Repositorio
Institucional

Diez, M. Cristina

Levio-Raiman, Marcela

Bornhardt, Cristian

Biodegradation of Iprodione and Chlorpyrifos Using an Immobilized Bacterial Consortium in a Packed-Bed Bioreactor

MDPI

MICROORGANISMS

en

This work provides the basis for implementing a continuous treatment system using a bacterial consortium for wastewater containing a pesticide mixture of iprodione (IPR) and chlorpyrifos (CHL). Two bacterial strains (Achromobacter spanius C1 and Pseudomonas rhodesiae C4) isolated from the biomixture of a biopurification system were able to efficiently remove pesticides IPR and CHL at different concentrations (10 to 100 mg L-1) from the liquid medium as individual strains and free consortium. The half-life time (T-1/2) for IPR and CHL was determined for individual strains and a free bacterial consortium. However, when the free bacterial consortium was used, a lower T-1/2 was obtained, especially for CHL. Based on these results, an immobilized bacterial consortium was formulated with each bacterial strain encapsulated individually in alginate beads. Then, different inoculum concentrations (5, 10, and 15% w/v) of the immobilized consortium were evaluated in batch experiments for IPR and CHL removal. The inoculum concentration of 15% w/v demonstrated the highest pesticide removal. Using this inoculum concentration, the packed-bed bioreactor with an immobilized bacterial consortium was operated in continuous mode at different flow rates (30, 60, and 90 mL h(-1)) at a pesticide concentration of 50 mg L-1 each. The performance in the bioreactor demonstrated that it is possible to efficiently remove a pesticide mixture of IPR and CHL in a continuous system. The metabolites 3,5-dichloroaniline (3,5-DCA) and 3,5,6-trichloro-2-pyridinol (TCP) were produced, and a slight accumulation of TCP was observed. The bioreactor was influenced by TCP accumulation but was able to recover performance quickly. Finally, after 60 days of operation, the removal efficiency was 96% for IPR and 82% for CHL. The findings of this study demonstrate that it is possible to remove IPR and CHL from pesticide-containing wastewater in a continuous system.

2023

artículo original

10.3390/microorganisms11010220

PDF

pesticides

biodegradation

chlorpyrifos

iprodione

immobilized bacterial consortium

packed-bed bioreactor

Microbiología

pesticidas

biodegradación

clorpirifos

iprodiona

consorcio bacteriano inmovilizado

biorreactor de lecho compacto

artículo original

versión publicada

CC BY 4.0

CC BY 4.0

acceso abierto

acceso abierto

WOS:000918990800001

verde# dorado

Microbiología

ANID 21171802

ANID FONDECYT 1211738

ANID FONDAP 15130015

UFRO DI22-2011,