This study examined the removal and enantio‑specific fate of a suite of eleven chiral 2-arylpropionic acids (2-APAs) during biological wastewater treatment simulated in a laboratory-scale membrane bioreactor (MBR). Using pure (R)- and (S)- enantiomers in the MBR influent, chiral inversion was determined through the increase in the concentration of the non-dominant enantiomer and changes in the enantiomeric fraction (EF) between the two enantiomers during the treatment process. Effective (>90%) and similar removal rates between (R)- and (S)- enantiomers were confirmed for eight 2-APAs. In this study, 2-APAs exhibited diverse and distinctive chiral inversion behaviours: two 2-APAs showed (R→S) unidirectional inversion, three 2-APAs showed (S→R) unidirectional inversion, and six 2-APAs showed bidirectional inversion. This is the first study to report chiral inversion behaviours of a comprehensive suite of 2-APAs with a variety of functional groups substituted onto the aryl ring. A decrease in effluent EF over time was observed for two 2-APAs. This study shows that chiral inversion of 2-APAs varies significantly from compound to compound, despite the high similarity in their chemical structures.

本研究检查了在实验室规模的膜生物反应器 (MBR) 中模拟的废水生物处理过程中，一套 11 种手性 2-芳基丙酸 (2-APA) 的去除和对映体特异性归宿。在 MBR 进水中使用纯 ( R )- 和 ( S ) -对映异构体，通过在处理过程中非主要对映异构体浓度的增加和两种对映异构体之间对映异构分数 (EF) 的变化来确定手性转化. ( R )- 和 ( S ) -之间的有效 (>90%) 和相似的去除率八种 2-APA 的对映异构体得到确认。在这项研究中，2-APA 表现出多样化和独特的手性反转行为：两个 2-APA 显示 (R→S) 单向反转，三个 2-APA 显示 (S→R) 单向反转，六个 2-APA 显示双向反转。这是第一项报告一系列 2-APA 的手性反转行为的研究，其中各种官能团被取代到芳环上。观察到两种 2-APA 的流出物 EF 随时间下降。该研究表明，尽管化学结构高度相似，2-APA 的手性反转在化合物之间存在显着差异。