Enhanced biomimetic sequestration of CO2 into CaCO3 using purified carbonic anhydrase from indigenous bacterial strains

A review of microbial precipitation for sustainable construction

“…Microbially induced carbonate precipitation via carbonic anhydrase has offered the possibility of capturing CO 2 into safe, stable and environmentally benign carbonate reservoirs and a permanent method for disposing off CO 2 [93,94]. Bacterial carbonic anhydrase from Bacillus megaterium has recently been found to act synergistically with the urease in biomineralisation of calcium carbonates [39].…”

“…Bacterial carbonic anhydrase from Bacillus megaterium has recently been found to act synergistically with the urease in biomineralisation of calcium carbonates [39]. The potential of this enzyme in accelerating the precipitation of Ca-carbonate minerals (such as calcite) from Ca-rich solutions is being utilised through chemical buffers and pure CO 2 gas [21,44,45,65,69,94,105]. After MICP via bacterial cells, several studies have now reported cyanobacteria as efficient point-sources for carbon capture and sequestration by utilising solar energy to carryout photosynthesis that converts CO 2 into recalcitrant calcium carbonate minerals [57,62].…”

Strategizing Carbon-Neutral Mines: A Case for Pilot Projects

“…An alternative means of increasing CO 2 supply involves the direct use of CA, which catalyzes the hydration of aqueous CO 2 , for carbon mineralization. CA is produced by prokaryotes and eukaryotes and is actively being investigated as an additive for accelerating carbonate precipitation, typically as part of an industrial process [39,[127][128][129][130][131]. A challenge associated with elevated CO 2 concentrations is that dissolving CO 2 into water decreases pH, and therefore decreases carbonate mineral saturation.…”

Carbon sequestration via carbonic anhydrase facilitated magnesium carbonate precipitation

“…CA is functional in the presence of Ca 2+ , Mg 2+ , Na + , and K + ions; however, the activity of CA varies depending on pH, temperature, and salinity, and decreases with time (Sharma and Bhattacharya, 2010;Wilbur and Anderson, 1948). The optimum conditions for BCA activity are at pH 7, 35 • C, and low salt concentration (e.g., 0.005 M Mg 2+ ) (Sharma and Bhattacharya, 2010), yet a more alkaline pH and greater salt concentration are more favourable for carbonate precipitation. The activity of BCA as a function of pH has been reported to be 39%, 36%, and 33% at pH values of 8.5, 9.0, and 9.5, respectively after 6 h of incubation (Sharma and Bhattacharya, 2010).…”

“…For instance, several studies have examined the effect of carbonic anhydrase (CA), an enzyme that catalyzes the hydration of aqueous CO 2 , in accelerating the precipitation of Ca-carbonate minerals (e.g., calcite; CaCO 3 ) from Ca-rich solutions using chemical buffers and pure CO 2 gas (Bond et al, 2001;Dilmore et al, 2009;Favre et al, 2009;Lee et al, 2010;Mirjafari et al, 2007;Sharma and Bhattacharya, 2010;Vinoba et al, 2011a). Yet, if efficient processes can be developed, capture of CO 2 directly from the atmosphere has significant potential for sequestering CO 2 without the need for concentrated point sources (Lackner, 2009).…”