State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, No 73 Huanghe Road, Nangang District, Harbin 150090, China.
Key Laboratory of Coastal Biology and Biological Resources Utilization, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, No 17 Chunhui Road, Laishan District, Yantai 264003, Shandong, China.
Water Res. 2018 Oct 1;142:441-451. doi: 10.1016/j.watres.2018.05.058. Epub 2018 Jun 5.
Biochar has been reported to facilitate direct interspecies electron transfer (DIET) in co-cultures between Geobacter metallireducens and Geobacter sulfurreducens, a model defined co-culture system. In this study, the biochar derived from the activated sludge with different pyrolysis temperature was added to the co-cultures, the ethanol metabolism rates (Re) and succinate production rates (Rs) of co-culture with biochar-800 were 1.05- and 1.42-fold higher than that without addition. The results suggested that the conductivity of the biochar did not correlate with the facilitating effect of the biochar on the co-culture metabolism. Furthermore, the surface functional group and surface charge of biochar may also influence the facilitating effect on the interspecies electron transfer between the two Geobacter cells. Based on these results, it supported that the electron transfer depending on the charging and discharging process of the surface functional groups might play a major role in facilitating the direct electron transfer process by the biochar derived from activated sludge here. This study could shed light on the better understanding of the bacteria-biochar electron transfer system and the potential utilization of the biochar in the environmental wastewater treatments.
生物炭已被报道可促进 Geobacter metallireducens 和 Geobacter sulfurreducens 共培养物中的直接种间电子转移 (DIET)，这是一个定义明确的共培养系统。在这项研究中，将不同热解温度下从活性污泥中得到的生物炭添加到共培养物中，添加生物炭-800 的共培养物的乙醇代谢速率 (Re) 和琥珀酸产生速率 (Rs) 分别比未添加时高 1.05 倍和 1.42 倍。结果表明，生物炭的电导率与生物炭对共培养物代谢的促进作用无关。此外，生物炭的表面官能团和表面电荷也可能影响生物炭对两种 Geobacter 细胞之间种间电子转移的促进作用。基于这些结果，支持了基于表面官能团的充放电过程的电子转移可能在通过活性污泥衍生的生物炭促进直接电子转移过程中起主要作用。本研究可以更好地了解细菌-生物炭电子转移系统，并为生物炭在环境废水处理中的潜在利用提供依据。
