利用MFC阳极室暗发酵培养沼泽红假单胞菌

Dark culture of Rhodopseudomonas palustris using MFC reactor

为了克服光合细菌光培养时的光衰减及高能耗等问题,考查了将微生物燃料电池(MFC)作为培养装置黑暗培养光合细菌的可行性。结果表明,MFC有利于菌株W1的优势生长,接种3 d后MFC内光合细菌浓度即可达到715 mg/L,而空白系统中不到308 mg/L。荧光原位杂交分析表明,MFC体系中的杂菌含量小于4%,远低于空白的33%。利用MFC进行光合细菌培养时,最大输出电压和最大输出功率可分别达到487 mV和56 mW/m2。MFC促进光合细菌生长的原因可能在于对体系兼氧环境的维持,在MFC体系中氧化还原电位始终处于200^-300 mV之间,有利于兼氧光合细菌的优势生长。

To solve the problems of light attenuation and high-energy cost during cultivation of photosynthetic bacteria,we investigated the feasibility whether microbial fuel cell( MFC) can be used as the cultivation device for dark culture of Rhodopseudomonas palustris W1. The investigation results showed that the biomass of strain W1 reached 715 mg /L in the MFC and was below 308 mg /L in control reactor after 3-d growth. Thus,the MFC is conducive to the dominant growth of strain W1. Fluorescent in situ hybridization analysis revealed that the composition percentage of contaminating bacteria was lower than 4% in MFC and higher than 33% in control reactor. During the cultivation of photosynthetic bacteria,the obtained maximum voltage and power density of MFC were 487 mV and 56 mW /m2,respectively. Moreover,the function that MFC promotes the dominant growth of strain W1 can be interpreted as follows: MFC is able to maintain anoxic environment for the dominant growth of photosynthetic bacteria( an oxidation reduction potential in a range from 200 to- 300 mV).