Role of indigenous microbiota from heavily contaminated sediments in the bioprecipitation of arsenic Autor

"High arsenic concentrations have been detected in alluvial aquifers of arid and semi-arid zones in Mexico. This work describes the potential of microbial arsenate reduction of the indigenous community present in sediments from an arsenic contaminated aquifer. Microcosms assays were conducted t...

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Detalles Bibliográficos
Autores: ERIKA ELIZABETH RIOS VALENCIANA, ROBERTO BRIONES GALLARDO, Luis Felipe Cházaro Ruiz, NADIA VALENTINA MARTINEZ VILLEGAS, María de Lourdes Berenice Celis García
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2017
País:México
Institución:Instituto Potosino de Investigación Científica y Tecnológica
Repositorio:Repositorio Institucional del IPICYT
OAI Identifier:oai:ipicyt.repositorioinstitucional.mx:1010/2077
Acceso en línea:http://ipicyt.repositorioinstitucional.mx/jspui/handle/1010/2077
Access Level:acceso abierto
Palabra clave:info:eu-repo/classification/Autor/Arsenate
info:eu-repo/classification/Autor/Bioprecipitation
info:eu-repo/classification/Autor/Sediment
info:eu-repo/classification/Autor/Sulfate
info:eu-repo/classification/Autor/Reduction
info:eu-repo/classification/cti/7
Descripción
Sumario:"High arsenic concentrations have been detected in alluvial aquifers of arid and semi-arid zones in Mexico. This work describes the potential of microbial arsenate reduction of the indigenous community present in sediments from an arsenic contaminated aquifer. Microcosms assays were conducted to evaluate arsenate and sulfate-reducing activities of the native microbiota. Two different sediments were used as inoculum in the assays amended with lactate (10 mM) as electron donor and with sulfate and arsenate (10 mM each) as electron acceptors. Sediments were distinguished by their concentration of total arsenic 238.3 ± 4.1 mg/kg or 2263.1 ± 167.7 mg/kg, which may be considered as highly contaminated sediments with arsenic. Microbial communities present in both sediments were able to carry out arsenate reduction, accomplished within 4 days, with the corresponding formation of arsenite; sulfate reduction took place as well. Both reducing activities occurred without previous acclimation period or enrichment, even at potential inhibitory concentrations of arsenate as high as 750 mg/L (10 mM). The formation of a yellowish colloidal precipitate was evident when both reducing processes occurred in the microcosm, which contributed to remove between 52 and 90.9% of As(III) from the liquid phase by bioprecipitation of arsenic as arsenic sulfide."