Microbially Induced Carbonate Precipitation (MICP): New strains, new perspectives

The process of microbially induced carbonate precipitation (MICP) is revolutionizing construction and geotechnical engineering. By harnessing the ability of microorganisms to induce calcium carbonate formation, it is possible to sustainably and environmentally produce construction materials and other substances of interest. Ureolytic bacteria, such as Bacillus pasteurii, play a key role in biocementation. Few studies have identified new bacteria capable of performing MICP. This work aims to select urease-producing strains from water and soil samples collected from extreme Algerian ecosystems. A total of 34 different bacterial strains were isolated at 47°C. A thermophilic test confirmed the growth of 11 strains at 55°C. Screening on UNB medium was conducted to select urease-producing bacteria. After a 3-day incubation, calcite crystals formed in the UNB medium, confirmed by microscopy. An application test was conducted to select microbial strains based on their ability to solidify construction sand through biocementation. The bacteria isolated and screened from this work promise to significantly advance MICP research.