ANALYSIS OF ISOFLAVONES IN NATURAL SOURCES AND NUTRITIONAL SUPPLEMENTS BY LIQUID CHROMATOGRAPHY AND MULTI-CHANNEL ELECTROCHEMICAL DETECTION

A simple gradient reverse-phase liquid chromatographic method has been developed for the separation of daidzin, genistin, daidzein, and genistein in various natural sources and dietary supplements. Peak assignment at various retention times was confirmed by comparison of the simultaneous response of sample peaks to standards, at glassy carbon electrodes held at different oxidation potentials, using a multi-channel electrochemical detector. Identification was substantiated by ESI MS/MS fragmentation patterns. The analytes of interest were extracted by sonicating raw materials in cold 80% methanol/water for 10 minutes. The concentration of the named isoflavones in various dry food and nutritional supplements was determined using the present LCEC procedure.

[1]  P. Kissinger,et al.  LIQUID CHROMATOGRAPHY WITH MULTI-CHANNEL ELECTROCHEMICAL DETECTION FOR THE DETERMINATION OF RESVERATROL IN WINE, GRAPE JUICE, AND GRAPE SEED CAPSULES WITH AUTOMATED SOLID PHASE EXTRACTION , 2000 .

[2]  M. Messina Legumes and soybeans: overview of their nutritional profiles and health effects. , 1999, The American journal of clinical nutrition.

[3]  M. Ronis,et al.  An LC-MS method to determine concentrations of isoflavones and their sulfate and glucuronide conjugates in urine. , 1999, Clinica chimica acta; international journal of clinical chemistry.

[4]  G. Beecher,et al.  Isoflavones in retail and institutional soy foods. , 1999, Journal of agricultural and food chemistry.

[5]  K. Setchell,et al.  Dietary isoflavones: biological effects and relevance to human health. , 1999, The Journal of nutrition.

[6]  P. Murphy,et al.  Soy isoflavone analysis: quality control and a new internal standard. , 1998, The American journal of clinical nutrition.

[7]  K. Setchell,et al.  Phytoestrogens: the biochemistry, physiology, and implications for human health of soy isoflavones. , 1998, The American journal of clinical nutrition.

[8]  S. Barnes Evolution of the Health Benefits of Soy Isoflavones , 1998, Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine.

[9]  S. Barnes,et al.  HPLC-Mass Spectrometry Analysis of Isoflavones , 1998, Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine.

[10]  A. Franke,et al.  HPLC Analysis of Isoflavonoids and Other Phenolic Agents from Foods and from Human Fluids , 1998, Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine.

[11]  K. Barnes,et al.  A microbore high performance liquid chromatography/electrospray ionization mass spectrometry method for the determination of the phytoestrogens genistein and daidzein in comminuted baby foods and soya flour. , 1998, Rapid communications in mass spectrometry : RCM.

[12]  S. Barnes,et al.  Analysis of plasma isoflavones by reversed-phase HPLC-multiple reaction ion monitoring-mass spectrometry. , 1996, Clinica chimica acta; international journal of clinical chemistry.

[13]  A. Franke,et al.  High-performance liquid chromatographic assay of isoflavonoids and coumestrol from human urine. , 1994, Journal of chromatography. B, Biomedical applications.

[14]  A. Franke,et al.  Quantitation of Phytoestrogens in Legumes by HPLC , 1994 .

[15]  P. Murphy,et al.  Isoflavone composition of American and Japanese soybeans in Iowa: effects of variety, crop year, and location , 1994 .

[16]  I. Acworth,et al.  Analysis of phenolic and flavonoid compounds in juice beverages using high-performance liquid chromatography with coulometric array detection. , 1993, Journal of chromatography.

[17]  S. Lunte,et al.  Structural classification of flavonoids in beverages by liquid chromatography with ultraviolet-visible and electrochemical detection. , 1987, Journal of chromatography.

[18]  P. Kissinger,et al.  Identification of phenolic constituents in commercial beverages by liquid chromatography with electrochemical detection. , 1981, Analytical chemistry.

[19]  S. Lunte,et al.  Detection and identification of procyanidins and flavanols in wine by dual-electrode liquid chromatography-electrochemistry. , 1988, The Analyst.

[20]  C. Lim,et al.  High-performance liquid chromatographic analysis of phytoestrogens in soy protein preparations with ultraviolet, electrochemical and thermospray mass spectrometric detection. , 1987, Journal of chromatography.