College of Bioscience and Biotechnology, Jiangxi Agricultural University, Jiangxi Engineering Laboratory for the Development and Utilization of Agricultural Microbial Resources, Nanchang 330045, PR China; Jiangxi Key Laboratory for Conservation and Utilization of Fungal Resources, Jiangxi Agricultural University, Nanchang 330045, PR China.
College of Bioscience and Biotechnology, Jiangxi Agricultural University, Jiangxi Engineering Laboratory for the Development and Utilization of Agricultural Microbial Resources, Nanchang 330045, PR China; Jiangxi Key Laboratory for Conservation and Utilization of Fungal Resources, Jiangxi Agricultural University, Nanchang 330045, PR China.
J Hazard Mater. 2021 Mar 15;406:124285. doi: 10.1016/j.jhazmat.2020.124285. Epub 2020 Oct 28.
There is a great need for efficiently treating papermaking black liquor because it can seriously pollute both soil and water ecosystems. In this study, the Plackett-Burman (PB) experimental design combined with response surface methodology (RSM) was used for improving the biodegradation efficiency of lignin by a new isolated thermophilic and alkali-tolerant strain Serratia sp. AXJ-M, and the results showed that a biodegradation efficiency of 70.5% was achieved under optimal culture conditions. The bacterium with ligninolytic activities significantly decreased target the parameters (color 80%, lignin 60%, phenol 95%, BOD 80% and COD 80%). The control and treated samples were analyzed by gas chromatography-mass spectrometer (GC-MS), which showed that the concentrations of a majority of low-molecular-weight compounds were decreased after biological treatment. Furthermore, toxicological, genotoxicity and phytotoxicity studies have supported the detoxification by the bacterium of black liquor. Finally, the genome sequence of the thermophilic, alkali-tolerant and lignin-degrading bacterium AXJ-M was completed, and the genetic basis of the thermophilic and alkali-resistant properties of AXJ-M was preliminarily revealed. The dyp-type peroxidase was first reported to have the potential to catalyze lignin degradation structurally. These findings suggest that Serratia sp. AXJ-M may be potentially useful for bioremediation applications for papermaking black liquor.
造纸黑液的处理非常重要，因为它会严重污染土壤和水生态系统。在这项研究中，采用 Plackett-Burman (PB) 实验设计结合响应面法 (RSM) 对一株新分离的嗜热耐碱菌 Serratia sp. AXJ-M 进行优化，以提高木质素的生物降解效率，结果表明在最佳培养条件下生物降解效率达到 70.5%。具有木质素降解活性的细菌显著降低了目标参数（颜色 80%、木质素 60%、苯酚 95%、BOD 80%和 COD 80%）。通过气相色谱-质谱联用仪 (GC-MS) 对对照和处理样品进行分析，结果表明生物处理后大多数低分子量化合物的浓度降低。此外，毒理学、遗传毒性和植物毒性研究支持了细菌对黑液的解毒作用。最后，完成了嗜热、耐碱和木质素降解菌 AXJ-M 的基因组序列，初步揭示了 AXJ-M 嗜热和耐碱特性的遗传基础。首次报道 dyp 型过氧化物酶具有结构上催化木质素降解的潜力。这些发现表明，Serratia sp. AXJ-M 可能在造纸黑液的生物修复应用中具有潜在的应用价值。
