Reject water, which is the liquid fraction produced after dewatering of anaerobically digested activated sludge on the municipal wastewater treatment plants (MWWTPs), contributes up to 80% of the nitrogen and phosphorus loads to the MWWTP. It was proposed to combine the removal of nitrogen from reject water using the sequential biooxidation of NH(4)(+) and bioreduction of NO(3)(-) with precipit...

Mitomycin C (MMC), a bifunctional alkylating agent, requires metabolic reduction to become biologically active. We have identified a series of genetically related Chinese hamster ovary cell lines which span approximately three orders of magnitude in the concentration of MMC required for cell killing. Many mechanisms, including drug transport, drug activation, drug detoxification, and the elimin...

Bioreduction of ferric iron-rich wastes is a rapidly emerging technology for the extraction/ recovery of metals from low-grade ores and metallurgical wastes. However, despite studies being successful, they have only been demonstrated at laboratory scale and issues relating to economic, industrial scale application have yet to be studied. Using bioreduction as a pre-treatment to increase recover...

It has been demonstrated in laboratory systems that U(VI) can be reduced to immobile U(IV) by bacteria in natural environments. The ultimate efficacy of bioreduction at the field scale, however, is often challenging to quantify and depends on site characteristics. In this work, uranium bioreduction rates at the field scale are quantified, for the first time, using an integrated approach. The ap...

The effect of zinc on the biological reduction of hematite (alpha-Fe2O3) by the dissimilatory metal-reducing bacterium (DMRB) Shewanella putrefaciens CN32 was studied in the presence of four natural organic materials (NOMs). Experiments were performed under non-growth conditions with H2 as the electron donor and zinc inhibition was quantified as the decrease in the 5 d extent of hematite biored...

Chromium (VI) (Cr(VI)) contamination of soil and groundwater is considered a major environmental concern. Bioreduction of Cr(VI) to chromium (III) (Cr(III)) can be considered an effective technology in remediating Cr(VI) contaminated sites. Among the Cr(VI) reducing bacteria, Shewanella oneidensis MR-1 (MR-1) is relatively effective. Reduction of Cr(VI) by MR-1 is defined by the dual-enzyme kin...

This study investigated bioreduction of selenite by anaerobic granular sludge in the presence of heavy metals and analyzed the fate of the bioreduced selenium and the heavy metals. Selenite bioreduction was not significantly inhibited in the presence of Pb(II) and Zn(II). More than 92% of 79 mg/L selenite was removed by bioreduction even in the presence of 150 mg/L of Pb(II) or 400mg/L of Zn(II...

This paper presents and validates a new paradigm for modeling complex biogeochemical systems using a diagonalized reaction-based approach. The bioreduction kinetics of hematite ( -Fe2O3) by the dissimilatory metal-reducing bacterium (DMRB) Shewanella putrefaciens strain CN32 in the presence of the soluble electron shuttling compound anthraquinone-2,6-disulfonate (AQDS) is used for presentation/...

As one of the transition metals, vanadium (V) (V(V)) in trace amounts represents an essential element for normal cell growth, but becomes toxic when its concentration is above 1mg/L. V(V) can alter cellular differentiation, gene expression, and other biochemical and metabolic phenomena. A feasible method to detoxify V(V) is to reduce it to V(IV), which precipitates and can be readily removed fr...