• search hit 1 of 1
Back to Result List

Is Equol an Ecologically Relevant Endocrine Disruptor? Equol Determination in Cattle Manure by Effect-Directed Analysis Using the pYES Test

  • We present a planar chromatographic separation method for the phytoestrogenic active compound equol, separated on RP-18 W (Merck, 1.14296) phase. It could be shown that an ethanolic cattle manure extract contains this phytoestrogenic active compound to a larger amount. As solvents for the mobile phase, hexane, ethyl acetate, and acetone (45:15:10, v/v); acetone and water (15:10, v/v); andWe present a planar chromatographic separation method for the phytoestrogenic active compound equol, separated on RP-18 W (Merck, 1.14296) phase. It could be shown that an ethanolic cattle manure extract contains this phytoestrogenic active compound to a larger amount. As solvents for the mobile phase, hexane, ethyl acetate, and acetone (45:15:10, v/v); acetone and water (15:10, v/v); and n-hexane, CH2Cl2, ethyl acetate, methanol, and formic acid (40:40:20:5:1, v/v) have been used. After separation, a modified yeast estrogen screen (YES) test was applied, using the yeast strain Saccharomyces cerevisiae BJ3505 containing an estrogen receptor. Its activation by equol induces the reporter gene lacZ which encodes the enzyme β-galactosidase. The enzyme activity is measured directly on the TLC plate by using the substrate MUG (4-methylumbelliferyl-β-d-galactopyranoside) or the substrate X-β-Gal (5-bromo-4-chloro-3-indoxyl-β-d-galactopyranoside). β-Galactosidase cleaves MUG into a fluorescing compound. X-β- Gal is also hydrolyzed and then oxidized by oxygen forming the deep-blue dye 5,5′-dibromo-4,4′-dichloro-indigo. Both reactions in combination with a thin-layer chromatography (TLC) separation allow very specific detecting of equol in cattle manure, although that is a very challenging matrix. Preliminary results show that the average content of equol in liquid manure is roughly 60 μg g−1. The value for urine is 50 μg mL−1.show moreshow less

Export metadata

Additional Services

Share in Twitter Search Google Scholar
Metadaten
Author:Yvonne Anna Minar, Barbara Milz, Bernd SpangenbergGND
Publisher:Akadémiai Kiadó
Place of publication:Budapest
Year of Publication:2018
Language:English
Tag:Effect-directed analysis; Equol in cattle manure; High-performance thin-layer chromatography; Phytoestrogen equol; Thin-layer chromatography; Yeast estrogen screen assay
Parent Title (English):Journal of Planar Chromatography
Volume:31
Issue:1
ISSN:0933-4173
First Page:72
Last Page:78
Document Type:Article (reviewed)
Institutes:Hochschule Offenburg / Bibliografie
Acces Right:Zugriffsbeschränkt
Release Date:2019/01/08
Licence (German):License LogoEs gilt das UrhG
DOI:https://doi.org/10.1556/1006.2018.31.1.9