Martelella sp. AD-3强化活性污泥耐盐降解菲效能

基于嗜盐菌Martelella sp. AD-3优配市政活性污泥搭建耐盐高效降解菲的生物反应器,在3.0 %盐度,进水菲浓度20mg/L的运行条件下,菲去除率高达97 %.批次实验证明,盐度为3.0 %,pH值为7.5~8.5,底物浓度为20~200mg/L是菲降解的最佳环境条件,此时污泥比活性高于1.0mg/(gVSS×h).各共存底物的受试浓度下,酵母提取物和苯酚促进菲降解,镉和氰化物则抑制该过程,乙酸钠、铜、铬对该过程没有明显影响.16S rRNA基因高通量测序结果表明AD-3菌在反应器内具有长期稳定性,其相对丰度维持在1.5 %.Shinella、Microbacterium和Brevundimonas是反应器中的优势菌,其相对丰度分别为20.7 %,15.1 %和11.9 %.RT-qPCR结果显示接种AD-3菌后,编码PAHs双加氧酶RHDa的功能基因差异倍数从2.1提升至11.7.

Martelella sp. AD - 3 enhanced the degradation of phenanthrene in a halotolerant activated sludge system

A halotolerant bioreactor with high efficiency degrading phenanthrene was built based on inoculating halophilic Martelella sp. AD-3 with municipal activated sludge. At the salinity of 3.0%, phenanthrene removal ratio reached 97% with influent concentration of 20mg/L. Batch experiments showed that salinity of 3.0%, pH of 7.5~8.5 and initial concentrations of 20~200mg/L are the optimal conditions for phenanthrene degradation, under which the specific activity of the sludge exceeded 1.0mg/(gVSS×h). Yeast extract and phenol can promote the degradation of phenanthrene while cadmium and cyanide would inhibit the process. Sodium acetate, copper and chromium had no obvious effect on phenanthrene degradation. 16S rRNA gene high-throughput sequencing showed that the relative abundance of strain AD-3 had long-term stability in the reactor. Shinella, Microbacterium and Brevundimonas were the dominant bacteria with their relative abundances of 20.7%, 15.1% and 11.9% respectively. RT-qPCR results showed that after inoculation with strain AD-3, the fold change of PAHs dioxygenase functional gene encoding RHDa increased from 2.1 to 11.7.