Department of Biological Engineering, Seokyeong University, Seoul 136-704, Korea.
J Microbiol Biotechnol. 2009 Dec;19(12):1665-71. doi: 10.4014/jmb.0904.04002.
Anaerobic digestion sludge was cultivated in an electrochemical bioreactor (ECB) to enrich the hydrogenotrophic methanogens. A modified graphite felt cathode with neutral red (NR-cathode) was charged with electrochemical reducing power generated from a solar cell. The methane and carbon dioxide collected in a Teflon bag from the ECB were more than 80 ml/l of reactant/day and less than 20 ml/l of reactant/day, respectively, whereas the methane and carbon dioxide collected from a conventional bioreactor (CB) was around 40 ml/l of reactant/day, respectively. Moreover, the maximal volume ratios of methane to carbon dioxide (M/C ratio) collected in the Teflon bag from the ECB and CB were 7 and 1, respectively. The most predominant methanogens isolated from the CB on the 20th, 80th, and 150th days of incubation were hydrogenotrophs. The methanogenic diversity analyzed by temperature gradient gel electrophoresis (TGGE) of the 16S rDNA variable region was higher in the ECB than in the CB. The DNA extracted from the TGGE bands was more than 95% homologous with hydrogenotrophic methanogens in the CB. In conclusion, the ECB was demonstrated as a useful system for enriching hydrogenotrophic methanogens and increasing the M/C ratio of the gas product.
在电化学生物反应器（ECB）中培养厌氧消化污泥，以富集产氢甲烷菌。带有中性红（NR-阴极）的改良石墨毡阴极接受来自太阳能电池的电化学还原力。从 ECB 收集的甲烷和二氧化碳在特氟龙袋中分别超过 80ml/l 的反应物/天和小于 20ml/l 的反应物/天，而从传统生物反应器（CB）收集的甲烷和二氧化碳分别约为 40ml/l 的反应物/天。此外，从 ECB 和 CB 的特氟龙袋中收集的甲烷与二氧化碳的最大体积比（M/C 比）分别为 7 和 1。在培养的第 20、80 和 150 天，从 CB 分离出的最主要的产甲烷菌是产氢菌。通过 16S rDNA 可变区的温度梯度凝胶电泳（TGGE）分析的产甲烷菌多样性在 ECB 中高于 CB。从 TGGE 条带中提取的 DNA与 CB 中的产氢产甲烷菌具有 95%以上的同源性。总之，ECB 被证明是一种有用的系统，可以富集产氢产甲烷菌并提高气体产物的 M/C 比。
