| Title | Microbiome Composition and Dynamics of a Reductive/Oxidative Bioelectrochemical System for Perchloroethylene Removal: Effect of the Feeding Composition |
| Abstract | Chlorinated solvents still represent an environmental concern that requires sustainable and innovative bioremediation strategies. This study describes the microbiome composition of a novel bioelectrochemical system (BES) based on sequential reductive/oxidative dechlorination for complete perchloroethylene (PCE) removal occurring in two separate but sequential chambers. The BES has been tested under various feeding compositions [i.e., anaerobic mineral medium (MM), synthetic groundwater (SG), and real groundwater (RG)] differing in presence of sulfate, nitrate, and iron (III). In addition, the main biomarkers of the dechlorination process have been monitored in the system under various conditions. Among them, Dehalococcoides mccartyi 16S rRNA and reductive dehalogenase genes (tceA, bvcA, and vcrA) involved in anaerobic dechlorination have been quantified. The etnE and etnC genes involved in aerobic dechlorination have also been quantified. The feeding composition affected the microbiome, in particular when the BES was fed with RG. Sulfuricurvum, enriched in the reductive compartment, operated with MM and SG, suggesting complex interactions in the sulfur cycle mostly including sulfur oxidation occurring at the anodic counter electrode (MM) or coupled to nitrate reduction (SG). Moreover, the known Mycobacterium responsible for natural attenuation of VC by aerobic degradation was found abundant in the oxidative compartment fed with RG, which was in line with the high VC removal observed (92 +/- 2%). D. mccartyi was observed in all the tested conditions ranging from 8.78E + 06 (with RG) to 2.35E + 07 (with MM) 16S rRNA gene copies/L. tceA was found as the most abundant reductive dehalogenase gene in all the conditions explored (up to 2.46 E + 07 gene copies/L in MM). The microbiome dynamics and the occurrence of biomarkers of dechlorination, along with the kinetic performance of the system under various feeding conditions, suggested promising implications for the scale-up of the BES, which couples reductive with oxidative dechlorination to ensure the complete removal of highly chlorinated ethylene and mobile low-chlorinated by-products. |
| Source | Frontiers in microbiology 13 |
| Keywords | reductive dechlorinationoxidative dechlorinationbioelectroremediationchlorinated ethylenesgroundwater remediationPCE |
| Journal | Frontiers in microbiology |
| Editor | Frontiers Research Foundation,, Lausanne, Svizzera |
| Year | 2022 |
| Type | Articolo in rivista |
| DOI | 10.3389/fmicb.2022.951911 |
| Authors | Di Franca, Maria L.; Matturro, Bruna; Crognale, Simona; Zeppilli, Marco; Dell'Armi, Edoardo; Majone, Mauro; Petrangeli Papini, Marco; Rossetti, Simona |
| Text | 483807 2022 10.3389/fmicb.2022.951911 ISI Web of Science WOS 000835220200001 reductive dechlorination oxidative dechlorination bioelectroremediation chlorinated ethylenes groundwater remediation PCE Microbiome Composition and Dynamics of a Reductive/Oxidative Bioelectrochemical System for Perchloroethylene Removal Effect of the Feeding Composition Di Franca, Maria L.; Matturro, Bruna; Crognale, Simona; Zeppilli, Marco; Dell Armi, Edoardo; Majone, Mauro; Petrangeli Papini, Marco; Rossetti, Simona IRSA CNR; Sapienza Universita Rome Chlorinated solvents still represent an environmental concern that requires sustainable and innovative bioremediation strategies. This study describes the microbiome composition of a novel bioelectrochemical system BES based on sequential reductive/oxidative dechlorination for complete perchloroethylene PCE removal occurring in two separate but sequential chambers. The BES has been tested under various feeding compositions i.e., anaerobic mineral medium MM , synthetic groundwater SG , and real groundwater RG differing in presence of sulfate, nitrate, and iron III . In addition, the main biomarkers of the dechlorination process have been monitored in the system under various conditions. Among them, Dehalococcoides mccartyi 16S rRNA and reductive dehalogenase genes tceA, bvcA, and vcrA involved in anaerobic dechlorination have been quantified. The etnE and etnC genes involved in aerobic dechlorination have also been quantified. The feeding composition affected the microbiome, in particular when the BES was fed with RG. Sulfuricurvum, enriched in the reductive compartment, operated with MM and SG, suggesting complex interactions in the sulfur cycle mostly including sulfur oxidation occurring at the anodic counter electrode MM or coupled to nitrate reduction SG . Moreover, the known Mycobacterium responsible for natural attenuation of VC by aerobic degradation was found abundant in the oxidative compartment fed with RG, which was in line with the high VC removal observed 92 / 2% . D. mccartyi was observed in all the tested conditions ranging from 8.78E 06 with RG to 2.35E 07 with MM 16S rRNA gene copies/L. tceA was found as the most abundant reductive dehalogenase gene in all the conditions explored up to 2.46 E 07 gene copies/L in MM . The microbiome dynamics and the occurrence of biomarkers of dechlorination, along with the kinetic performance of the system under various feeding conditions, suggested promising implications for the scale up of the BES, which couples reductive with oxidative dechlorination to ensure the complete removal of highly chlorinated ethylene and mobile low chlorinated by products. 13 Published version Articolo 14_Matturrro et al2022.pdf Articolo in rivista Frontiers Research Foundation, 1664 302X Frontiers in microbiology Frontiers in microbiology Front. microbiol. Frontiers in microbiology simona.rossetti ROSSETTI SIMONA bruna.matturro MATTURRO BRUNA simona.crognale CROGNALE SIMONA ELECTRA Electricity driven Low Energy and Chemical input Technology foR Accelerated bioremediation |
