基于高通量测序的OMS-2对序批式反应器系统微生物群落的影响

随着纳米材料的广泛应用，越来越多的纳米材料随着废水进入污水处理厂，纳米材料对污水生物处理系统的潜在影响越来越受到重视。探讨了氧化锰八面体分子筛(manganese oxide octahedral molecular sieve, OMS-2)纳米颗粒对序批式反应器(sequencing batch reactor，SBR)中活性污泥微生物群落结构的影响；以活性艳红X-3B溶液模拟印染废水，将不同浓度的OMS-2混入稳定运行的SBR中，采用Illumina MiSeq高通量测序分析技术，对不同SBR中微生物分布规律进行了研究。结果表明：SBR添加0.25 g·L⁻¹的OMS-2后，其COD去除率和脱色率分别提升了6%和13.6%；Illumina MiSeq高通量测序显示，在混入0.25 g·L⁻¹的OMS-2后，SBR内污泥菌群中拟杆菌门(Bacteroidetes)和变形菌门(Proteobacteria)的微生物DNA序列操作分类单元(operational taxonomic units，OTU)分别增加了16.8%和96.4%，这2类菌种可能提升了SBR降解有机污染物的能力；不同浓度的OMS-2改变了菌群的多样性和结构，低浓度的OMS-2可以提升微生物菌群的多样性和改变菌群的结构。X射线光电子能谱(XPS)分析表明，OMS-2在SBR中存在锰(Ⅳ)/锰(Ⅲ)转变为锰(Ⅱ)的氧化还原反应，该过程可能影响了菌群的组成。研究为纳米材料的实际应用和环境风险提供了参考。

Effect of OMS-2 on microbial community of SBR system through high-throughput sequencing

With widely using of the nano-particles, more and more nano-particles have entered the sewage treatment plant with wastewater, and more and more attentions have been paid to the potential impact of nano-particles on sewage biological treatment system. In this study, the effects of nano manganese oxide octahedral molecular sieve (OMS-2) nanoparticles on the microbial community in activated sludge of sequencing batch reactor (SBR). The dyeing and printing wastewater was simulated by X-3B, and different dosages of nano OMS-2 were added into SBR. The microbial distribution rules in different SBRs were studied by the Illumina MiSeq high-throughput sequencing of 16S rRNA gene. Results showed that the COD removal and decolorization increased by 6% and 13.6%, respectively, at OMS-2 dosage of 0.25 g·L−1 in the SBR, and the OTU of Bacteroidetes and Proteobacteria increased by 16.8% and 96.4%, respectively, based on the Illumina MiSeq high-throughput sequencing of 16S rRNA gene, and these two types of microorganisms could enhance the ability of organic pollutants degradation by SBR. Moreover, the small dosage of nano OMS-2 could enhance the microbial diversity and alter the community structure. The X-ray photoelectron spectroscopy illustrated that the redox reaction of Mn(Ⅳ)/Mn(Ⅲ) to Mn(Ⅱ) in nano OMS-2 occurred in the SBR, and in turn affected the microbial community. This study provides innovative ideas for the practical application of nano-particles and their environmental risks assesment.