State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu 210023, P. R. China.
Environ Sci Process Impacts. 2017 Apr 19;19(4):596-604. doi: 10.1039/c6em00703a.
In this study, we examined the fate and transformation of tetrabromobisphenol A (TBBPA), mediated by the representative oxidoreductases (laccase and horseradish peroxidase (HRP)) in natural waters. Both enzymes could readily degrade TBBPA at environmentally relevant concentrations (e.g., 10 nmol L) in natural waters. After 2 hour treatment, 0.5-25% and 35-65% of TBBPA were degraded in municipal wastewater and natural surface waters by a laccase or HRP-catalyzed reaction, respectively. Enzyme kinetics evaluations indicated that the k/K ratio of HRP (1.01 μM s) was much higher than that of laccase (0.032 μM s) for TBBPA degradation, suggesting that the catalytic performance of HRP towards TBBPA was more efficient than that of laccase. The effects of pH and organic matter on the enzymatic degradation efficiency were explored. Organic matter in the water inhibited the enzymatic degradation efficiency and the degree of inhibition was proportional to the UV values of water. Product identification indicated that the product distribution of TBBPA at low concentration (10 nmol L) was similar to that of TBBPA at high concentration (10 μmol L). The degradation intermediates underwent further enzymatic reaction to yield higher molecular weight secondary products. Toxicity assessment showed that TBBPA toxicity was effectively eliminated by the oxidoreductase-catalyzed reaction.
在这项研究中，我们考察了四溴双酚 A（TBBPA）在天然水中代表性氧化还原酶（漆酶和辣根过氧化物酶（HRP））介导下的命运和转化。两种酶都可以在天然水中环境相关浓度（例如 10 nmol L）下快速降解 TBBPA。经过 2 小时的处理，在城市废水中，TBBPA 分别通过漆酶或 HRP 催化反应被降解了 0.5-25%和 35-65%；在天然地表水中，TBBPA 分别被降解了 0.5-25%和 35-65%。酶动力学评价表明，HRP（1.01 μM s）对 TBBPA 降解的 k/K 比值远高于漆酶（0.032 μM s），这表明 HRP 对 TBBPA 的催化性能比漆酶更有效。还探索了 pH 值和有机物对酶促降解效率的影响。水中的有机物抑制了酶促降解效率，抑制程度与水的 UV 值成正比。产物鉴定表明，TBBPA 在低浓度（10 nmol L）时的产物分布与高浓度（10 μmol L）时的产物分布相似。降解中间体进一步进行酶反应，生成更高分子量的次级产物。毒性评估表明，TBBPA 的毒性通过氧化还原酶催化反应得到有效消除。
