Advanced search
1 file | 197.69 KB

Photocatalytic degradation of the antibiotic moxifloxacin: a deeper look at the degradation products and residual antibacterial activity

Author
Organization
Abstract
Fluoroquinolones (FQ) are a family of synthetic, broad-spectrum antibacterial compounds, used in a variety of human and veterinary applications. Due to their increasing consumption more of the compounds are detected in effluent waters of wastewater treatment plants. Since activated sludge and adsorption using activated carbon come short in the efficient removal of these rather persistent molecules, other techniques like advanced oxidation processes (AOPs) are needed. In house experiments with AOPs like ozonation and sonolysis show that these physical-chemical techniques are promising for the treatment of effluent waters loaded with biorecalcitrant antibiotics (Dewitte et al., 2008; De Bel et al., 2009). In this study, heterogeneous photocatalysis is used for the degradation of the third generation fluoroquinolone moxifloxacin (MOX) in a lab-scale batch reactor. In a first part, the objective is to bring new insights in the photocatalytic degradation pathway of this antibiotic. During photocatalytic treatment, different degradation products are detected by liquid chromatography coupled to low resolution mass spectrometry. Identification of the detected products is done using high resolution magnetic sector mass spectrometry, and chemical structures are elucidated using accurate mass, double bond equivalent and the molecular composition of the mother compound. In a second part, the residual antibacterial activity is investigated by means of agar diffusion tests for four bacterial species selected from the antibacterial spectrum of MOX. From a dosis-respons test using a range of MOX concentrations and the agar diffusion tests with the photocatalytic samples, it can be concluded that the residual concentration of mother compound in solution correlates well with the residual antibacterial activity. Only for E. coli at lower liquid concentrations a higher inhibition is noticed. This could be the result of the formed degradation products which still exert some antibacterial activity toward E. coli. After 12 minutes of photocatalytic degradation using UVA irradiation, no residual inhibition could be observed for the selected bacterial species.
Keywords
fluoroquinolone, Heterogeneous photocatalysis, degradation products, antibacterial activity, CIPROFLOXACIN, PHARMACEUTICALS, IDENTIFICATION, OZONATION, WATER, PH

Downloads

  • (...).pdf
    • full text
    • |
    • UGent only
    • |
    • PDF
    • |
    • 197.69 KB

Citation

Please use this url to cite or link to this publication:

Chicago
Van Doorslaer, Xander, Kristof Demeestere, Philippe Heynderickx, Marieke Caussyn, Herman Van Langenhove, Frank Devlieghere, An Vermeulen, and Jo Dewulf. 2013. “Photocatalytic Degradation of the Antibiotic Moxifloxacin: a Deeper Look at the Degradation Products and Residual Antibacterial Activity.” In Proceedings of the 13th International Conference on Environmental Science and Technology, ed. TD Lekkas. Athens, Greece: Global Nest.
APA
Van Doorslaer, X., Demeestere, K., Heynderickx, P., Caussyn, M., Van Langenhove, H., Devlieghere, F., Vermeulen, A., et al. (2013). Photocatalytic degradation of the antibiotic moxifloxacin: a deeper look at the degradation products and residual antibacterial activity. In T. Lekkas (Ed.), Proceedings of the 13th International conference on Environmental Science and Technology. Presented at the 13th International conference on Environmental Science and Technology (CEST 2013), Athens, Greece: Global Nest.
Vancouver
1.
Van Doorslaer X, Demeestere K, Heynderickx P, Caussyn M, Van Langenhove H, Devlieghere F, et al. Photocatalytic degradation of the antibiotic moxifloxacin: a deeper look at the degradation products and residual antibacterial activity. In: Lekkas T, editor. Proceedings of the 13th International conference on Environmental Science and Technology. Athens, Greece: Global Nest; 2013.
MLA
Van Doorslaer, Xander, Kristof Demeestere, Philippe Heynderickx, et al. “Photocatalytic Degradation of the Antibiotic Moxifloxacin: a Deeper Look at the Degradation Products and Residual Antibacterial Activity.” Proceedings of the 13th International Conference on Environmental Science and Technology. Ed. TD Lekkas. Athens, Greece: Global Nest, 2013. Print.
@inproceedings{4250953,
  abstract     = {Fluoroquinolones (FQ) are a family of synthetic, broad-spectrum antibacterial compounds, used in a variety of human and veterinary applications. Due to their increasing consumption more of the compounds are detected in effluent waters of wastewater treatment plants. Since activated sludge and adsorption using activated carbon come short in the efficient removal of these rather persistent molecules, other techniques like advanced oxidation processes (AOPs) are needed. In house experiments with AOPs like ozonation and sonolysis show that these physical-chemical techniques are promising for the treatment of effluent waters loaded with biorecalcitrant antibiotics (Dewitte et al., 2008; De Bel et al., 2009). 
In this study, heterogeneous photocatalysis is used for the degradation of the third generation fluoroquinolone moxifloxacin (MOX) in a lab-scale batch reactor. In a first part, the objective is to bring new insights in the photocatalytic degradation pathway of this antibiotic. During photocatalytic treatment, different degradation products are detected by liquid chromatography coupled to low resolution mass spectrometry. Identification of the detected products is done using high resolution magnetic sector mass spectrometry, and chemical structures are elucidated using accurate mass, double bond equivalent and the molecular composition of the mother compound. 
In a second part, the residual antibacterial activity is investigated by means of agar diffusion tests for four bacterial species selected from the antibacterial spectrum of MOX. From a dosis-respons test using a range of MOX concentrations and the agar diffusion tests with the photocatalytic samples, it can be concluded that the residual concentration of mother compound in solution correlates well with the residual antibacterial activity. Only for E. coli at lower liquid concentrations a higher inhibition is noticed. This could be the result of the formed degradation products which still exert some antibacterial activity toward E. coli. After 12 minutes of photocatalytic degradation using UVA irradiation, no residual inhibition could be observed for the selected bacterial species.},
  articleno    = {CEST2013\_0703},
  author       = {Van Doorslaer, Xander and Demeestere, Kristof and Heynderickx, Philippe and Caussyn, Marieke and Van Langenhove, Herman and Devlieghere, Frank and Vermeulen, An and Dewulf, Jo},
  booktitle    = {Proceedings of the 13th International conference on Environmental Science and Technology},
  editor       = {Lekkas, TD},
  isbn         = {9789607475510},
  issn         = {1106-5516},
  language     = {eng},
  location     = {Athens, Greece},
  pages        = {6},
  publisher    = {Global Nest},
  title        = {Photocatalytic degradation of the antibiotic moxifloxacin: a deeper look at the degradation products and residual antibacterial activity},
  year         = {2013},
}

Web of Science
Times cited: