In this study, the transformation and detoxification of sulfamethoxazole (SMX, a frequently detected antibiotic in the environments) by permanganate (Mn(VII)) in the presence of model humic constituents (HCs) was evaluated. SMX that hardly react to Mn(VII) was rapidly degraded by Mn(VII) in the presence of catechol (CAT) at pH 5-7, while resorcinol (RES) and hydroquinone (HQ) showed negligible accelerating effect. This enhancing effect was attributed to the 1,4-nucleophilic addition between SMX and o-benzoquinone (o-BQ), an important intermediate generated from oxidation of CAT by Mn(VII). Both Mn(VII) and in-situ formed manganese dioxide (Mn(IV)) accounted for the generation of o-BQ. The experimental results indicated that alkaline condition and excess Mn(VII) were unfavorable for the degradation of SMX by inhibiting the formation of o-BQ. Bioluminescence inhibition assay with vibrio fischeri and data simulated by EPI software showed that the transformation products of SMX retained much less acute toxicity than the parent SMX. Furthermore, the effect of several other HCs structurally related to CAT on the abatement of SMX was explored. The result suggested that the accelerating effect of CAT analogues largely depended on the type of substituent group in para position. Meanwhile, the concentration of manganese in the supernatant was lower than WHO criteria (0.1mg/L). This work provided a novel and efficiency strategy to detoxify SMX in water treatment.

在这项研究中，评估了在模型腐殖质成分（HCs）存在下高锰酸盐（Mn（VII））对磺胺甲恶唑（SMX，在环境中经常检测到的抗生素）的转化和解毒作用。在pH 5-7的邻苯二酚（CAT）存在下，几乎不与Mn（VII）反应的SMX被Mn（VII）迅速降解，而间苯二酚（RES）和对苯二酚（HQ）的加速作用可忽略不计。这种增强作用归因于SMX和邻苯醌（o- BQ）之间的1,4-亲核加成，邻苯醌是Mn（VII）氧化CAT产生的重要中间体。Mn（VII）和原位形成的二氧化锰（Mn（IV））都导致了邻-BQ。实验结果表明，碱性条件和过量的Mn（VII）通过抑制o- BQ的形成不利于SMX的降解。用费氏弧菌进行的生物发光抑制试验和EPI软件模拟的数据表明，SMX的转化产物保留的急性毒性比母体SMX少得多。此外，还探讨了与CAT结构相关的其他几种HC对减少SMX的影响。结果表明CAT类似物的加速效果主要取决于取代基的类型对位置。同时，上清液中的锰浓度低于WHO标准（0.1mg / L）。这项工作为水处理中的SMX排毒提供了一种新颖而有效的策略。