生物阴极微生物燃料电池中同步产电反硝化菌的分离鉴定与性能

利用反硝化筛选培养基从稳定运行的MFC-AA/O反应器阴极板上分离纯化反硝化细菌，经16S rRNA鉴定后，接种于双室MFC的阴极，测试其产电能力以筛选同步产电反硝化细菌，之后对MFC的运行温度和pH进行优化，最后通过扫描循环伏安曲线分析其产电机理。结果表明：分离获得的一株反硝化菌经鉴定为铜绿假单胞杆菌(Pseudomonas aeruginosa)，该菌可实现同步产电脱氮，最高输出电压可达168 mV左右，其脱氮反应的最优pH为7.5，最适温度为30 ℃；在生物阴极起催化产电反硝化作用的可能是Pseudomonas aeruginosa的分泌物，其作为中介体，可从电极获得电子，完成硝酸盐的还原。上述结果说明，Pseudomonas aeruginosa作为接种MFC生物阴极的纯菌，可以实现同步产电反硝化，为反硝化生物阴极MFC的实际应用奠定基础。

Isolation and identification of a simultaneous electricity production and denitrification strain in a microbial fuel cell with biocathode and its characteristics

Multiple denitrification screening mediums were used to isolate and purify denitrifying bacteria from the biocathode of a stably operated MFC-AA/O reactor, and 16S rRNA sequence analysis was conducted to identify the pure strains. The electricity production capacity was tested by inoculating the pure bacterial strains into cathodic chambers of MFCs to screen simultaneous electricity production and denitrification strains. Then, operation temperature and pH of MFC were further optimized. Finally, the electricity production mechanism was analyzed by scanning cyclic voltammetry curve. The results indicated that one isolated strain, identified as Pseudomonas aeruginosa, could achieve simultaneous electricity production and denitrification. The maximum output voltage could reach about 168 mV, and the optimum pH and temperature for denitrification were 7.5 and 30 ℃, respectively. Electrochemical analysis indicated that the simultaneous electricity production and denitrification might be catalyzed by some secretions of Pseudomonas aeruginosa, which could act as mediators to obtain electrons from the electrode and complete nitrates reduction. This study demonstrated that Pseudomonas aeruginosa as a pure electricigen inoculated in cathode chamber of MFC could achieve simultaneous electricity production and denitrification, which might lay a foundation for the practical application of MFC with denitrifying biocathode.