College of Resources and Environment, Hunan Agricultural University, 410128 Changsha, China.
School of Environment and Energy, South China University of Technology, 510006 Guangzhou, China.
J Hazard Mater. 2023 Oct 5;459:132220. doi: 10.1016/j.jhazmat.2023.132220. Epub 2023 Aug 4.
Stenotrophomonas maltophilia J2, a highly efficient pyridine-degrading bacterium, was isolated from the aerobic tank of a pesticide-contaminated wastewater treatment plant. The strain J2 demonstrated an impressive pyridine degradation rate of 98.34% ± 0.49% within 72 h, at a pyridine concentration of 1100 mg·L, a temperature of 30 °C, a pH of 8.0, and a NaCl concentration of 0.5%. Notably, two new pyridine metabolic intermediates, 1,3-dihydroxyacetone and butyric acid, were discovered, indicating that J2 may degrade pyridine through two distinct metabolic pathways. Furthermore, the immobilized strain J2 was obtained by immobilizing J2 with biochar derived from the stem of Solidago canadensis L. In the pyridine-contaminated wastewater bioremediation experiment, the immobilized strain J2 was able to remove 2000 mg·L pyridine with a 98.66% ± 0.47% degradation rate in 24 h, which was significantly higher than that of the control group (3.17% ± 1.24%), and remained above 90% in subsequent cycles until the 27th cycle. High-throughput sequencing analysis indicated that the J2 +B group had an elevated relative abundance of bacteria and functional genes that could be associated with the degradation of pyridine. The results offer a foundation for the effective use of immobilized strain in the treatment of recalcitrant pyridine-contaminated wastewater.
嗜麦芽寡养单胞菌 J2 是一株高效降解吡啶的细菌，从农药污染的废水处理厂的好氧池中分离得到。该菌株 J2 在 1100mg·L 的吡啶浓度、30°C 的温度、8.0 的 pH 值和 0.5%的 NaCl 浓度下，72 小时内吡啶的降解率达到 98.34%±0.49%。值得注意的是，发现了两种新的吡啶代谢中间产物，1,3-二羟基丙酮和丁酸，表明 J2 可能通过两种不同的代谢途径降解吡啶。此外，通过用加拿大一枝黄花茎生物炭固定 J2 获得了固定化菌株 J2。在吡啶污染废水的生物修复实验中，固定化菌株 J2 在 24 小时内能够去除 2000mg·L 的吡啶，降解率为 98.66%±0.47%，明显高于对照组（3.17%±1.24%），并且在随后的 27 个循环中一直保持在 90%以上。高通量测序分析表明，J2+B 组中与吡啶降解相关的细菌和功能基因的相对丰度增加。该结果为固定化菌株在处理难降解吡啶污染废水中的有效应用提供了基础。
