Enhanced remediation of PAHs-contaminated site soil by bioaugmentation with graphene oxide immobilized bacterial pellets
Enhanced remediation of PAHs-contaminated site soil by bioaugmentation with graphene oxide immobilized bacterial pellets
复制标题
通过氧化石墨烯固定细菌颗粒生物强化强化修复多环芳烃污染场地土壤
DOI：
10.1016/j.jhazmat.2022.128793
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发表时间：
2022-03-29
影响因子：
13.6
通讯作者：
Luo, Yongming
中科院分区：
文献类型：
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作者：
Ren, Wenjie;Liu, Haoran;Luo, Yongming
生物强化技术被认为是一种很有前途的多环芳烃（PAHs）净化技术，然而，可用的高效微生物制剂仍然非常有限。在此，我们通过在海藻酸-氧化石墨烯- luria - bertani培养基（LB）复合材料中嵌入高效降解细菌HPD-2，探索氧化石墨烯-固定化细菌微球（JGOLB）。采用污染场地土壤进行微观培养实验，评价JGOLB对多环芳烃的去除效果。结果表明，与传统固定化细菌微球相比，JGOLB的机械强度显著提高，比表面积更大，介孔更丰富。与传统细菌微球相比，多环芳烃的去除率显著提高了18.51%，培养35 d后，去除率达到62.86%。此外，增加的主要是高分子量多环芳烃。JGOLB不仅大大增加了土壤中嵌入降解细菌的丰度，而且显著提高了土壤中潜在的本地降解细菌（假节杆菌和节杆菌）、参与多环芳烃降解的功能基因和一些ATP转运基因的富集程度。总之，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。
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 reme-diating organic pollutants in harsh soil environment.