Shen Rui, Yu Ling, Xu Pan, Liang Zhiwei, Lu Qihong, Liang Dawei, He Zhili, Wang Shanquan
Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-Sen University, Guangzhou, 510006, China.
Analysis and Test Center, Guangdong University of Technology, Guangzhou, 510006, China.
Chemosphere. 2021 Mar;267:129152. doi: 10.1016/j.chemosphere.2020.129152. Epub 2020 Dec 1.
Organohalide-respiring bacteria (OHRB) remove halogens from a variety of organohalides, which have been utilized for in situ remediation of different contaminated sites, e.g., groundwater, sediment and soil. Nonetheless, dehalogenation activities of OHRB and consequent remediation efficiencies can be synergistically affected by water content, soil type and inoculated/indigenous OHRB, which need to be disentangled to identify the key driving parameter and to elucidate the underlying mechanism. In this study, we investigated the impacts of water content (0-100%), soil type (laterite, brown soil and black soil) and inoculated OHRB (Dehalococcoides mccartyi CG1 and a river sediment culture) on reductive dechlorination of perchloroethene (PCE) and polychlorinated biphenyls (PCBs), as well as on associated microbial communities. Results suggested that the water content as a primary rate-limiting parameter governed dechlorination activities in environmental matrices, particularly in the soil, possibly through mediation of cell-to-organohalide mobility of OHRB. By contrast, interestingly, organohalide-dechlorinating microbial communities were predominantly clustered based on soil types, rather than water contents or inoculated OHRB. This study provided knowledge on the impacts of major parameters on OHRB-mediated reductive dechlorination in groundwater, sediment and soil for future optimization of in situ bioremediation of organohalides.
有机卤呼吸细菌（OHRB）可从多种有机卤化物中去除卤素，这些有机卤化物已被用于不同污染场地（如地下水、沉积物和土壤）的原位修复。然而，OHRB的脱卤活性以及随之而来的修复效率会受到含水量、土壤类型以及接种/本地OHRB的协同影响，需要理清这些因素以确定关键驱动参数并阐明潜在机制。在本研究中，我们调查了含水量（0 - 100%）、土壤类型（红土、棕壤和黑土）以及接种的OHRB（麦氏脱卤球菌CG1和一种河流沉积物培养物）对全氯乙烯（PCE）和多氯联苯（PCBs）的还原脱氯作用以及相关微生物群落的影响。结果表明，含水量作为主要的限速参数控制着环境基质中的脱氯活性，尤其是在土壤中，可能是通过调节OHRB的细胞到有机卤化物的迁移来实现的。相比之下，有趣的是，有机卤脱氯微生物群落主要根据土壤类型聚类，而不是含水量或接种的OHRB。本研究提供了关于主要参数对地下水、沉积物和土壤中OHRB介导的还原脱氯作用影响的知识，以便未来优化有机卤化物的原位生物修复。
