Reduction of bromate to bromide coupled to acetate oxidation by anaerobic mixed microbial cultures.
Bromate, a weakly mutagenic oxidizing agent, exists in surface waters. The biodegradation of bromate was investigated by assessing the ability of mixed cultures of micro-organisms for utilization of bromate as electron acceptor and acetate as electron donor. Reduction of bromate was only observed at relatively low concentrations (<3.0 mM) in the absence of molecular oxygen. Under these conditions bromate was reduced stoichiometrically to bromide. Unadapted sludge from an activated sludge treatment plant and a digester reduced bromate without lag period at a constant rate. Using an enrichment culture adapted to bromate, it was demonstrated that bromate was a terminal electron acceptor for anaerobic growth. Approximately 50% of the acetate was utilized for growth with bromate by the enrichment culture. A doubling of 20 h was estimated from a logarithmic growth curve. Other electron acceptors, like perchlorate, chlorate and nitrate, were not reduced or at negligible rates by bromate-utilizing microorganisms.
van Ginkel
C G
CG
Akzo Nobel Chemicals, P.O. Box 9300, 6800 SB Arnhem, The Netherlands. kees.vanginkel@akzonobel.com
van Haperen
A M
AM
van der Togt
B
B
D000085:Acetates / Q000737:chemistry / Q000378:metabolism; D001421:Bacteria, Anaerobic / Q000254:growth & development / Q000378:metabolism*; D001673:Biodegradation, Environmental; D001959:Bromates / Q000032:analysis / Q000378:metabolism*; D001965:Bromides / Q000032:analysis / Q000378:metabolism; D010084:Oxidation-Reduction; D012722:Sewage / Q000382:microbiology*; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000378:metabolism*
D000085:Acetates; D001959:Bromates; D001965:Bromides; D012722:Sewage; D014874:Water Pollutants, Chemical