Optimization of Indigenous Alkalophilic Bacteria of Sambhar Lake on B4 Medium

This study explores the isolation and characterization of alkalophilic bacterial strains from the hypersaline Sambhar Lake, with a focus on their potential for mineral precipitation, specifically calcium carbonate. Soil samples were collected from the lake and analyzed for physicochemical properties, revealing an alkaline pH (9) and high salinity, conditions conducive to the growth of halophilic bacteria. Bacteria were grown on 10% NaCl nutrient agar and subsequently cultured on specialized B4 medium for mineral precipitation. Five distinct bacterial strains were isolated, identified through 16S rRNA sequencing as Halomonas salifodinae UJSL1, Oceanobacillus kimchii UJSL2, Halobacillus dabanensis UJSL3, Halomonas mongoliensis UJSL4 and Halomonas campaniensis UJSL5. All strains demonstrated urease activity and produced significant calcium carbonate precipitates. Halomonas salifodinae UJSL1 and Halomonas mongoliensis UJSL4 were the most effective in producing large, well-formed crystals as confirmed by SEM analysis. The findings suggest that these strains hold potential for applications in biocementation, carbon sequestration and environmental remediation. The study contributes valuable insights into the use of halophilic bacteria for sustainable and eco-friendly biomineralization processes.