摘要
A strain of Klebsiella aerogenes(K.aerogenes)capable of decomposing calcium acetate for CaCO_(3) biomineralization was screened,and the optimum conditions for producing the maximum mass of CaCO_(3) crystals induced by Klebsiella aerogenes were found to be 0.25 mol/L calcium acetate,4%inoculum level,and pH 7.Following that,the monosaccharides and proteins contained in the extracellular polymeric substances(EPS)of Klebsiella aerogenes were identified.The effects of additional identified monosaccharide and proteins on the crystalline form conversion of CaCO_(3) crystals were investigated,and the additional monosaccharides were found to promote the crystalline form conversion of CaCO_(3) crystals from vaterite to calcite.Specifically,adding 1.00 g/L glucuronic acid was observed to enhance the conversion of crystalline phases of CaCO_(3) crystals to calcite completely after 5 d.Meanwhile,additional catalase was observed to contribute to the regular morphology of CaCO_(3) crystals without affecting their crystalline phases.The results indicate that the additional glucuronic acid influences the crystalline forms of CaCO_(3) crystals significantly.
筛选一株可以分解乙酸钙形成CaCO_(3)沉淀的菌株-产气克雷伯氏杆菌,确定其诱导产生CaCO_(3)沉淀产量的最适条件为0.25 mol/L乙酸钙、4%接种量及pH 7,随后,分析产气克雷伯氏杆菌胞外聚合物中的单糖和蛋白质成分,研究单糖和蛋白质对CaCO_(3)晶型转化的影响,发现添加单糖能促进CaCO_(3)晶相从球霰石向方解石转变。其中,添加1.00 g/L葡萄糖醛酸可促使CaCO_(3)晶体在5 d后完全转变为方解石。同时,添加过氧化氢酶能使CaCO_(3)晶体的形貌更加规则,但对晶相没有影响。结果表明,加入葡萄糖醛酸对CaCO_(3)晶体的晶型有显著影响。
基金
supported by the National Natural Science Foundation of China(Nos.U20A20267,U1967210,12275123)
Hunan Provincial Science Fund for Distinguished Young Scholars,China(No.2022JJ10041)
the Program of Science and Technology Department of Hunan Province,China(Nos.2020 TJ-Q03,2022SK2077).
