金洪进,崔光勋

生物矿化是一种与各种微生物相关的众所周知的自然现象，研究员正在研究以保护和加固混凝土等建筑材料。我们对红球菌S26进行了表征，这是一种具有CaCO3形成活性的新型产脲酶细菌，并研究了其修复混凝土裂缝以开发环保型密封剂的能力。菌株S26在固体培养基中生长形成球形和多边形的CaCO3晶体。在含尿素液体培养基中生长的S26细胞导致培养液碱化并增加CaCO3水平，表明尿素分解是CaCO3形成的原因。脲酶活性和CaCO3形成随着孵育时间的增加而增加，在第四天分别达到最大值2054U/min/mL和3.83g/L。当使用乳酸钙作为钙源，然后使用葡萄糖酸钙时，CaCO3的形成达到最大。尽管在pH10.5的诱导期后观察到细胞生长，但菌株S26可以在pH4-10.5的宽范围内生长，显示出其高碱耐受性。FESEM显示尺寸为20–60µm的菱面体晶体。EDX分析表明晶体中存在钙、碳和氧。XRD证实这些晶体为含有方解石和球霰石的CaCO3。此外，R.erythreusS26成功修复了人工诱导的宽度为0.4-0.6mm的大裂缝。

碳酸钙；胶结材料；具体的；维修；尿素分解

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