Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China.
Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China.
J Hazard Mater. 2022 Jul 5;433:128793. doi: 10.1016/j.jhazmat.2022.128793. Epub 2022 Mar 26.
Bioaugmentation is considered as a promising technology for cleanup of polycyclic aromatic hydrocarbons (PAHs) from contaminated site soil, however, available high-efficiency microbial agents remain very limited. Herein, we explored graphene oxide (GO)-immobilized bacterial pellets (JGOLB) by embedding high-efficiency degrading bacteria Paracoccus aminovorans HPD-2 in alginate-GO-Luria-Bertani medium (LB) composites. Microcosm culture experiments were performed with contaminated site soil to assess the effect of JGOLB on the removal of PAHs. The results showed that JGOLB exhibited greatly improved mechanical strength, larger specific surface area and more enriched mesopores, compared with traditional immobilized bacterial pellets. They significantly increased the removal rate of PAHs by 18.51% compared with traditional bacterial pellets, reaching the removal rate at 62.86% over 35 days of incubation. Moreover, the increase mainly focused on high-molecular-weight PAHs. JGOLB not only greatly increased the abundance of embedded degrading bacteria in soil, but also significantly enhanced the enrichment of potential indigenous degrading bacteria (Pseudarthrobacter and Arthrobacter), the functional genes involved in PAHs degradation and a number of ATP transport genes in the soil. Overall, such nanocomposite bacterial pellets provide a novel microbial immobilization option for remediating organic pollutants in harsh soil environment.
生物强化被认为是一种有前途的技术，可用于清除污染土壤中的多环芳烃（PAHs），然而，可用的高效微生物剂仍然非常有限。在此，我们通过将高效降解菌假单胞菌属 HPD-2 嵌入藻酸盐-氧化石墨烯- LB 复合材料中，探索了氧化石墨烯（GO）固定化细菌颗粒（JGOLB）。通过微宇宙培养实验，用污染场地土壤评估 JGOLB 对 PAHs 去除的效果。结果表明，与传统固定化细菌颗粒相比，JGOLB 表现出了更高的机械强度、更大的比表面积和更丰富的中孔，显著提高了 PAHs 的去除率，比传统细菌颗粒提高了 18.51%，在 35 天的培养过程中达到了 62.86%的去除率。此外，这种提高主要集中在高分子量 PAHs 上。JGOLB 不仅大大增加了土壤中嵌入降解菌的丰度，而且还显著增强了潜在土著降解菌（节杆菌属和葡萄球菌属）、PAHs 降解相关功能基因和一些 ATP 转运基因的富集。总的来说，这种纳米复合细菌颗粒为修复恶劣土壤环境中的有机污染物提供了一种新的微生物固定化选择。
