The present work evaluates the action of nitroreductase enzyme immobilized on Tosylactivated magnetic particles (MP-Tosyl) on three disperse dyes which contain nitro and azo groups. The dyes included Disperse Red 73 (DR 73), Disperse Red 78 (DR 78), and Disperse Red 167 (DR 167). The use of a magnet enabled the rapid and easy removal of the immobilized enzyme after biotransformation; this facilitated the identification of the products generated using high-performance liquid chromatography with diode array detector (HPLC-DAD) and mass spectrometry (LC-MS/MS). The main products formed by the in vitro biotransformation were identified as the product of nitro group reduction to the correspondent amine groups, which were denoted as follows: 50% of 2-(2-(4-((2-cyanoethyl)(ethyl)amino)phenyl)hydrazinyl)-5-nitrobenzonitrile, 98% of 3-((4-((4-amino-2-chlorophenyl) diazenyl)phenyl) (ethyl)amino)propanenitrile and 99% of (3-acetamido-4 - ((4-amino-2-chlorophenyl) diazenyl) phenyl) azanediyl) bis (ethane-2,1-diyl) for DR 73, DR 78 and DR 167, respectively. Based on the docking studies, the dyes investigated were found to be biotransformed by nitroreductase enzyme due to their favorable interaction with the active site of the enzyme. Theoretical results show that DR73 dye exhibits a relatively lower rate of degradation; this is attributed to the cyanide substituent which affects the electron density of the azo group. The docking studies also indicate that all the dyes presented significant reactivity towards DNA. However, Disperse Red 73 was found to exhibit a substantially higher reactivity compared to the other dyes; this implies that the dye possesses a relatively higher mutagenic power. The docking results also show that DR 73, DR 78 and DR 167 may be harmful to both humans and the environment, since the mutagenicity of nitro compounds is associated with the products formed during the reduction of nitro groups. These products can interact with biomolecules, including DNA, causing toxic and mutagenic effects.

本工作评估了固定在Tosyl活化的磁性粒子（MP-Tosyl）上的三种含有硝基和偶氮基团的分散染料上的硝基还原酶的作用。染料包括分散红73（DR 73），分散红78（DR 78）和分散红167（DR 167）。磁铁的使用使生物转化后的固定化酶能够快速，轻松地去除。这有助于鉴定使用带有二极管阵列检测器（HPLC-DAD）和质谱（LC-MS / MS）的高效液相色谱法生成的产物。体外形成的主要产品生物转化被确定为硝基还原成相应胺基的产物，其表示如下：2-（2-（4-（（（2-氰基乙基）（乙基）氨基）苯基）肼基）-5％ -硝基苄腈，3-（（4-（（4-氨基-2-氯苯基）二氮烯基）苯基）（乙基）氨基）丙腈的98％和（3-乙酰氨基-4-（（4-氨基-2 -氯苯基）二氮烯基）苯基）氮杂二基）双（乙烷-2,1-二基）分别用于DR 73，DR 78和DR 167。基于对接研究，发现所研究的染料由于其与酶的活性位点的良好相互作用而被硝基还原酶生物转化。理论结果表明，DR73染料的降解速率相对较低。这归因于氰化物取代基影响了偶氮基团的电子密度。对接研究还表明，所有染料都对DNA具有显着的反应性。但是，发现分散红73与其他染料相比，具有显着更高的反应性。这意味着该染料具有相对较高的诱变能力。对接结果还表明DR 73，DR 78和DR 167可能对人类和环境均有害，因为硝基化合物的诱变性与硝基还原过程中形成的产物有关。这些产品可与生物分子（包括DNA）相互作用，引起毒性和诱变作用。对接结果还表明DR 73，DR 78和DR 167可能对人类和环境均有害，因为硝基化合物的诱变性与硝基还原过程中形成的产物有关。这些产品可与生物分子（包括DNA）相互作用，引起毒性和诱变作用。对接结果还表明DR 73，DR 78和DR 167可能对人类和环境均有害，因为硝基化合物的诱变性与硝基还原过程中形成的产物有关。这些产品可与生物分子（包括DNA）相互作用，引起毒性和诱变作用。