Degradation of Fluoroquinolone Antibiotics and Identification of Metabolites/Tr...

• Author(s): Maia, Alexandra S. ; Ribeiro, Ana R. ; Amorim, Catarina L. ; Barreiro, Juliana C. ; Cass, Quezia B. ; Castro, Paula M.L. ; Tiritan, Maria E.
• Date: 2013
• Persistent ID: http://hdl.handle.net/10400.14/13242
• Origin: Veritati - Repositório Institucional da Universidade Católica Portuguesa
• Subject(s): biodegradation; fluoroquinolones; LC-MS/MS; metabolites
• Document Type: Article
• Language: English

Description

Antibiotics are a therapeutic class widely found inenvironmental matrices and extensively studied due to its persistence and implications for multi-resistant bacteria development. Degradation of four fluoroquinolone antibiotics, namely Ofloxacin (OFL), Norfloxacin (NOR), Ciprofloxacin (CPF) and Moxifloxacin (MOX), at 10 mg L-1 using a mixed bacterial culture, was assessed for 60 days. The assays were followed by a developed and validated analytical method of HPLC with Fluorescence Detection using a Luna PFP (2) 3µm column. The optimized conditions allowed picturing metabolites/transformation products formation and accumulation during the process, stating an incomplete mineralization, also shown byfluoride release. OFL and MOX presented the highest (98.3%) and the lowest (80.5%) extent of degradation after 19 days of assay, respectively. Some of these intermediate compounds were identified by LCMS/MS in selected degradation samples. Most of the intermediates were already described as biodegradation and/or photodegradationproducts in different conditions, but new and/or unknown metabolites were also present.