Jiangsu Key Laboratory of Construction Materials, Southeast University, Nanjing 211189, China.
Institute of Geotechnical Engineering, Southeast University, Nanjing, Jiangsu 211189, China.
Ecotoxicol Environ Saf. 2023 Sep 15;263:115305. doi: 10.1016/j.ecoenv.2023.115305. Epub 2023 Jul 28.
Heavy metals are pervasive pollutants found in water, soil, and solid wastes. Bio-solidification offers an environmentally friendly approach to immobilize heavy metal ions using two types of bacteria: urease-producing bacteria (UPB) and phosphatase-producing bacteria (PPB). UPB, exemplified by Sporosarcina pasteurii, secretes urease to hydrolyze urea and generate CO ions, while PPB, like Bacillus subtilis, produces alkaline phosphatase to hydrolyze organophosphate monoester (ROP) and produce PO ions. These ions react with heavy metal ions, effectively reducing their concentration by forming insoluble carbonate or phosphate precipitates. The success of bio-solidification is influenced by various factors, including substrate concentration, temperature, pH, and bacterial density. Optimal operational conditions can significantly enhance the remediation performance of heavy metals. UPB and PPB hold great potential for remediating heavy metal pollution in diverse contaminated areas such as tailings ponds, electroplating sewage, and garbage incineration plants. In conclusion, harnessing the power of these microbial methods can provide effective solutions for remediating heavy metal-induced pollution across a range of environmental conditions.
重金属是广泛存在于水、土壤和固体废弃物中的污染物。生物固化提供了一种环保的方法，利用两种类型的细菌（产脲酶细菌和产磷酸酶细菌）来固定重金属离子。产脲酶细菌（如巴斯德氏芽孢杆菌）分泌脲酶将尿素水解生成 CO32-离子，而产磷酸酶细菌（如枯草芽孢杆菌）则产生碱性磷酸酶将有机磷酸单酯（ROP）水解生成 PO43-离子。这些离子与重金属离子反应，通过形成不溶性碳酸盐或磷酸盐沉淀，有效地降低了重金属离子的浓度。生物固化的成功受到多种因素的影响，包括基质浓度、温度、pH 值和细菌密度。最佳操作条件可以显著提高重金属的修复性能。产脲酶细菌和产磷酸酶细菌在尾矿池、电镀污水和垃圾焚烧厂等多种污染区域中具有很大的潜力，可以用来修复重金属污染。总之，利用这些微生物方法可以为在各种环境条件下修复重金属污染提供有效的解决方案。
