Abstract

The occurrence of emerging contaminants, such as estrogens, in secondary and tertiary treated effluents and in sewage-impacted water bodies is one of the major obstacles to the implementation of water reuse. This review critically evaluates the performance of emerging process of enzymatic degradation of estrogens, and its efficiency. The data collected from peer-review literature show that enzymes have been extensively applied (in both free and immobilized form) in estrogen removal. Amongst others, the use of laccase as a catalyst provides over 90% removal of estrogens. Immobilized enzymes can overcome some limitations of the free biocatalysts, including reusability. Research evidence points to the formation of by-products, such as dimers and trimers. Nevertheless, estrogenic activity assessment indicates a reduction in toxicity after enzyme treatment. The cost and stability of enzymes, as well as their performance in a real wastewater matrix, are the major obstacles to the implementation of enzymatic processes in wastewater treatment. Continued endeavors are required to enhance the successful application of enzymes in the wastewater treatment industry.

• Highlights

• Processes of enzyme-supported conversion of estrogens are reviewed and discussed.

• Laccase is the most commonly applied enzyme and achieves over 90% estrogen removal.

• Immobilization is suggested as an effective tool for enhancement of estrogen removal.

• Dimers and trimers have been identified as main bioconversion products of estrogens.

• Existing research gaps are highlighted and future recommendations are provided.

摘要

在二级和三级处理的出水以及受污水影响的水体中出现新出现的污染物，如雌激素，是实施中水回用的主要障碍之一。这篇综述批判性地评估了雌激素酶降解新兴过程的性能及其效率。从同行评审文献中收集的数据表明，酶已广泛应用于（游离和固定形式）去除雌激素。其中，使用漆酶作为催化剂可以去除超过 90% 的雌激素。固定化酶可以克服游离生物催化剂的一些限制，包括可重复使用性。研究证据表明副产物的形成，例如二聚体和三聚体。尽管如此，雌激素活性评估表明酶处理后毒性降低。酶的成本和稳定性，以及它们在真实废水基质中的性能，是在废水处理中实施酶法的主要障碍。需要继续努力提高酶在废水处理行业中的成功应用。

• 强调

• 对酶支持的雌激素转化过程进行了回顾和讨论。

• 漆酶是最常用的酶，可去除超过 90% 的雌激素。

• 建议将固定作为增强雌激素去除的有效工具。

• 二聚体和三聚体已被确定为雌激素的主要生物转化产物。

• 突出了现有的研究空白，并提供了未来的建议。