Department of Life Sciences, Bhakta Kavi Narsinh Mehta University, Khadiya, Junagadh, 362263, India.
Department of Biosciences, Veer Narmad South Gujarat University, Udhana - Magdalla Road, Surat, Gujarat, India.
Sci Rep. 2024 Oct 14;14(1):23976. doi: 10.1038/s41598-024-75019-7.
Microbially Induced Calcite Precipitation (MICP) has emerged as a promising technique for bio-cementation, soil improvement, and heavy metal remediation. This study explores the potential of Bhargavaea beijingensis, a urease-producing bacterium, for these applications. Six ureolytic bacteria were isolated from calcareous bricks mine soil and screened for urease and calcite production. B. beijingensis exhibited the highest urease activity and calcite precipitation. Urease activity, calcite precipitation, sand solidification, heavy metal removal efficiency, and compressive strength were evaluated. It showed significant heavy metal removal efficiency, particularly highest for HgCl. Mortar blocks treated with B. beijingensis or its crude enzyme exhibited improved compressive strength, suggesting its potential for bio-cementation. Crack remediation tests demonstrated successful crack healing in mortar blocks using the bacterium or its enzyme. This study identifies B. beijingensis as a novel and promising MICP agent with potential applications in bio-cementation, soil improvement, and heavy metal remediation. Hence, B. beijingensis diversified abilities prove superior performance compared to commonly used strains like Bacillus subtilis and Shewanella putrefaciens in bio-cementation applications. Its high urease activity, calcite precipitation, and heavy metal removal abilities make it a valuable candidate for sustainable and eco-friendly solutions in various fields.
微生物诱导碳酸钙沉淀(MICP)技术已成为生物胶结、土壤改良和重金属修复的一种很有前途的方法。本研究探讨了产脲酶细菌 Bhargavaea beijingensis 在这些应用中的潜力。从钙质砖矿土壤中分离出六种脲酶产生菌,并对其脲酶和碳酸钙产生能力进行了筛选。B. beijingensis 表现出最高的脲酶活性和碳酸钙沉淀能力。评估了脲酶活性、碳酸钙沉淀、砂土固化、重金属去除效率和抗压强度。结果表明,该菌对重金属具有很高的去除效率,特别是对 HgCl2 的去除效率最高。用 B. beijingensis 或其粗酶处理的砂浆块表现出抗压强度的提高,表明其在生物胶结方面的潜力。裂缝修复试验表明,该菌或其酶可成功修复砂浆块中的裂缝。本研究确定 B. beijingensis 是一种新型的、有前途的 MICP 剂,具有在生物胶结、土壤改良和重金属修复方面的应用潜力。因此,与枯草芽孢杆菌和腐败希瓦氏菌等常用菌株相比,B. beijingensis 在生物胶结应用中的多样化能力表现出更优异的性能。其高脲酶活性、碳酸钙沉淀和重金属去除能力使其成为各个领域可持续和环保解决方案的有价值的候选者。