Biodegradation of ofloxacin, norfloxacin, and ciprofloxacin as single and mixed substrates by Labrys portucalensis F11
- 1.3k Downloads
Fluoroquinolone (FQ) antibiotics are extensively used both in human and veterinary medicine, and their accumulation in the environment is causing an increasing concern. In this study, the biodegradation of the three most worldwide used FQs, namely ofloxacin, norfloxacin, and ciprofloxacin, by the fluoroorganic-degrading strain Labrys portucalensis F11 was assessed. Degradation occurred when the FQs were supplied individually or as mixture in the culture medium, in the presence of an easily degradable carbon source. Consumption of individual FQs was achieved at different extents depending on its initial concentration, ranging from 0.8 to 30 μM. For the lowest concentration, total uptake of each FQ was observed but stoichiometric fluoride release was not achieved. Intermediate compounds were detected and identified by LC-MS/MS with a quadrupole time of flight detector analyzer. Biotransformation of FQs by L. portucalensis mainly occurred through a cleavage of the piperazine ring and displacement of the fluorine substituent allowing the formation of intermediates with less antibacterial potency. FQ-degrading microorganisms could be useful for application in bioaugmentation processes towards more efficient removal of contaminants in wastewater treatment plants.
KeywordsFluoroquinolones Labrys portucalensis F11 Biodegradation Metabolites
C.L. Amorim, I.S. Moreira, and A.S. Maia wish to acknowledge a research grant from Fundação para a Ciência e Tecnologia (FCT), Portugal (ref. SFRH/BD/47109/2008, SFRH/BPD/87251/2012, and SFRH/BD/86939/2012, respectively) and Fundo Social Europeu (Programa Operacional Potencial Humano, Quadro de Referência Estratégico Nacional). This work was supported by FCT through the projects PTDC/EBB-EBI/111699/2009, CEQUIMED-Pest-OE/SAU/UI4040/2011, and PEst-OE/EQB/LA0016/2011.
- Calza P, Medana C, Carbone F, Giancotti V, Baiocchi C (2008) Characterization of intermediate compounds formed upon photoinduced degradation of quinolones by high-performance liquid chromatography/high-resolution multiple-stage mass spectrometry. Rapid Commun Mass Spectrom 22:1533–1552. doi: 10.1002/rcm PubMedCrossRefGoogle Scholar
- Halling-Sørensen B, Sengeløv G, Ingerslev F, Jensen LB (2003) Reduced antimicrobial potencies of oxytetracycline, tylosin, sulfadiazin, streptomycin, ciprofloxacin, and olaquindox due to environmental processes. Arch Environ Contam Toxicol 44:7–16. doi: 10.1007/s00244-002-1234-z PubMedCrossRefGoogle Scholar
- Lindberg RH, Olofsson U, Rendahl P, Johansson MI, Tysklind M, Andersson BA (2006) Behavior of fluoroquinolones and trimethoprim during mechanical, chemical, and active sludge treatment of sewage water and digestion of sludge. Environ Sci Technol 40:1042–1048. doi: 10.1021/es0516211 PubMedCrossRefGoogle Scholar
- Vasconcelos TG, Henriques DM, König A, Martins AF, Kümmerer K (2009) Photo-degradation of the antimicrobial ciprofloxacin at high pH: identification and biodegradability assessment of the primary by-products. Chemosphere 76:487–493. doi: 10.1016/j.chemosphere.2009.03.022 PubMedCrossRefGoogle Scholar
- Zhou NA, Lutovsky AC, Andaker GL, Gough HL, Ferguson JF (2013) Cultivation and characterization of bacterial isolates capable of degrading pharmaceutical and personal care products for improved removal in activated sludge wastewater treatment. Biodegrad. doi: 10.1007/s10532-013-9630-9 Google Scholar