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Updated: Jan 5, 2026
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Microbiologically Induced Calcite Precipitation Mediated by Sporosarcina pasteurii
Published on: April 16, 2016
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Complementing urea hydrolysis and nitrate reduction for improved microbially induced calcium carbonate precipitation
Xuejiao Zhu1,2, Jianyun Wang3, Nele De Belie1
1Magnel Laboratory for Concrete Research, Department of Structural Engineering, Faculty of Engineering and Architecture, Ghent University, Tech Lane Ghent Science Park, Campus A, Technologiepark Zwijnaarde 60, 9052, Ghent, Belgium.
Applied Microbiology and Biotechnology
|October 23, 2019
Summary
This study enhanced calcium carbonate (CaCO3) precipitation in self-healing concrete by combining urea hydrolysis and nitrate reduction in Ralstonia eutropha H16. This approach improved bacterial CaCO3 yield by 20-30%.
Area of Science:
- Materials Science
- Microbiology
- Civil Engineering
Background:
- Bacterial-induced calcium carbonate (CaCO3) precipitation is key for self-healing concrete.
- Limited CaCO3 production by bacteria in concrete matrices hinders this technology.
Purpose of the Study:
- To investigate combining urea hydrolysis and nitrate reduction in a single bacterial strain to boost CaCO3 yield.
- To identify a suitable bacterial strain for enhanced CaCO3 precipitation.
Main Methods:
- Screened three bacterial strains for Ca2+ tolerance and dual metabolic pathway capability.
- Selected Ralstonia eutropha H16 for its high Ca2+ tolerance and ability to perform both urea hydrolysis and nitrate reduction.
- Optimized conditions using orthogonal experiments.
Main Results:
- Ralstonia eutropha H16 efficiently performs urea hydrolysis independently of oxygen.
- Urea addition slowed nitrate reduction, and high Ca2+ concentrations inhibited nitrate reduction.
- The combined metabolic pathways improved overall CaCO3 precipitation yield by 20-30%, reaching 14 g/L.
Conclusions:
- Ralstonia eutropha H16 is a promising bacterium for simultaneous urea hydrolysis and nitrate reduction.
- This dual-pathway approach significantly enhances CaCO3 precipitation for self-healing concrete.
- Future research should explore activating multiple metabolic pathways in bacteria for concrete applications.
Keywords:
CaCO3 precipitationNitrate reductionRalstonia eutropha H16Self-healing concreteUrea hydrolysisMore Related Videos
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