Williams Sarah L, Kirisits Mary Jo, Ferron Raissa Douglas
Department of Civil, Architectural, and Environmental Engineering, University of Texas at Austin, 301 East Dean Keeton Street, Stop C1700, Austin, TX, 78712, USA.
J Ind Microbiol Biotechnol. 2016 Apr;43(4):567-75. doi: 10.1007/s10295-015-1726-2. Epub 2016 Jan 21.
Microbial-induced calcium carbonate precipitation has been identified as a novel method to improve durability and remediate cracks in concrete. One way to introduce microorganisms to concrete is by replacing the mixing water with a bacterial culture in nutrient medium. In the literature, yeast extract often has been used as a carbon source for this application; however, severe retardation of hydration kinetics has been observed when yeast extract is added to cement. This study investigates the suitability of alternative carbon sources to replace yeast extract for microbial-induced calcium carbonate precipitation in cement-based materials. A combination of meat extract and sodium acetate was identified as a suitable replacement in growth medium for Sporosarcina pasteurii; this alternative growth medium reduced retardation by 75 % (as compared to yeast extract) without compromising bacterial growth, urea hydrolysis, cell zeta potential, and ability to promote calcium carbonate formation.
微生物诱导碳酸钙沉淀已被确认为一种提高混凝土耐久性和修复裂缝的新方法。将微生物引入混凝土的一种方法是用营养培养基中的细菌培养物替代拌合水。在文献中，酵母提取物经常被用作此应用的碳源；然而，当将酵母提取物添加到水泥中时，已观察到水化动力学严重迟缓。本研究调查了替代碳源在水泥基材料中替代酵母提取物用于微生物诱导碳酸钙沉淀的适用性。已确定肉提取物和醋酸钠的组合是巴氏芽孢八叠球菌生长培养基中的合适替代品；这种替代生长培养基将迟缓降低了75%（与酵母提取物相比），同时不影响细菌生长、尿素水解、细胞zeta电位以及促进碳酸钙形成的能力。
