摘要：The biogeochemical cycle of iron has special environmental effects, and iron-reducing bacteria plays a very important role in this iron cycling process. In this paper, we studied the electron shuttle effect of nine natural and synthetic organic electron mediators, including quinones, humic acid and fulvic acid with low molecular weight numbers, on the bioreduction of goethite (α-FeOOH) with three iron-reducing bacteria Klebsiella pneumoniae (L17), Aeromonas hydrophila (S12) and Shewanel- la decolorationis (HS01). We found that all the iron-reducing bacteria could reduce goethite without the addition of these exogenous electron mediators, which, however, could accelerate the bioreduction of goethite when present. We also reveal that the electron shuttling effect of electron mediators is affected by its redox potential and the degree of shuttling is linear to its electron acceptor capacity (EAC).
关键词：Electron shuttle;iron-reducing bacteria;electron acceptor capacity;ferrous iron
