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Updated: Jul 4, 2026
12:30
Development and Validation of Chromium Getters for Solid Oxide Fuel Cell Power Systems
Published on: May 26, 2019
Bacterial reduction of chromium.
E A Schmieman1, J N Petersen, D R Yonge
1Civil & Environmental Engineering Department, Washington State University, Pullman, WA, USA.
Applied Biochemistry and Biotechnology
|March 1, 1997
Summary
Chromate-contaminated soil harbors microbial cultures with varying chromium tolerance. Specific conditions, like Tryptic Soy Broth (TSB), enable chromate reduction, suggesting potential for in situ bioremediation strategies.
Area of Science:
- Environmental microbiology
- Bioremediation
- Soil science
Background:
- Chromate contamination in soil and groundwater poses environmental risks.
- Microbial communities play a crucial role in the fate of heavy metals in contaminated sites.
- Understanding microbial tolerance and reduction capabilities is key for developing effective remediation strategies.
Purpose of the Study:
- To enrich and characterize microbial cultures from chromate-contaminated soils.
- To assess the chromate tolerance and reduction potential of these microbial consortia under different conditions.
- To evaluate the impact of chromate concentration on microbial diversity.
Main Methods:
- Enrichment of mixed microbial cultures from chromate-contaminated surface and subsurface soils.
- Cultivation in minimal salts media with acetate and nitrate, supplemented with varying chromate levels.
- Testing chromate reduction capability in different media (minimal salts vs. Tryptic Soy Broth - TSB).
- Analysis of microbial diversity in relation to chromate concentration.
Main Results:
- Two distinct mixed cultures were enriched, one from the eastern US and another from the Hanford reservation.
- The eastern US culture showed growth inhibition at 12 mg/L chromium, while the Hanford culture tolerated this concentration.
- The Hanford culture demonstrated chromate reduction capability only when grown anaerobically on TSB, not on minimal salts medium.
- Microbial diversity decreased with increasing chromate levels in the enrichment medium.
Conclusions:
- Microbial communities from chromate-contaminated sites exhibit varying degrees of tolerance and specific metabolic capabilities for chromate reduction.
- The choice of growth medium significantly influences the observed chromate reduction potential of microbial consortia.
- These findings support the development of in situ bioremediation strategies for chromate-contaminated soil and groundwater, tailored to specific environmental conditions.
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