Inhibitory effect of nitrate on Fe(III) and humic acid reduction in Shewanella putrefaciens DK-1

Abstract

The inhibitory effects of nitrate on Fe(III) and humic acid reduction were examined in Shewanella putrefaciens DK-1. There is no difference in Fe(III) reduction until 25 hours between cultures using Fe(III) alone as an electron acceptor and using Fe(III) and nitrate as electron accepters, hut after 25 hours Fe(II) production was decreased drastically when Fe(II) and nitrate were used as electron accepters. The production of AHQDS (2,6-anthrahydroquinon disulfonate) showed similar patterns when AQDS alone and both AQDS and Fe(III) were used as electron accepters. When AQDS (2,6-anthraquinon disulfonate) and nitrate were used as electron accepors, the production of AHQDS was completely inhibited.