Utjecaj diklofenaka na bakterijsku populaciju aktivnog mulja u reaktoru s pritokom supstrata
| Autor: | Ines Mandic-Mulec, Barbara Kraigher |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2020 |
| Předmět: |
0106 biological sciences
General Chemical Engineering lcsh:Biotechnology pharmaceuticals 01 natural sciences Industrial and Manufacturing Engineering Agar plate 010608 biotechnology Arthrobacter Pseudomonas lcsh:TP248.13-248.65 activated sludge Food science Original Scientific Papers Comamonas diclofenac bacterial community T-RFLP biology lcsh:TP368-456 Chemistry aktivni mulj farmaceutski proizvodi diklofenak T-RFLP identifikacija bakterija u populaciji biology.organism_classification Terminal restriction fragment length polymorphism lcsh:Food processing and manufacture Activated sludge Wastewater Nitrification Sewage treatment Food Science Biotechnology |
| Zdroj: | Food Technology and Biotechnology, Vol 58, Iss 4, Pp 402-410 (2020) Food Technology and Biotechnology Volume 58 Issue 4 |
| ISSN: | 1334-2606 1330-9862 |
| Popis: | Research background. The occurrence and environmental toxicity of pharmaceuticals have recently attracted increasing attention. Diclofenac is a highly consumed non-steroidal anti-inflammatory drug, which is often detected in wastewaters, but investigations of its influence on bacteria are scarce. Experimental approach. We investigated the influence of this pharmaceutical on bacterial community in activated sludge exposed to increasing concentrations of diclofenac in fed-batch reactors over 41 days. Nitrification activity of the activated sludge was measured and changes in bacterial community structure were followed using culture-independent molecular method (terminal restriction fragment length polymorphism, T-RFLP) and by the cultivation approach. Results and conclusions. Nitrification activity was not detectably influenced by addition of diclofenac, while the main change of the bacterial community structure was detected only at the end of incubation (after 41 days) when diclofenac was added to artificial wastewater as the only carbon source. Changes in community composition due to enrichment were also observed using cultivation approach. However, taxonomic affiliation of isolates did not match taxons identified by T-RFLP community profiling. Isolates obtained from inoculum activated sludge belonged to five genera: Comamonas, Arthrobacter, Acinetobacter, Citrobacter and Aeromonas, known for their potential to degrade aromatic compounds. However, only Pseudomonas species were isolated after the last enrichment step on minimal agar plates with diclofenac added as the sole carbon source. Novelty and scientific contribution. Our results suggested that the selected recalcitrant and commonly detected pharmaceutical does not strongly influence the sensitive and important nitrification process of wastewater treatment neither. Moreover, the isolated strains obtained after enrichment procedure that were able to grow on minimal agar plates with diclofenac added as the only carbon source could serve as potential model bacteria to study bacterial diclofenac degradation. Pozadina istraživanja. U zadnje vrijeme prisutnost i toksičnost farmaceutskih proizvoda u okolišu pobuđuju veliki interes javnosti. Diklofenak je nesteroidni protuupalni lijek koji se uvelike koristi, pa često dospijeva u otpadne vode, no usprkos tome postoji vrlo malo istraživanja o njegovom utjecaju na bakterije aktivnog mulja. Eksperimentalni pristup. Ispitali smo utjecaj ovog lijeka na bakterijsku populaciju aktivnog mulja u reaktoru s pritokom supstrata kojem smo dodavali diklofenak tijekom 41 dana. Izmjerena je nitrifikacijska aktivnost bakterija aktivnog mulja, a promjena sastava bakterijske populacije praćena je molekularnom metodom za izravnu identifikaciju (T-RFLP) te uzgojem bakterija. Rezultati i zaključci. Dodatak diklofenaka nije vidljivo utjecao na nitrifikacijsku aktivnost bakterija, a veća je promjena sastava bakterijske populacije opažena tek na kraju inkubacije (nakon 41 dana), kad je diklofenak bio dodan kao jedini izvor ugljika u otopinu koja simulira sastav otpadnih voda. Promjene sastava bakterijske populacije nakon obogaćivanja podloge diklofenakom primijećene su nakon izolacije i praćenja rasta bakterija na minimalnoj podlozi. Međutim, taksonomska pripadnost izolata nije odgovarala taksonima identificiranim metodom T-RFLP. Izolati dobiveni iz aktivnog mulja te korišteni kao inokulum spadali su u pet rodova bakterija: Comamonas, Arthrobacter, Acinetobacter, Citrobacter i Aeromonas, koje su poznate po sposobnosti razgradnje aromatskih spojeva. Međutim, nakon posljednjeg dodatka diklofenaka kao jedinog izvora ugljika minimalnoj podlozi izolirane su jedino bakterije vrste Pseudomonas. Novina i znanstveni doprinos. Rezultati pokazuju da ispitani lijek, koji ima ograničenu biorazgradivost a često ga nalazimo u otpadnim vodama, ne utječe u velikoj mjeri na osjetljiv i bitan postupak nitrifikacije otpadnih voda. Osim toga, zaključeno je da izolirani sojevi bakterija koji su rasli na minimalnoj podlozi s diklofenakom kao jedinim izvorom ugljika mogu poslužiti kao model za proučavanje bakterijske razgradnje diklofenaka. |
| Databáze: | OpenAIRE |
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