Xing Defeng, Cheng Shaoan, Regan John M, Logan Bruce E
Engineering Environmental Institute, and Department of Civil and Environmental Engineering, 212 Sackett Building, The Pennsylvania State University, University Park, PA 16802, USA.
Biosens Bioelectron. 2009 Sep 15;25(1):105-11. doi: 10.1016/j.bios.2009.06.013. Epub 2009 Jun 10.
Power densities produced by microbial fuel cells (MFCs) in natural systems are changed by exposure to light through the enrichment of photosynthetic microorganisms. When MFCs with brush anodes were exposed to light (4000 lx), power densities increased by 8-10% for glucose-fed reactors, and 34% for acetate-fed reactors. Denaturing gradient gel electrophoresis (DGGE) profiles based on the 16S rRNA gene showed that exposure to high light levels changed the microbial communities on the anodes. Based on 16S rRNA gene clone libraries of light-exposed systems the anode communities using glucose were also significantly different than those fed acetate. Dominant bacteria that are known exoelectrogens were identified in the anode biofilm, including a purple nonsulfur (PNS) photosynthetic bacterium, Rhodopseudomonas palustris, and a dissimilatory iron-reducing bacterium, Geobacter sulfurreducens. Pure culture tests confirmed that PNS photosynthetic bacteria increased power production when exposed to high light intensities (4000 lx). These results demonstrate that power production and community composition are affected by light conditions as well as electron donors in single-chamber air-cathode MFCs.
在自然系统中，微生物燃料电池（MFCs）产生的功率密度会因光合微生物的富集而受到光照的影响。当带有刷状阳极的MFCs暴露于光照（4000勒克斯）下时，以葡萄糖为燃料的反应器的功率密度增加了8 - 10%，以乙酸盐为燃料的反应器的功率密度增加了34%。基于16S rRNA基因的变性梯度凝胶电泳（DGGE）图谱显示，暴露于高光水平会改变阳极上的微生物群落。基于光照系统的16S rRNA基因克隆文库，以葡萄糖为燃料的阳极群落也与以乙酸盐为燃料的群落显著不同。在阳极生物膜中鉴定出了已知的外生电细菌的优势菌，包括紫色非硫（PNS）光合细菌沼泽红假单胞菌和异化铁还原细菌硫还原地杆菌。纯培养试验证实，PNS光合细菌在暴露于高光强度（4000勒克斯）时会增加产电。这些结果表明，单室空气阴极MFCs中的产电和群落组成受光照条件以及电子供体的影响。
