School of Minerals Processing and Bioengineering, Key Laboratory of Biohydrometallurgy of Ministry of Education, Central South University, Changsha 410083, China.
School of Minerals Processing and Bioengineering, Key Laboratory of Biohydrometallurgy of Ministry of Education, Central South University, Changsha 410083, China.
Sci Total Environ. 2022 Dec 1;850:157995. doi: 10.1016/j.scitotenv.2022.157995. Epub 2022 Aug 12.
Microbial induced phosphate precipitation (MIPP) is an advanced bioremediation technology to reduce the mobility and bioavailability of heavy metals (HMs), but the high level of HMs would inhibit the growth of phosphate solubilizing microbes. This study proposed a new combination system for the remediation of multiple HMs contaminated acidic mine soil, which included hydroxyapatite (HAP) and Phanerochaete chrysosporium (P. chrysosporium, PC) that had high phosphate solubilizing ability and HMs tolerance. Experimental data suggested that in HAP/PC treatment after 35 d of remediation, labile Cr, Zn and As could be transformed into the stable fraction with the maximum immobilization efficiencies increased by 53.01 %, 22.43 %, and 35.65 %, respectively. The secretion of organic acids by P. chrysosporium was proved to promote the dissolution of HAP. Besides, the pH value, available phosphorus (AP) and organic matter (OM) increased in treated soil than in original soil, which also indicated the related dissolution-precipitation mechanism of HMs immobilization. Additionally, characterization results revealed that adsorption and ion exchange also played an important role in the remediation process. The overall results suggested that applying P. chrysosporium coupled with HAP could be considered as an efficient strategy for the remediation of multiple HMs contaminated mine soil and laid a foundation for the future exploration of soil microenvironment response during the remediation process.
微生物诱导磷酸盐沉淀（MIPP）是一种先进的生物修复技术，可降低重金属（HM）的迁移性和生物可利用性，但高水平的 HM 会抑制磷酸盐溶解微生物的生长。本研究提出了一种新的组合系统，用于修复多种 HM 污染的酸性矿山土壤，其中包括具有高磷酸盐溶解能力和 HM 耐受性的羟基磷灰石（HAP）和黄孢原毛平革菌（P. chrysosporium，PC）。实验数据表明，在修复 35 d 后的 HAP/PC 处理中，可利用的 Cr、Zn 和 As 可转化为稳定的部分，最大固定效率分别提高了 53.01%、22.43%和 35.65%。证明黄孢原毛平革菌分泌的有机酸促进了 HAP 的溶解。此外，处理土壤的 pH 值、有效磷（AP）和有机质（OM）均高于原始土壤，这也表明了 HM 固定的相关溶解-沉淀机制。此外，特征化结果表明，吸附和离子交换在修复过程中也起着重要作用。总体结果表明，应用黄孢原毛平革菌与 HAP 相结合可以被认为是一种修复多种 HM 污染矿山土壤的有效策略，并为未来修复过程中土壤微环境响应的探索奠定了基础。
