Biomineralization is a common phenomenon in nature, and the use of microbial-induced calcium carbonate precipitation (MICP) technology for engineering construction is a successful attempt to utilize natural biological phenomena, which has become a hot topic of current research. There are many factors affecting MICP, such as bacterial properties and external environmental factors. Many scholars have carried out a lot of research on these factors, but even under appropriate conditions, the MICP process still has the problem of low efficiency. According to different engineering, the tolerance and effect of bacteria in different environments are also different. At the same time, the cultivation and preservation of bacteria will also consume a large amount of raw materials, which is far more significant than the cost of engineering construction. The efficiency and cost limit the large-scale application of this technology in practical engineering. In response to these problems, researchers are exploring new ways to improve the efficiency of MICP technology. Based on the bacteria used in MICP, this paper explores the mechanism of bacteria in the process of MICP and reviews the improvement of bacteria from the perspective of efficiency improvement and economy.

Microbially induced carbonate precipitation (MICP) is a promising biogeotechnical technology, but its large-scale application is constrained by the high cost and energy consumption of bacterial cultivation and harvesting. This paper presents a metal ion-induced flocculation strategy for the preparation and storage of high-density Sporosarcina pasteurii seed cultures. The flocculation performance and biological effects of Ca²⁺ and Fe³⁺ were systematically compared. Ca²⁺ achieved efficient flocculation through electrical double-layer compression while maintaining near-neutral pH, thereby preserving urease activity and bacterial viability. Even at an inoculation ratio of 1:10,000, the recovered bacteria exhibited rapid regrowth and high urease activity. In contrast, although Fe³⁺ induced rapid flocculation at low concentrations, the acidic conditions severely impaired bacterial viability and regrowth. Cryopreservation with glycerol at −20 °C maintained bacterial activity for at least 90 days and markedly outperformed storage at 4 °C. The recovered flocculated bacteria exhibited CaCO₃ precipitation performance comparable to that of freshly cultured suspensions. This study provides a simple, economical, and scalable strategy for the preparation and long-term storage of MICP seed cultures, facilitating the practical implementation of large-scale biogeotechnical applications.