Anhui Province Key Laboratory of Farmland Ecological Conservation and Pollution Prevention, College of Resources and Environment, Anhui Agricultural University, Hefei 230036, China.
Anhui Province Key Laboratory of Farmland Ecological Conservation and Pollution Prevention, College of Resources and Environment, Anhui Agricultural University, Hefei 230036, China; CAS Key Laboratory of Urban Pollutant Conversion, Department of Environmental Science and Engineering, University of Science and Technology of China, Hefei 230026, China.
J Hazard Mater. 2024 Nov 5;479:135637. doi: 10.1016/j.jhazmat.2024.135637. Epub 2024 Aug 23.
While laccase humification has an efficient capacity to convert estrogenic pollutants, the roles of wheat (Triticum aestivum L.) root exudates (W-REs) in the enzymatic humification remain poorly understood. Herein, we presented the research into the effects of W-REs on 17β-estradiol (E2) and bisphenol A (BPA) conversion in vitro laccase humification. W-REs inhibited E2 removal but promoted BPA conversion in the enzymatic humification, and the first-order kinetic constants for E2 and BPA were 0.27-0.69 and 0.28-0.55 h, respectively. Specialized small phenols and amino acids in W-REs were susceptible to laccase humification, resulting in increased copolymerization of estrogen and W-REs. In greenhouse hydroponics, the accumulated amounts of E2 (BPA) in the roots and shoots were estimated to be 0.87 (2.15) and 0.43 (0.51) nmol·plant at day 3, respectively. By forming low- and eventually non-toxic copolymeric precipitates between estrogen and W-REs, laccase humification lowered the phytotoxicity and bioavailability of estrogen in the rhizosphere solution, consequently relieving its uptake, accumulation, and distribution in the wheat cells. This work sheds light on the roles of W-REs in regulating laccase-catalyzed estrogen humification, and gives an insight into the path of addressing organic contamination in the rhizosphere and ensuring food safety.
尽管漆酶的腐殖化具有有效转化雌激素污染物的能力，但小麦（Triticum aestivum L.）根系分泌物（W-REs）在酶促腐殖化中的作用仍知之甚少。本文研究了 W-REs 对 17β-雌二醇（E2）和双酚 A（BPA）体外漆酶腐殖化转化的影响。W-REs 抑制了 E2 的去除，但促进了 BPA 在酶促腐殖化中的转化，E2 和 BPA 的一级动力学常数分别为 0.27-0.69 和 0.28-0.55 h。W-REs 中的特殊小分子酚类和氨基酸容易被漆酶腐殖化，导致雌激素与 W-REs 的共聚增加。在温室水培条件下，第 3 天根和茎中的 E2（BPA）积累量分别估计为 0.87（2.15）和 0.43（0.51）nmol·plant。通过在雌激素和 W-REs 之间形成低毒甚至无毒的共聚物沉淀，漆酶腐殖化降低了雌激素在根际溶液中的植物毒性和生物有效性，从而减少了其在小麦细胞中的吸收、积累和分布。这项工作阐明了 W-REs 在调节漆酶催化的雌激素腐殖化中的作用，并深入了解了在根际解决有机污染和确保食品安全的途径。
