反硝化菌促进硒酸盐还原研究及其应用初探

生物还原法处理水体硒污染，绿色经济。但大多数硒酸盐还原模式菌环境适应性较差，工程应用困难。采用某些具有硒酸盐还原能力的反硝化菌治理硒污染，则是一种新的尝试。以反硝化菌主导的硒酸盐还原菌群为研究对象，通过底物还原速率对比分析，结合微生物群落数据和功能基因定量，证实了Nap型硝酸盐还原酶主导了硒酸盐还原过程，明确了反硝化菌在还原硒酸盐过程中的作用，进一步拓展了硒还原菌谱。并以此为基础，提出了一种全新的硒酸盐污染治理策略:采用硝酸盐对活性污泥进行预驯化，可大大提升硒酸盐还原效率，因而具有一定的工程应用价值。

RESEARCH ON PROMOTION OF SELENIUM REDUCTION BY DENITRIFYING BACTERIA IN WASTEWATER AND ITS APPLICATION EXPLORATION

It is more economical and sustainable that using biological removal method to treat selenium pollution in water bodies. However, most selenate-reducing model bacteria strains have poor environmental adaptability and are difficult in engineering applications. Using certain denitrifying bacteria with selenate reducing ability to treat selenium pollution is a new attempt. This study focused on the selenate-reducing flora dominated by denitrifying bacteria, by using the comparative analysis of substrate reduction rate, combined with the microbial community analysis and functional gene quantification. And we confirmed that periplasmic (Nap) nitrate reductase dominated the selenite reduction, clarified the role of denitrifying bacteria in the selenate reduction process, and further enriched the selenium-reducing flora. Furthermore, we proposed a new selenate removal strategy, that was, enriching the selenate-reducing activated sludge using nitrate as electron acceptor, greatly increased the selenate reduction efficiency and was conducive to engineering application.