Selection and community analysis of halophilic mixed exoelectrogens from salt lake soils

Abstract

In this study, two slightly different halophilic mixed exoelectrogens were enriched and selected from salt lake soils. The results showed that the selected mixed exoelectrogens ESA from the sample OSA (Xiaochaidan Lake soil) and ESB from the sample OSB (Dachaidan Lake soil), without additional NaCl, produced current densities of 1231.1 and 1050.2 μA cm⁻², which were 89.6% and 61.7% higher than the typical exoelectrogen G. sulfurreducens PCA, respectively. ESA and ESB could produce 2.7 and 1.9 times higher currents than that obtained using G. sulfurreducens PCA with an additional 1.5% NaCl, respectively. The community diversity data demonstrated that Proteobacteria was the most abundant phylum, in which Enterobacteriaceae and Rhodocyclaceae were the dominant families for both ESA and ESB. Furthermore, at the genus level, the dominant genera Propionivibrio and Escherichia-Shigella were also shared by both. ESA had higher species diversity compared to ESB.