Use of a biostimulant obtained from okara in the bioremediation of a soil polluted by used motor car oil

In this manuscript we studied in the laboratory the bioremediation effects of a biostimulant obtained from okara by enzymatic hydrolysis processes in a soil polluted with used motor-car oil at a rate of 1 % (w/w) over an 89-day period. The biostimulant was added to the soil 6 times during the incuba...

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Detalles Bibliográficos
Autores: Paneque Macías, Patricia Isabel, Caballero, Pablo, Parrado, Juan, Gómez Parrales, Isidoro Ángel, Tejada, Manuel
Tipo de recurso: artículo
Estado:Versión enviada para evaluación y publicación
Fecha de publicación:2020
País:España
Institución:Universidad de Sevilla (US)
Repositorio:idUS. Depósito de Investigación de la Universidad de Sevilla
OAI Identifier:oai:idus.us.es:11441/155039
Acceso en línea:https://hdl.handle.net/11441/155039
https://doi.org/10.1016/j.jhazmat.2019.121820
Access Level:acceso abierto
Palabra clave:okara biostimulant
used motor-car oil
polycyclic aromatic hydrocarbons
total heavy metals
soil dehydrogenase activity
Descripción
Sumario:In this manuscript we studied in the laboratory the bioremediation effects of a biostimulant obtained from okara by enzymatic hydrolysis processes in a soil polluted with used motor-car oil at a rate of 1 % (w/w) over an 89-day period. The biostimulant was added to the soil 6 times during the incubation period at a rate of 2 %. Dehydrogenase activity and the evolution of polycyclic aromatic hydrocarbons (PAHs) and pseudo total heavy metals in soil were studied. The successive applications of the biostimulant to the polluted soil gradually increased PAHs degradation during the experimental period. Thus, at the end of the experiment, the application of the biostimulant decreased the concentration of naphthalene in soil by 74 %, while PAHs with 3, 4, 5 and 6 aromatic rings had been reduced by around 58 %, 44 %, 30 % and 23 %, respectively. This degradation is possibly due to the high number of low molecular weight peptides (<300 Da) in the biostimulant which are readily available for PAHs-tolerant soil microorganisms that accelerate the degradation of the said toxins. The concentration of heavy metals in the oil used was not very high and consequently the dehydrogenase activity was not negatively affected.