碳酸盐矿化菌的分纯及其对Sr^(2+)的矿化特性研究

Isolation and Sr^(2+) Mineralization Mediated by Carbonate Mineralization Bacteria

土壤污染日益严重,其中作为土壤污染类型之一的放射性核素污染已引起广泛关注。土壤中的部分微生物可以矿化固结重金属离子,从而达到去除重金属离子的目的。本文实验对从土壤中分离的1株碳酸盐矿化菌的特性及其对Sr2+的矿化结果进行研究,发现该菌对1.0 g/L和0.5 g/L模拟核素Sr2+的去除率可达98%和99%。扫描电子显微镜(SEM)、能谱分析(EDS)、X射线衍射(XRD)、傅里叶变换红外光谱(FTIR)等结果显示,矿化产物为碳酸锶。可见,利用碳酸盐矿化菌治理土壤中放射性核素Sr2+污染具有可行性,该方法将会有一定应用前景。

Soil pollution has increasingly become a serious problem, especially by radionuclide pollution, and has attracted wide attention. Microbial remediation of radionuclide contaminated soil has been studied and proposed as a potential strategy. Because some microorganisms in soil can consolidate heavy metal to form mineralization, heavy metal inos can be removed from soil. A strain of carbonate mineralization bacterium was isolated from the soil and was used for the mineralization of Sr2+. The final removal rate of 1.0 g/L and 0.5 g/L Sr2 + was as high as 98% and 99%, respectively. Scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR) analyses revealed that the mineralized product was strontium carbonate. It is suggested that indigenous bacteria can survive soil radionuclide toxicity and strontium ions could be mineralized as stable carbonate minerals, which indicates important practicability for radionuclide or heavy metal bioremediation. Also, the finding will provide new insights into carbonate biomineralization.