以课题组前期筛选得到的菌株Tolumonas osonensis P2-A-1为对象,通过菌体初始浓度、底物种类和浓度、阳极液pH、外电阻等参数的优化以及细胞的通透化处理,提高其在微生物燃料电池中的产电性能。结果表明,菌株T. osonensis P2-A-1接种到TSB液体培养基中,22℃有氧条件下静置培养48 h (OD 600=2.714),离心收集的菌体经1 mmol?L?1 EDTA处理20 min后,接种到阳极液Ⅱ(PBBM液体培养基中加入终浓度为2.000 g?L?1的乙酸钠(作为底物)和终浓度为5.000 g?L?1的柠檬酸铁,pH 7.2),制备得到细胞浓度为3.394 g?L?1的接种液,注入MFCs反应器,外接1000Ω电阻,于室温下运行14 d,功率密度达到509 mW?m?2,比优化前提高了162.4%。这是首次对T. osonensisa种内微生物产电性能及其在微生物燃料电池中应用的报道。其成果对于丰富产电微生物的多样性,挖掘更多具有高电化学活性的微生物纯种、提高其产电性能具有重要的指导意义。
Power generation performance of Tolumonas osonensis P2-A-1 in MFCs was improved by optimizing initial cell concentration in inoculation medium, substrate type and concentration, anolyte pH, external resistance, and chemical solvent permeabilization. The optimized experimental condition is inoculation in TSB liquid medium and statically incubated at 22℃ under aerobic conditions. OD600 of the culture was 2.714 after 48 h of incubation and cells were harvested by centrifugation and treated by 1 mmol?L?1 EDTA for 20 min. The cells were added into anolyteⅡ (PBBM liquid medium containing 2.000 g?L?1 sodium acetate as the substrate and 5.000 g?L?1 ferric citrate, pH 7.2) to prepare inoculation media with dry cell concentration of 3.394 g?L?1. After 14 d at room temperature, the power density of MFCs connecting to the external resistance 1000Ω reaches to 509 mW?m?2 , which is increased by 162.4% compared with the original. It is the first time thatT. osonensis is applied in MFCs and shows electrochemical activity.