Co-metabolic degradation of the antibiotic ciprofloxacin by the enriched bacterial consortium XG and its bacterial community composition

Nai-Xian FENG, Jiao YU, Lei XIANG, Le-Yi YU, Hai-Ming ZHAO, Ce-Hui MO, Yan-Wen LI, Quan-Ying CAI, Ming Hung WONG, Qing X. LI

Research output: Contribution to journalArticle

Abstract

Ciprofloxacin is a broad spectral and highly refractory antibiotic. It is an emerging pollutant. This study aimed to utilise co-metabolism as a means to degrade ciprofloxacin by a bacterial consortium. The stable bacterial consortium XG capable of efficiently degrading ciprofloxacin was successfully established through successive acclimation of indigenous microorganisms. The consortium XG was primarily consisted of Achromobacter, Bacillus, Lactococcus, Ochrobactrum, and Enterococcus as well as at least other five minor genera. A novel strain YJ17 with CIP-degrading ability was isolated from the consortium and identified as Ochrobactrum sp. The consortium XG utilised amino acids, carbohydrates, and carboxylic acids at a rate approximately 16.6–243-fold greater than the other carbon substrates, but only slow utilisation of ciprofloxacin as a sole carbon source. Ciprofloxacin can be co-metabolized along with many carbon sources, attaining degradation rates up to 63%. Glycyl-l-glutamic acid, d-cellobiose, and itaconic acid are among the substrates most favourable for co-metabolism. The metabolites of ciprofloxacin were identified by LC-QTOF-MS. Co-metabolic degradation of ciprofloxacin by consortium XG led to the removal of essential functional groups from parent compound, thus resulting in formation of metabolites with less bioactive potency. Finally, a possible biochemical pathway for the degradation of ciprofloxacin was proposed. Consortium XG possesses high potential for bioremediation of ciprofloxacin-contaminated environments in the presence of a co-substrate. Copyright © 2019 Elsevier B.V. All rights reserved.
Original languageEnglish
Pages (from-to)41-51
JournalScience of the Total Environment
Volume665
Early online dateFeb 2019
DOIs
Publication statusE-pub ahead of print - Feb 2019

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Antibiotics
Ciprofloxacin
antibiotics
community composition
Metabolites
Anti-Bacterial Agents
Metabolism
substrate
Degradation
degradation
Carbon
metabolite
carbon
Substrates
metabolism
Chemical analysis
Acids
Bioremediation
acid
Bacilli

Bibliographical note

Feng, N.-X., Yu, J., Xiang, L., Yu, L.-Y., Zhao, H.-M., Mo, C.-H., . . . Li, Q. X. (2019). Co-metabolic degradation of the antibiotic ciprofloxacin by the enriched bacterial consortium XG and its bacterial community composition. Science of The Total Environment, 665, 41-51. doi: 10.1016/j.scitotenv.2019.01.322

Keywords

  • Ciprofloxacin
  • Acclimation
  • Consortium
  • High-throughput sequencing
  • Co-metabolism