Karina Hettwer, Steffen Uhlig, Martin Jähne, Sven Krügener, Kirsten Simon (2012)
The detection of estrogens and androgens in drinking and surface water is an important task due to their potential to alter the endocrine system of humans and animals. In cooperation with the IPK (Gatersleben, Germany) we developed and validated innovative yeast based assays for the detection of cumulated estrogenic or androgenic activity in mineral, curative and environmental water. The screening assays are based on the non-conventional salt tolerant yeast Arxula adeninivorans. The human estrogen receptor α (hERα) or alternatively the androgen receptor (hAR) and a phytase as reporter enzyme were integrated in the genome of A. adeninivorans. In the presence of estrogenic or androgenic compounds, receptor-ligand-complexes induce the expression of the secretory reporter enzyme. The estrogen assays are available for different types of samples. A-YES ®_aqua 1.0 and A-YES ®_aqua 2.0 were designed for the detection of estrogenic activity in mineral water. The assays differ in the sensitivity of the method, whereby the A-YES ®_aqua 2.0 is more sensitive. A-YES ®_matrix 1.1 was designed for the detection of estrogenic activity in environmental water samples such as surface-, ground- or brackish water as well as curative water. The limit of detection was determined to be 2.7 ng /L 17-ß-Estradiol (E2) and the quantification interval ranges from 3.7 till 52.1 ng/L E2. The detection of the cumulative androgenic activity in mineral water can be performed using the A-YAS ®_aqua, with a limit of detection of 31.3 ng /L 5-α-Dihydrotestosterone (DHT) and a quantification range from 44.2 till 325.8 ng/L DHT.