We report results of the studies relating to improved stability (40 days) of small sized microbial fuel cell (MFC) fabricated using agarose embedded paper-based proton exchange membrane. A fermentative bacterium Providencia rettgeri was isolated from rotten potato slurry and identified by 16S rRNA sequencing. The electroactivity of the bacteria was monitored via chronoamperometric and cyclic voltammetric studies using a three-electrode system which indicated the presence of bacterial redox mediator. The Matrix-Assisted Laser Desorption/Ionization-Time of Flight (MALDI-TOF) and UV–Vis absorption spectroscopy provided the evidence that Providencia rettgeri synthesized folate (vitamin B₉) during fermentation that was found to act for the first time as a redox mediator in an MFC. The paper based designed MFC fed with Providencia rettgeri yielded open circuit voltage of 787.9 mV with power and current density of 5.02 W/m³ and 11.26 A/m³, respectively when measured across 10 kΩ. The microbial re-chargeable battery comprising of an assembly of parallelly aligned four units of MFCs when connected in series (total 16 MFCs), generated 1.5 V that was used for powering a red-light emitting device (LED).

我们报告有关使用琼脂糖嵌入式纸质子交换膜制造的小型微生物燃料电池（MFC）的稳定性（40天）改善的研究结果。从腐烂的马铃薯泥中分离出发酵菌普罗维登斯氏菌，并通过16S rRNA测序进行鉴定。使用三电极系统通过计时安培法和循环伏安法研究监测细菌的电活性，这表明存在细菌氧化还原介体。基质辅助激光解吸/电离飞行时间（MALDI-TOF）和UV-Vis吸收光谱法提供了普罗维登斯氏菌合成叶酸（维生素B ₉）在发酵过程中被发现首次在MFC中充当氧化还原介体。当在10kΩ上测量时，基于纸质设计的MFC供给了Providencia rettgeri，其开路电压为787.9 mV，功率和电流密度分别为5.02 W / m ³和11.26 A / m ³。当串联连接时，由可并联排列的四个单元的MFC组件组成的微生物可充电电池（总共16个MFC）产生的1.5 V电压用于为红色发光器件（LED）供电。