Tetracyclines lead to ammonium accumulation during nitrification process.
J Environ Sci Health A Tox Hazard Subst Environ Eng
; 55(8): 1021-1031, 2020.
Article
en En
| MEDLINE
| ID: mdl-32406796
ABSTRACT
The effect of tetracyclines used for swine food-production (tetracycline and oxytetracycline) on enriched nitrifying bacteria cultures over time was investigated in this study. Short-term exposure assays were performed in different concentrations of each antibiotic, using ammonia oxidizing bacteria (AOB) culture and nitrifying bacteria. The results pointed out a higher inhibitory effect of tetracycline on both bacterial communities. The AOB was more sensitive to antibiotic exposure when compared to the nitrifying culture. Although high antibiotic concentrations were applied, the half maximal inhibitory concentration (IC50) was achieved only for the AOB culture exposed to tetracycline at a concentration of 273 mg L-1. Nonetheless, the long-term exposure assay demonstrated a reduction of the tetracycline inhibition effect against AOB. The exposure to 100 mg L-1 of tetracycline (TC) did not show relevant influence over ammonium conversion efficiency; however, at 128 mg L-1 of TC, the efficiency decreased from 94% to 72%. Further investigation revealed that TC reduced the final effluent quality due to the development of a resistance mechanism by AOB culture against this antibiotic. This mechanism involves increasing the excretion of extracellular polymeric substances (EPS) and soluble microbial products (SMP), which probably increases BOD, and reduces ammonia consumption by the bacterial culture.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Aguas del Alcantarillado
/
Tetraciclinas
/
Purificación del Agua
/
Drogas Veterinarias
/
Nitrificación
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Aguas Residuales
/
Compuestos de Amonio
Límite:
Animals
Idioma:
En
Revista:
J Environ Sci Health A Tox Hazard Subst Environ Eng
Asunto de la revista:
TOXICOLOGIA
Año:
2020
Tipo del documento:
Article
País de afiliación:
Brasil