germany.
Mol Nutr Food Res. 2006 Apr;50(4-5):356-61. doi: 10.1002/mnfr.200500206.
Numerous studies have demonstrated the potential of isoflavones occurring in soy (Glycine max L.) and red clover (Trifolium pratense L.) to alleviate climacteric complaints. They have also shown beneficial effects on the cardiovascular system and in the prevention of osteoporosis. As a result, several companies offer nutraceuticals based on soy or red clover extracts. The aim of the present study was the isolation of pure isoflavones on a preparative scale, in order to obtain standards for biological tests and for the quantification of isoflavones in nutraceuticals and foods. High-speed countercurrent chromatography, a special type of liquid-liquid partition chromatography, was applied to the preparative isolation of isoflavones. By using this technique the major monoglucosylated and acetylated isoflavones from soy extracts were obtained after a cleaning-up step on Amberlite XAD-7 material. Furthermore, it was possible to isolate isoflavone aglycones as well as glycosides from a red clover extract. Purity and identity of the isolated isoflavones were confirmed by HPLC with DAD, HPLC-ESI multiple-MS, and NMR spectroscopy.
大量研究表明，大豆（Glycine max L.）和红车轴草（Trifolium pratense L.）中含有的异黄酮具有缓解更年期不适的潜力。这些研究还表明，异黄酮对心血管系统有益，并有助于预防骨质疏松症。因此，几家公司推出了以大豆或红车轴草提取物为基础的营养保健品。本研究的目的是在制备规模上分离出纯异黄酮，以便获得用于生物测试以及营养保健品和食品中异黄酮定量分析的标准品。高速逆流色谱法是一种特殊类型的液-液分配色谱法，用于异黄酮的制备分离。通过使用该技术，在对Amberlite XAD-7材料进行净化步骤后，从大豆提取物中获得了主要的单葡萄糖基化和乙酰化异黄酮。此外，还能够从红车轴草提取物中分离出异黄酮苷元以及糖苷。通过配有二极管阵列检测器的高效液相色谱法、高效液相色谱-电喷雾多级质谱法和核磁共振光谱法对分离出的异黄酮的纯度和特性进行了确认。
