Construction of alginate beads for efficient conversion of CO2 into vaterite CaCO3 particles

Abstract

CO 2 is a greenhouse gas and a major contributor to global warming. Efficient conversion of CO 2 into high value-added food materials represents a promising strategy to decrease CO 2 concentration. In this study, we reported that Ca 2+ -crosslinked alginate beads loaded with carbonic anhydrase (CA) can efficiently catalyze conversion of CO 2 into porous vaterite CaCO 3 particles via a carboxymethyl cellulose (CMC) inducing process. CA encapsulated within the Ca 2+ -crosslinked alginate beads maintained around 100% activity of its original activity after 10 assay cycles. Functionally, the CA-loaded alginate beads facilitated conversion of CO 2 into porous vaterite CaCO 3 particles with high CO 2 removal efficiency in the presence of carboxymethyl cellulose. Notably, such vaterite CaCO 3 particles can be explored for adsorption of astaxanthin with higher loading capacity (2.0 wt %), consequently improving the photo- and thermal-stability of this pigment. • Carbonic anhydrase loaded within alginate beads serves as an edible CO 2 absorber. • These synthesized alginate beads convert CO 2 into vaterite CaCO 3 particles via CMC. • The obtained porous vaterite CaCO 3 particles have high astaxanthin loading capacity. • The vaterite CaCO 3 particles greatly improve the photothermal stability of astaxanthin.