基因工程菌生物强化处理系统微生物群落分析

Analysis of Microbial Community in Treatment Systems Bioaugmented by Genetically Engineered Microorganism

在膜-生物反应器(MBR)和传统活性污泥反应器(CAS)中,考察了基因工程菌生物强化对阿特拉津的去除效果,并通过PCR-DGGE分析了反应器不同运行阶段污泥微生物群落的变化。结果表明,基因工程菌生物强化实现了阿特拉津的高效生物去除,MBR和CAS阿特拉津平均去除率分别达到88.6%和85.3%。阿特拉津生物强化去除有助于反应器保持较高的污泥生物活性。MBR对污染物的去除性能优于CAS。接种基因工程菌后,MBR和CAS反应器中基因工程菌密度快速下降后,逐渐保持稳定,稳定细胞密度分别为2.1×103 CFU/mL和1.7×103 CFU/mL。PCR-DGGE分析表明,MBR和CAS反应器不同运行阶段污泥微生物群落具有一定差异。阿特拉津的存在降低污泥微生物群落的种群多样性和稳定性,而阿特拉津生物强化去除使得污泥微生物群落的种群多样性和稳定性有所恢复。MBR对于保持污泥微生物群落的种群多样性和稳定性具有一定的优势。

Atrazine removal in membrane by genetically engineered microorganism bioreactor （MBR） and conventional activated sludge reactor （CAS） bioaugmented （GEM） was investigated. PCR-DGGE was used to analyze microbial community variation of both reactors in different running stages. Results indicated that high removal efficiency of atrazine was obtained in both bioreactors bioaugmented by GEM. Average removal efficiency of atrazine reached up to 88.6% in MBR and 85.3% in CAS. Atrazine removal bioaugmented by GEM would be helpful to maintain high sludge hioactivity in both bioreactors. The performance of MBR was better than CAS. GEM density decreased quickly in both bioreactors after GEM inoculation and then became stable. The stable GEM densities in MBR and CAS were 2.1×10^3 CFU/mL and 1.7×10^3 CFU/mL respectively. PCR-DGGE analysis showed microbial community variation in different running stages of two bioreactors. The biodiversity and stability of microbial community decreased in the presence of ＇atrazine and recovered after efficient atrazine removal was realized. MBR was better than CAS to maintain biodiversity and stability of microbial community.