Isolation and characterization of an electrochemically active and cyanide-degrading bacterium isolated from a microbial fuel cell

Abstract

A facultative anaerobic bacterium capable of generating electricity and degrading cyanide was isolated from a microbial fuel cell and was designated as MC-1. According to its morphological characteristics and the sequence analysis of 16S rDNA, the isolated bacterium was identified as a strain of Klebsiella sp. Cyclic voltammetry showed that the strain MC-1 exhibited high electrochemical activity. The preliminary electricity-production experiment showed that the strain MC-1 could use glucose–cyanide mixtures for electricity production in a microbial fuel cell (MFC). The maximum voltage was 412 mV, and the chemical oxygen demand (COD) removal rate and cyanide degradation rate were 88.34% and 99.51%, respectively, when the MFC was fed with glucose–cyanide mixtures. The results demonstrated that the strain MC-1 was promising for the bioremediation of cyanide-containing wastewater in MFCs.