| Abstract | Antibiotics are emerging contaminants, which wing to their bioactivity, may lead to short-term and long-term alterations of natural microbial communities in aquatic environment. We investigated the effects of antibiotics on biofilm bacterial communities in the Llobregat River (Northeast Spain). Three sampling sites were selected: two less polluted sites and one hotspot. River water was collected from each site and used both as inoculum and medium for growing biofilms in independent mesocosms. After 25 d of biofilm colonization, we exposed the colonized biofilms to river waters from the downstream sites (progressively contaminated by antibiotics). A control from each site was maintained where the growing biofilm was always exposed to water from the same site. The bacterial community composition, bacterial live/dead ratio and extracellular enzyme activities of the biofilms were measured before and 9 d after exposing the biofilms to increasing contaminated waters. Sixteen antibiotic compounds were detected in the water from the three sampling sites. At each site, the antibiotics present in the highest concentrations were sulfonamides, followed by quinolones and macrolides. Bacterial communities of biofilms grown with the three river waters differed markedly in their structure, but less so in terms of functional descriptors. After switching the medium water to increasing pollution, biofilms exhibited increased levels of actinobacteria (HGC), a trend that was associated to the higher antibiotic concentrations in the water. These biofilms also showed increased bacterial mortality, and decreased extracellular leucine-aminopeptidase and alkaline phosphatase. There was a significant correlation between antibiotic concentrations and biofilm responses. Our results indicate that the continuous entrance of antibiotics in running waters cause significant structural and functional changes in microbial attached communities |
| Authors | Proia L., Lupini G., Osorio V., Perez S., Barcelo D., Schwartz T., Amalfitano S., Fazi S., Romani A.M., Sabater S. |
| Text | 223271 2013 10.1016/j.chemosphere.2013.01.063 Antibiotics Biofilms Mediterranean river Bacteria CARD FISH Response of biofilm bacterial communities to antibiotic pollutants in a Mediterranean river Proia L., Lupini G., Osorio V., Perez S., Barcelo D., Schwartz T., Amalfitano S., Fazi S., Romani A.M., Sabater S. Institute of Aquatic Ecology, University of Girona IEA UdG , Campus Montilivi, 17071 Girona, Spain Water Research Institute, National Research Council of Italy IRSA CNR , Rome, Italy Department of Environmental Chemistry, Institute of Environmental Assessment and Water Research, Spanish National Research Council IDAEA CSIC , Barcelona, Spain Karlsruhe Institute of Technology, Institute of Functional Interfaces, Department of Microbiology of Natural and Technical Interfaces, Karlsruhe, Germany Catalan Institute for Water Research ICRA , Girona, Spain Antibiotics are emerging contaminants, which wing to their bioactivity, may lead to short term and long term alterations of natural microbial communities in aquatic environment. We investigated the effects of antibiotics on biofilm bacterial communities in the Llobregat River Northeast Spain . Three sampling sites were selected two less polluted sites and one hotspot. River water was collected from each site and used both as inoculum and medium for growing biofilms in independent mesocosms. After 25 d of biofilm colonization, we exposed the colonized biofilms to river waters from the downstream sites progressively contaminated by antibiotics . A control from each site was maintained where the growing biofilm was always exposed to water from the same site. The bacterial community composition, bacterial live/dead ratio and extracellular enzyme activities of the biofilms were measured before and 9 d after exposing the biofilms to increasing contaminated waters. Sixteen antibiotic compounds were detected in the water from the three sampling sites. At each site, the antibiotics present in the highest concentrations were sulfonamides, followed by quinolones and macrolides. Bacterial communities of biofilms grown with the three river waters differed markedly in their structure, but less so in terms of functional descriptors. After switching the medium water to increasing pollution, biofilms exhibited increased levels of actinobacteria HGC , a trend that was associated to the higher antibiotic concentrations in the water. These biofilms also showed increased bacterial mortality, and decreased extracellular leucine aminopeptidase and alkaline phosphatase. There was a significant correlation between antibiotic concentrations and biofilm responses. Our results indicate that the continuous entrance of antibiotics in running waters cause significant structural and functional changes in microbial attached communities Articolo on line Articolo_1.pdf Articolo in rivista Elsevier 0045 6535 Chemosphere Chemosphere Chemosphere Chemosphere. Chemosphere. Environmental chemistry, Chemosphere. Persistent organic pollutants and dioxins, Chemosphere. Environmental toxicology and risk assessment, Chemosphere. Science for Environmental toxicology, LUPINI GIULIANO stefano.fazi FAZI STEFANO stefano.amalfitano AMALFITANO STEFANO TA.P04.032.002 Ruolo delle comunita microbiche nei cicli biogeochimici e nella degradazione degli inquinanti |
