School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou, 215009, China.
School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou, 215009, China.
J Environ Manage. 2021 Nov 1;297:113415. doi: 10.1016/j.jenvman.2021.113415. Epub 2021 Jul 29.
In this study, the biodegradation of polycyclic aromatic hydrocarbons (PAHs) in soil washing solution containing Tween 80 was conducted using native mixed bacteria (Pseudomonas sp. Z1, Sphingobacterium sp. Z2, and Klebsiella sp. K) embedded in polyvinyl alcohol-sodium alginate-nano alumina (PVA-SA-ALNPs) gel beads. The optimal dosage of immobilized beads and embedded biomass for the biodegradation of phenanthrene (PHE), fluoranthene (FLU), and pyrene (PYR) were 10 % (v/v) and 20 % (v/v), respectively. SEM analysis showed that the porous structure of the immobilized beads was a cross-linked network with abundant pores that provided many potential adhesion sites for microorganisms. The beads with the immobilized mixed bacteria maintained a high activity during batch experiments and could even be reused for 3 cycles (90 d). Compared with the beads containing individual immobilized strain, the immobilized mixed bacteria showed a more efficient biodegradation of PHE (91.67 %), FLU (88.6 %), and PYR (88.5 %) in synthetic soil washing effluent within 30 d. The first-order kinetic model suitably described the degradation process of the three target PAHs. By adding Tween 80 to the synthetic eluent, the degradation of PHE, FLU, and PYR increased by 16.39 %, 22.25 %, and 21.29 %, respectively, indicating that Tween 80 promoted PAHs biodegradation, even though it was also rapidly degraded during the reaction cycle. These findings suggest that the developed mixed bacteria embedded in PVA-SA-ALNPs gel beads has great potential for PAHs remediation.
在这项研究中，使用包埋在聚乙烯醇-海藻酸钠-纳米氧化铝（PVA-SA-ALNPs）凝胶珠中的土著混合细菌（假单胞菌 Z1、鞘氨醇杆菌 Z2 和克雷伯氏菌 K），在含有吐温 80 的土壤洗脱液中进行了多环芳烃（PAHs）的生物降解。固定化珠的最佳剂量和包埋生物量用于生物降解菲（PHE）、荧蒽（FLU）和芘（PYR）分别为 10%（v/v）和 20%（v/v）。SEM 分析表明，固定化珠的多孔结构是一种具有丰富孔的交联网络，为微生物提供了许多潜在的附着位点。含有固定化混合细菌的珠在批量实验中保持了较高的活性，甚至可以重复使用 3 次（90 天）。与含有单个固定化菌株的珠相比，固定化混合细菌在 30 天内更有效地生物降解了合成土壤洗脱液中的 PHE（91.67%）、FLU（88.6%）和 PYR（88.5%）。一级动力学模型适合描述三种目标 PAHs 的降解过程。通过向合成洗脱液中添加吐温 80，PHE、FLU 和 PYR 的降解分别增加了 16.39%、22.25%和 21.29%，表明吐温 80 促进了 PAHs 的生物降解，尽管它在反应循环中也迅速降解。这些发现表明，包埋在 PVA-SA-ALNPs 凝胶珠中的开发混合细菌具有修复 PAHs 的巨大潜力。
