Dang Shuxian, Fan Weihua, Meng Fanyun, Li Xiangjin, Hao Jiuxiao, Wang Chongyang
Miami College, Henan University, Kaifeng, Henan Province, China, 475000.
School of Environment, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou, China, 310000.
Chemosphere. 2024 Sep;363:142957. doi: 10.1016/j.chemosphere.2024.142957. Epub 2024 Jul 31.
Azo dye-containing sewage is commonly detected at high salinity, temperature and pH. In this study, a halo-thermoalkalophilic azo dye decolorization consortium was enriched and named "consortium HL". Consortium HL which was dominated by Marinobacter (84.30%), Desulfocurvibacter (1.89%), and Pseudomonas (1.85%), was able to completely decolorize Direct Blue 5B (DB5) during incubation with the material at 5% salinity, 50 °C, and pH 9 for 30 h. The decolorization mechanism was proposed based on combined metagenomic analysis, GC‒MS, and enzymatic activity detection. The action of the consortium HL showed great tolerance to variations in salinity, temperature and pH. A phytotoxicity study indicated that the metabolic intermediates showed no significant toxicity to the generation of Cucumis sativus and Oryza sativa seeds. This study, in which azo dye decolorization and degradation under high-salt, high-temperature and high-alkalinity conditions were investigated and deeply analyzed by metagenomic information, is the first report regarding the ability of Marinobacter to decolorize azo dyes at high temperatures.
含偶氮染料的污水通常在高盐度、高温和高pH值条件下被检测到。在本研究中，富集了一个嗜盐嗜热嗜碱偶氮染料脱色菌群，并将其命名为“菌群HL”。以海杆菌属（84.30%）、脱硫弯杆菌属（1.89%）和假单胞菌属（1.85%）为主的菌群HL，在5%盐度、50℃和pH 9条件下与材料孵育30小时期间，能够使直接蓝5B（DB5）完全脱色。基于宏基因组分析、气相色谱-质谱联用（GC-MS）和酶活性检测，提出了脱色机制。菌群HL的作用表现出对盐度、温度和pH值变化的高度耐受性。一项植物毒性研究表明，代谢中间体对黄瓜和水稻种子的萌发没有显著毒性。本研究通过宏基因组信息对高盐、高温和高碱条件下偶氮染料的脱色和降解进行了研究和深入分析，是关于海杆菌属在高温下对偶氮染料脱色能力的首次报道。
