Mechanism analysis of the phytotoxicity and phytodegradation of PCBs based on the 2D-QASR model and sensitivity analysis method

Abstract

Abstract The phytotoxicity of polychlorinated biphenyls (PCBs) permanently affects the ability of plants to remediate contaminated soil. The biodegradability of PCBs in plants directly represents the effectiveness of plants to remediate contaminated soil. This paper investigates the mechanisms that affect the phytotoxicity and phytodegradation of PCBs. Besides, the corresponding improvement measures have been proposed here, which provides a theoretical basis for the research on enhanced phytoremediation of PCBs contaminated soil. The structural parameters that significantly affect the phytotoxicity and phytodegradation of PCBs have been screened by 2D-QASR models combined with sensitivity analysis method. Finally, the main parameters are regulated following a molecular dynamics approach to analyze the mitigation of the phytotoxicity of PCBs and enhancement measures of biodegradability in plants. The result shows that the 2D-QSAR model constructed in this paper meets the stability requirements. The structural parameters that significantly affect the phytotoxicity of PCBs include EHOMO, ELUMO and EG, respectively. The three structural parameters that significantly affect the biodegradability of PCBs in plants are logP, TE and IR-(C-CL)svf, respectively. According to the results of molecular dynamics verification, the addition of redox substances can mitigate the phytotoxicity of PCBs. The addition of substances that promote the affinity between PCBs and degradation enzymes can improve the biodegradability of PCBs in plants.