Lysinibacillus Sp. And Arthrobacter Sp. Induced Carbonate Minerals

Microbial induced carbonate mineral process has great significance because it is beneficial to use mineral capture technology to fix atmospheric CO2 and is likely to provide important clues in discovering extraterrestrial life and so on. At present, many research results of microbial carbonate minerals are available, but still numerous key issues are unclear. For example, location of mineral nucleation sites, factors controlling the formation of minerals, factors controlling the polymorphism of calcium carbonate mineral and so on. In order to explore the relationship between microbial morphology and forms of carbonate minerals, in this paper Lysinibacillus sp. strain and Arthrobacter sp. strain were used to conducted a series of experiments. We uesd X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FT-IR), Scanning Electron Microscope (SEM), and Energy Dspersive Spectrometer (EDS) to analysis species and morphologies of minerals. High Performance Liquid Chromatography (HPLC) and Inductively Coupled Plasma Optical Emission Spectrometer (ICP-OES) were used to study on the factors affecting the formation of carbonate minerals.The main results are as follows:(1) Lysinibacillus sp. strain GW-2 and Arthrobacter sp. strain MF-2 both have the ability to induce the formation of carbonate minerals. The former induced the formation of both vaterite and calcite, but the latter induced the formation of only vaterite.(2) Rod-shaped bacteria induced the formation dumbbell-shaped, spherical, rod and tetragonal pyramid shaped minerals.But spherical bacteria induced the formation bowl and spherical minerals. This shows that there is a link of bacterial morphology and the types of minerals. Holes were observed in the surface of some spherical minerals. When the sediment was treated H2O2, the number of holes increased. Moreover the diameter of the hole is similar to the diameter of the bacteria. We speculated that was the trace which the bacteria oxidized.(3) Vaterite that were compounded with chemical method in deionized water for 10 d, transformed into calcite. But vaterite that were soaked under the presence of bacteria remained unchanged. In air and under UV radiation, the vaterite that were compounded with both the methods remained unchanged.(4) Strain MF-2 induced the formation of spherical vaterite in M2 medium without Mg2+, whereas, tetragonal pyramid shaped high Mg calcite appeared in the M2 medium containing Mg2+. This showed that Mg2+ has some influence on the mineral species and morphology.(5) Under quite culture, strain GW-2 induced the formation of calcite, but under shaking culture, strain GW-2 induced the formation of vaterite.