电化学产电菌的分离及性能评价

Isolation and Evaluation of Exoelectrogenic Bacteria in a Baffled Air-cathode Microbial Fuel Cell

利用兼性滚管法分离了折流板空气阴极微生物燃料电池(BAFMFC)A、B两格室的阳极生物膜,共获得19株纯菌.将菌株投加至无菌立方型反应器中,检验其产电特性.利用交流阻抗法测量各纯菌电池的内阻,结果显示38个电池的欧姆内阻为25Ω±5Ω,说明了各电池的产电差异来源于菌株本身的活性.其他运行条件均保持不变,在1000Ω外阻下,7株纯菌电池的输出电压在200mV以上.其中,A格室产电活性最高的菌株(A2)产生的最大电压为328mV,输出的最大功率密度为165.1mW/m2,B格室产电活性最高的菌株(B1)最大电压为241mV,最大功率密度为214.4mW/m2.原子力显微镜和脂肪酸快速鉴定表明,A2为肠杆菌科的杆菌,B1为厚壁菌门的芽孢杆菌.

Facultative tube methods were adopted for isolation from biofilm in two compartments of a baffled air-cathode microbial fuel cell（BAFMFC）.The separated strains were then putted into a sterile cubic MFC individually under the same condition in order to evaluate its electrogenic characteristic.Electrochemical impedance spectrometer（EIS） was employed for the internal resistance testing.It can be found that ohmic internal resistance was around 25Ω,indicating the cell performance determined only by activity of the strain.Nineteen strains were obtained,seven of which had voltages over 200 mV under 1 000Ω.The strain（A2）,owned the highest electrogenic activity in compartment A,has a voltage of 328 mV with the maximum power density 165.1 mW /m2.The maximum power density of 214.4 mW /m2 was produced by the isolate B1（the best exoelectrogenesis in compartment B）,while the maximal voltage of 241 mV was achieved.Identification of fatty acids reveals that A2 belongs to Enterobacteriaceae,and B1 belongs to the genus Bacillus.