投加甲醇对工业园区污水处理厂菌群及ARGs的影响

EFFECT OF ADDING METHANOL ON MICROBIAL COMMUNITIES AND ARGs IN A WASTEWATER TREATMENT PLANT OF AN INDUSTRIAL PARK

甲醇被广泛用作为提高低碳氮比污水处理效果时使用的外加碳源,但其对工业园区污水处理,特别是抗生素抗性基因(ARGs)影响的报道较少。通过16S rRNA高通量测序和宏基因组测序等方法,对投加甲醇新疆某工业园区污水厂(采用氧化沟+MBR工艺)的处理效果、功能微生物丰度和ARGs变化进行了研究。结果表明:甲醇的投加使该工业园区污水厂出水稳定达到GB 18918—2002《城镇污水处理厂污染物排放标准》中一级A标准;具有降解甲基功能的unclassified_c_Gammaproteobacteria和具有反硝化功能的生丝菌属(Hyphomicrobium)在活性污泥中相对丰度分别高达31.92%和28.68%;进水中ARGs为150.77×10^(-6),出水ARGs下降到25.77×10^(-6)。研究结果有助于人们深入认识甲醇在工业园区污水处理过程中的作用,并为工业园区污水处理过程新污染物ARGs的控制提供数据支持和理论指导。

Methanol is widely used as a carbon source to improve the efficiency of wastewater treatment with a low carbon to nitrogen ratio.However,the influences of methanol addition on treatment efficiency of the water treatment facilities in the industrial parks are still rarely reported and unsufficiently understood,especially for the changes in antibiotic resistance genes(ARGs).Here,high-throughput sequencing and metagenomic sequencing methods were employed to reveal the treatment effects using oxidation ditch+MBR process with methanol addition,and the changes in the relative abundance of functional microorganisms and ARGs in a waste water treatment plant of an industrial park in Xinjiang.The results showed that methanol addition improved the effluent quality to consistently meet the class A of the Discharge Standard of Pollutants for Municipal Wastewater Treatment Plants(GB 18918—2002).Furthermore,we found that the relative abundance of unclassified_c_Gammaproteobacteria with methyl degrading function,and Hyphomicrobium with denitrifying function in activated sludge was improved to 31.84%and 28.68%,respectively.More importantly,the total ARGs in the influent were 150.77×10^(-6),but decreased to 25.77×10^(-6)in the effluent,indicating that methanol addition significantly reduced ARGs.In summary,these results shed light on understanding the roles of methanol addition in the wastewater treatment process,and further provide data support and theoretical guidance for the controlling of new pollutants ARGs in the industrial parks.