coumestrol and 2-3-bis(3--hydroxybenzyl)butane-1-4-diol

Phytoestrogens (isoflavones, enterolignans and coumestrol) in wastewater samples and surface water samples have been analysed by LC-ESI-MS(n). In wastewater samples, high levels of enterolactone (581-2111 ng/L), daidzein (341-1688 ng/L) and enterodiol (60-834 ng/L) were detected in raw sewage, but the vast majority of the analysed phytoestrogens were removed effectively in the treatment process. The removal rates of the analysed phytoestrogens in the two advanced tertiary treatment plants were >99%; a case study in one of the treatment plants showed that most of the residual phytoestrogens were removed by biological treatment using activated sludge. In surface water samples, daidzein was found at concentrations ranging from 2 ng/L to 33 ng/L in samples from two creeks, and up to 120 ng/L in surface water (pond) on a dairy farm. The analytical results suggest that direct excretions of livestock discharged from farmyards can be another potential source of phytoestrogen contamination in the aquatic environment.

Topics: 4-Butyrolactone; Chromatography, Liquid; Coumestrol; Dairying; Environmental Monitoring; Fresh Water; Isoflavones; Lignans; Phytoestrogens; Spectrometry, Mass, Electrospray Ionization; Waste Disposal, Fluid; Water Pollutants, Chemical

In an international context of promoting scientific research on food safety, the interest in molecules having potential hormonal disrupting effects is growing. While industrial endocrine disruptors (phthalates, alkylphenols, PCBs, etc.) have been studied for several years, natural compounds like phytoestrogens remain less investigated. Accordingly, a research project was initiated with its main objectives to develop efficient analytical methods for a wide range of phytoestrogens in various food matrices, and to evaluate their occurrence in food products. Electrospray ionization with tandem mass spectrometric (MS/MS) analysis of isoflavones (genistein, daidzein, equol, formononetin, biochanin A), lignans (enterolactone, enterodiol), and coumestans (coumestrol) was investigated. This study revealed the formation of a large number of fragment ions in both positive and negative modes, corresponding to specific cleavages of the hydroxyl, carbonyl, and/or methoxy groups, and to Retro-Diels-Alder reactions. An LC/ESI-MS/MS method was developed consistent with the 2002/657/EC European decision criteria. An extraction and clean-up method was developed for milk samples. The identification limit for the proposed method appears to be under 1 ng/mL. The developed methodology was applied to various milk samples, and the occurrence of isoflavones (particularly equol) was demonstrated in the concentration range 1-30 ng/mL. The efficiency of the proposed analytical method permitted evaluation of a new and promising approach to a global risk assessment of natural estrogenic active substances including phytoestrogens and their metabolites.

Topics: 4-Butyrolactone; Animals; Cattle; Chromans; Chromatography, Liquid; Coumestrol; Equol; Estrogens, Non-Steroidal; Genistein; Ions; Isoflavones; Lignans; Milk; Molecular Structure; Phytoestrogens; Plant Preparations; Spectrometry, Mass, Electrospray Ionization