Abstract:
The presence of endocrine-disrupting compounds (EDCs) in water poses a significant threat to human and animal health, as recognized by regulatory agencies throughout the world. The Yeast Estrogen Screen (YES) assay is an excellent method to evaluate the presence of these compounds in water due to its simplicity and capacity to assess the bioaccessible forms/fractions of these compounds. In the presence of a compound with estrogenic activity, Saccharomyces cerevisiae cells, containing a lacZ reporter gene encoding the enzyme β-galactosidase, are induced, the enzyme is synthesised, and released to the extracellular medium. In this work, a YES-based approach encompassing the use of a lacZ reporter gene modified strain of S. cerevisiae, microcarriers as solid support, and a fluorescent substrate, fluorescein di-β-d-galactopyranoside, is proposed, allowing for the assessment of EDCs\' presence after only 2 h of incubation. The proposed method provided an EC50 of 0.17 ± 0.03 nM and an LLOQ of 0.03 nM, expressed as 17β-estradiol. The assessment of different EDCs provided EC50 values between 0.16 and 1.2 × 103 nM. After application to wastewaters, similar results were obtained for EDCs screening, much faster, compared to the conventional 45 h spectrophotometric procedure using a commercial kit, showing potential for onsite high-throughput screening of environmental contamination.
摘要:
水中内分泌干扰化合物(EDCs)的存在对人类和动物健康构成了重大威胁。得到世界各地监管机构的认可。酵母雌激素筛选(YES)测定法是评估这些化合物在水中的存在的极好方法,这是由于其简单性和评估这些化合物的生物可接受形式/级分的能力。在具有雌激素活性的化合物存在下,酿酒酵母细胞,含有编码酶β-半乳糖苷酶的lacZ报告基因,是诱导的,酶是合成的,并释放到细胞外培养基中。在这项工作中,一种基于YES的方法,包括使用lacZ报告基因修饰的酿酒酵母菌株,微载体作为固体载体,和荧光基板,荧光素二-β-d-吡喃半乳糖苷,被提议,允许在仅孵育2小时后评估EDC的存在。所提出的方法提供了0.17±0.03nM的EC50和0.03nM的LLOQ,表示为17β-雌二醇。不同EDC的评估提供了在0.16和1.2×103nM之间的EC50值。应用于废水后,EDC筛选获得了类似的结果,快得多,与使用商业试剂盒的常规45小时分光光度程序相比,显示出现场高通量筛查环境污染的潜力。