School of Environmental Science and Engineering, Tianjin University, 92 Weijin Road, Tianjin 300072, China.
School of Environmental Science and Engineering, Tianjin University, 92 Weijin Road, Tianjin 300072, China.
Sci Total Environ. 2023 Dec 20;905:167305. doi: 10.1016/j.scitotenv.2023.167305. Epub 2023 Sep 22.
Polycyclic aromatic hydrocarbons (PAHs) are highly toxic organic pollutants widely distributed in terrestrial environments and laccase was considered as an effective enzyme in PAHs bioremediation. However, laccase-assisted phytoremediation of PAHs-contaminated soil has not been reported. Moreover, the overuse of plastic films in agriculture greatly increased the risk of co-existence of PAHs and microplastics in soil. Microplastics can adsorb hydrophobic organics, thus altering the bioavailability of PAHs and ultimately affecting the removal of PAHs from soil. Therefore, this study aimed to evaluate the efficiency of laccase-assisted maize (Zea mays L.) in the remediation of phenanthrene (PHE)-contaminated soil and investigate the effect of microplastics on this remediation process. The results showed that the combined application of laccase and maize achieved a removal efficiency of 83.47 % for soil PHE, and laccase significantly reduced the accumulation of PHE in maize. However, microplastics significantly inhibited the removal of soil PHE (10.88 %) and reduced the translocation factor of PHE in maize (87.72 %), in comparison with PHE + L treatment. Moreover, microplastics reduced the laccase activity and the relative abundance of some PAHs-degrading bacteria in soil. This study provided an idea for evaluating the feasibility of the laccase-assisted plants in the remediation of PAHs-contaminated soil, paving the way for reducing the risk of secondary pollution in the process of phytoremediation.
多环芳烃（PAHs）是一种广泛分布于陆地环境中的高毒性有机污染物，漆酶被认为是 PAHs 生物修复中的一种有效酶。然而，漆酶辅助植物修复 PAHs 污染土壤的方法尚未见报道。此外，农业中大量使用塑料薄膜大大增加了 PAHs 和土壤中微塑料共存的风险。微塑料可以吸附疏水性有机物，从而改变 PAHs 的生物可利用性，并最终影响土壤中 PAHs 的去除。因此，本研究旨在评估漆酶辅助玉米（Zea mays L.）修复菲（PHE）污染土壤的效率，并研究微塑料对这一修复过程的影响。结果表明，漆酶和玉米的联合应用对土壤 PHE 的去除效率达到了 83.47%，漆酶显著降低了 PHE 在玉米中的积累。然而，与 PHE+L 处理相比，微塑料显著抑制了土壤 PHE 的去除（10.88%），并降低了 PHE 在玉米中的迁移因子（87.72%）。此外，微塑料降低了土壤中的漆酶活性和一些 PAHs 降解菌的相对丰度。本研究为评估漆酶辅助植物修复 PAHs 污染土壤的可行性提供了思路，为减少植物修复过程中二次污染的风险铺平了道路。
