Influence of Native Ureolytic Microbial Community on Biocementation Potential of Sporosarcina Pasteurii

Microbially induced calcium carbonate precipitation (MICP)/Biocementation has emerged as a promising technique for soil engineering applications. There are chiefly two methods by which MICP is applied for field applications including biostimulation and bioaugmentation. Although bioaugmentation strategy using efficient ureolytic biocementing culture of Sporosarcina pasteurii is widely practiced, the impact of native ureolytic microbial communities (NUMC) on CaCO 3 mineralisation via S. pasteurii has not been explored. In this paper, we investigated the effect of different concentrations of NUMC on MICP kinetics and biomineral properties in the presence and absence of S. pasteurii. Kinetic analysis showed that the biocementation potential of S. pasteurii is 6-fold higher than the NUMC and is not significantly impacted even when the concentration of the NUMC is eight times higher. Micrographic results revealed a quick rate of CaCO 3 precipitation by S. pasteurii led to the generation of smaller CaCO 3 crystals (5–40 µm), while the slow rate of CaCO 3 precipitation by NUMC led to the creation of larger CaCO 3 crystals (35–100 µm). Mineralogical results showed the predominance of the calcite phase in both sets. The outcome of the current study is crucial for tailor-made applications of MICP.