Please use this identifier to cite or link to this item: https://hdl.handle.net/10216/120534
Author(s): Alexandrino D.A.M.
Mucha A.P.
Almeida C.M.
Gao W.
Jia Z.
Carvalho M.F.
Title: Biodegradation of the veterinary antibiotics enrofloxacin and ceftiofur and associated microbial community dynamics
Publisher: Elsevier
Issue Date: 2017
Abstract: Fluoroquinolones and cephalosporins are two classes of veterinary antibiotics arising as pollutants of emerging concern. In this work, the microbial degradation of two representative antibiotics of both these classes, enrofloxacin (ENR) and ceftiofur (CEF), is reported. Biodegradation of the target antibiotics was investigated by supplementing the culture medium with ENR and CEF, individually and in mixture. Microbial inocula were obtained from rhizosphere sediments of plants derived from experimental constructed wetlands designed for the treatment of livestock wastewaters contaminated with trace amounts of these antibiotics. Selected microbial inocula were acclimated during a period of 5 months, where the antibiotics were supplemented every three weeks at the concentration of 1 mg L− 1, using acetate as a co-substrate. After this period, the acclimated consortia were investigated for their capacity to biodegrade 2 and 3 mg L− 1 of ENR and CEF. Complete removal of CEF from the inoculated culture medium was always observed within 21 days, independently of its concentration or the concomitant presence of ENR. Biodegradation of ENR decreased with the increase in its concentration in the culture medium, with defluorination percentages decreasing from ca. 65 to 4%. Ciprofloxacin and norfloxacin were detected as biodegradation intermediates of ENR in the microbial cultures supplemented with this antibiotic, indicating that defluorination of at least part of ENR in these cultures is not an immediate catabolic step. Abiotic mechanisms showed high influence in the removal of CEF, affecting less ENR degradation. The acclimation process with the target antibiotics led to significant shifts in the structure and diversity of the microbial communities, predominantly selecting microorganisms belonging to the phyla Proteobacteria (e.g. Achromobacter, Variovorax and Stenotrophomonas genera) and Bacteroidetes (e.g. Dysgonomonas, Flavobacterium and Chryseobacterium genera). The results presented in this study indicate that biodegradation can be an important mechanism for the environmental removal of the tested compounds. © 2016 Elsevier
Subject: Agriculture
Antibiotics
Drug products
Microorganisms
Soils
Wastewater treatment
Wetlands
Ceftiofur
Constructed wetlands
Enrofloxacin
Metagenomics
Microbial communities
Microbial community dynamics
Microbial degradation
Veterinary antibiotic
Biodegradation
acetic acid
ceftiofur
ciprofloxacin
enrofloxacin
norfloxacin
veterinary drug
antibiotics
biodegradation
community dynamics
concentration (composition)
genomics
microbial community
abiotic stress
acclimatization
Article
Bacteroidetes
catabolism
community dynamics
community structure
constructed wetland
controlled study
culture medium
defluorination
livestock
metagenomics
microbial community
microbial degradation
microbial diversity
nonhuman
Proteobacteria
rhizosphere inoculation
waste component removal
waste water
water contamination
Achromobacter
Bacteroidetes
Chryseobacterium
Dysgonomonas
Flavobacterium
Proteobacteria
Stenotrophomonas
Variovorax
URI: https://hdl.handle.net/10216/120534
Source: Science of the Total Environment, vol. 581-582, p. 359-368
Document Type: Artigo em Revista Científica Internacional
Rights: restrictedAccess
Appears in Collections:CIIMAR - Artigo em Revista Científica Internacional

Files in This Item:
File Description SizeFormat 
Alexandrino DAM_2_2017.pdf
  Restricted Access
829.28 kBAdobe PDF    Request a copy


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.