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Development and Validation of Chromium Getters for Solid Oxide Fuel Cell Power Systems
Published on: May 26, 2019
Chromate reduction by chromium-resistant bacteria isolated from soils contaminated with dichromate
F A O Camargo1, F M Bento, B C Okeke
1Department of Environmental Science, Univ. of California, Riverside, CA 92521, USA.
Journal of Environmental Quality
|August 23, 2003
Summary
Chromium-resistant bacteria, primarily Bacillus species, effectively reduce toxic hexavalent chromium [Cr(VI)] in contaminated soils. These microbes show optimal reduction at pH 7.0-9.0 and 30°C, offering a promising bioremediation strategy.
Area of Science:
- Environmental Microbiology
- Bioremediation
- Toxicology
Background:
- Hexavalent chromium [Cr(VI)] is a toxic industrial pollutant causing significant environmental contamination.
- Chromium-resistant bacteria offer a sustainable biological solution for removing Cr(VI) from contaminated ecosystems.
Purpose of the Study:
- To isolate and characterize chromium-resistant bacteria from contaminated soils.
- To investigate the influence of environmental factors (pH, temperature, time) on Cr(VI) resistance and reduction.
- To evaluate the Cr(VI) reduction potential of isolated bacterial strains.
Main Methods:
- Isolation of Cr(VI)-resistant bacteria from dichromate-contaminated soils.
- Identification of bacterial isolates using 16S rRNA gene sequencing.
- Assay of Cr(VI) reduction activity under varying pH, temperature, and time conditions.
- Determination of kinetic parameters (K(M), V(max)) for Cr(VI) reduction.
Main Results:
- Isolated bacteria exhibited tolerance to Cr(VI) up to 2500 mg L(-1), with significant reduction observed below 1500 mg L(-1).
- Five isolates demonstrated chromate reduction activity, predominantly belonging to the genus Bacillus.
- Optimal Cr(VI) reduction occurred at pH 7.0-9.0 and 30°C.
- Bacillus sp. ES 29 achieved 90% aerobic Cr(VI) reduction within six hours, with specific kinetic parameters identified.
Conclusions:
- The identified Bacillus isolates possess significant Cr(VI) reduction capabilities.
- These bacteria are effective under a range of environmental conditions, making them suitable for bioremediation.
- Bacterial consortia and monocultures can be employed for Cr(VI) detoxification in contaminated environments.
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