Among three monofluoroanilines, 2-fluoroaniline (2-FA) and 3-fluoroaniline (3-FA) exhibit relatively poor biodegradability. This work examined their degradation characteristics in a mixed culture system and also analyzed the microorganism community. After acclimation for 58 d and 43 d, the high removal efficiency of 100% of 2-FA and 95.3% of 3-FA was obtained by adding 25 mg L-1 of 2-FA or 3-FA to the two reactors, respectively. In addition, the high defluorination rates of 2-FA and 3-FA were observed to be 87.0% and 89.3%, respectively. The degradation kinetics showed that the maximum specific degradation rates of 2-FA and 3-FA were (21.23 ± 0.91) mg FA (g•VSS·h)-1, and (11.75 ± 0.99) mg FA (g•VSS·h)-1, respectively. PCR-DGGE analysis revealed that the unique bacteria degrading 2-FA were mainly composed of six genera (Novosphingobium, Bradyrhizobium, Aquaspirillum, Aminobacter, Ochrobactrum, and Labrys), and five genera that degraded 3-FA (Ochrobactrum, Aquaspirillum, Lachnobacterium, Bradyrhizobium, and Variovorax). Analysis of the key catabolic enzyme activities indicated that the simultaneous hydroxylation and dehalogenation were involved in monooxygenase elimination of 2-FA and conversion of 3-FA to 4-fluorocatechol by dioxygenase, indicating that enriched mixed cultures were effective to metabolize 2-FA or 3-FA by unconventional pathways to prevent the accumulation of toxic metabolites.

中文翻译：

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混合培养系统中2-和3-氟苯胺的有氧降解和微生物群落分析。

在三种单氟苯胺中，2-氟苯胺（2-FA）和3-氟苯胺（3-FA）表现出较差的生物降解性。这项工作检查了它们在混合培养系统中的降解特性，还分析了微生物群落。适应58 d和43 d后，分别向两个反应器中添加25 mg L-1的2-FA或3-FA，可获得100％的2-FA和95.3％的3-FA的高去除效率。 。另外，观察到2-FA和3-FA的高脱氟率分别为87.0％和89.3％。降解动力学表明，2-FA和3-FA的最大比降解率分别为（21.23±0.91）mg FA（g•VSS·h）-1和（11.75±0.99）mg FA（g•VSS·h） ）-1。PCR-DGGE分析表明，降解2-FA的独特细菌主要由6个属（Novosphingobium，缓生根瘤菌，水螺旋藻，氨基杆菌、,草和拉伯斯，以及五个降解3-FA的属（O根，水螺旋藻，弹形杆菌，缓生根瘤菌和Variovorax）。对关键分解代谢酶活性的分析表明，同时羟基化和脱卤参与了2-FA的单加氧酶消除和双加氧酶将3-FA转化为4-氟邻苯二酚，表明富集的混合培养物可有效代谢2-FA或3 -FA通过非常规途径防止有毒代谢产物的积累。