Achieving a carbon-neutral, decarbonized society is being strongly demanded not only in Japan but also worldwide. Decarbonization is a challenge closely related to the global environment and ecosystems, and thus requires university-wide initiatives in both research and education at the University of Tokyo, with particular emphasis on agricultural approaches that include marine studies.

Various methods of decarbonization are being explored. Among them, CCS (Carbon dioxide Capture and Storage), which stores carbon dioxide underground as a direct means of fixing atmospheric CO₂, has been the most advanced in research and development. Efforts that utilize photosynthesis in plants to fix carbon dioxide into organic matter are also actively being pursued. However, despite the fact that the most abundant chemical form of carbon on Earth is calcium carbonate (40,000 million gigatons), very little effort has been made to fix carbon dioxide in the form of calcium carbonate. The main reason is that, due to the protons generated during the calcification of calcium carbonate, biomineralization has been regarded as a reaction that releases carbon dioxide from the ocean, and therefore as not contributing to carbon fixation.

This view was established prior to the 1990s, and discussions were carried out under the assumption that biologically induced calcification is essentially the same as the inorganic formation of calcium carbonate from seawater. However, recent advances in biomineralization research have revealed that biological reactions involve a sharp increase in pH prior to calcification, that specialized biomineral proteins act as catalysts to kinetically promote the binding of calcium and carbonate ions, and that the crystalline form, orientation, and defects of calcium carbonate are strictly controlled. These findings indicate that proton release during biomineralization does not directly lead to the release of CO₂ from the ocean, and that if the released protons can be properly managed, it is possible to fix carbon using calcium sources from seawater. Because the conversion of carbon dioxide into calcium carbonate requires no external energy input, the cost of fixation is low, the product is stable in solid form with no risk of leakage, and furthermore, the synthesized calcium carbonate can be utilized industrially (CCUS: Carbon dioxide Capture, Utilization and Storage), making it possible to generate profit through its sale.

Nevertheless, because the paradigm that biomineralization does not contribute to carbon fixation became entrenched prior to the 1990s, such new attempts are difficult for many researchers to accept. By strengthening activities centered on the Biomineralization Research Society as a hub for decarbonization research and education, we aim to disseminate new scientific perspectives to society and to develop innovative CCUS technologies.