Premium
Preparative isolation of isoflavones from soy and red clover
Author(s) -
Stürtz Melanie,
Lander Vera,
Schmid Wolfgang,
Winterhalter Peter
Publication year - 2006
Publication title -
molecular nutrition and food research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.495
H-Index - 131
eISSN - 1613-4133
pISSN - 1613-4125
DOI - 10.1002/mnfr.200500206
Subject(s) - isoflavones , red clover , chromatography , chemistry , high performance liquid chromatography , nutraceutical , glycoside , soy protein , formononetin , food science , phytoestrogens , daidzein , biochemistry , biology , genistein , botany , organic chemistry , estrogen , endocrinology , genetics
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.