TY - JOUR
T1 - Diclofenac biotransformation in the enhanced biological phosphorus removal process
AU - Kolakovic, Srdana
AU - Salgado, Ricardo
AU - Freitas, Elisabete B.
AU - Bronze, Maria R.
AU - Sekulic, Maja Turk
AU - Carvalho, Gilda
AU - Reis, Maria A. M.
AU - Oehmen, Adrian
N1 - Funding Information:
info:eu-repo/grantAgreement/FCT/6817 - DCRRNI ID/UIDP%2F04378%2F2020/PT#
info:eu-repo/grantAgreement/FCT/6817 - DCRRNI ID/UIDB%2F04378%2F2020/PT#
of the Research Units on Applied Molecular Biosciences ? UCIBIO, LAQV (UID/QUI/50006/2020) and the project LA/P/0140/2020 of the Associate Laboratory Institute for Health and Bioeconomy - i4HB. Srdana Kolakovic acknowledges European Commission (Water JPI project 196 in the WaterWorks2014 ERA-NET Co-funded Call) for the ?WATINTECH? project grant and Sigma Agile Erasmus Program grant 2014-0848/001-001- Erasmus Mundus Action 2 Partnership ?Critical Skills Learning for Innovation, Sustainable Growth, Mobility and Employability in the Multicultural Environment of the Western Balkans?. The authors would also like to acknowledge the financial support from Funda??o para a Ci?ncia e a Tecnologia (FCT) and Portugal 2020 to the Portuguese Mass Spectrometry Network (Rede Nacional de Espectrometria de Massa RNEM; LISBOA 01 0145 FEDER 402 022125).
Funding Information:
info:eu-repo/grantAgreement/FCT/6817 - DCRRNI ID/UIDP%2F04378%2F2020/PT#
info:eu-repo/grantAgreement/FCT/6817 - DCRRNI ID/UIDB%2F04378%2F2020/PT#
( UID/QUI/50006/2020 ) and the project LA/P/0140/2020 of the Associate Laboratory Institute for Health and Bioeconomy - i4HB . Srdana Kolakovic acknowledges European Commission (Water JPI project 196 in the WaterWorks2014 ERA-NET Co-funded Call) for the “WATINTECH” project grant and Sigma Agile Erasmus Program grant 2014-0848/001-001 - Erasmus Mundus Action 2 Partnership “Critical Skills Learning for Innovation, Sustainable Growth, Mobility and Employability in the Multicultural Environment of the Western Balkans”. The authors would also like to acknowledge the financial support from Fundação para a Ciência e a Tecnologia (FCT) and Portugal 2020 to the Portuguese Mass Spectrometry Network (Rede Nacional de Espectrometria de Massa RNEM; LISBOA 01 0145 FEDER 402 022125).
Publisher Copyright:
© 2021 Elsevier B.V.
PY - 2022/2/1
Y1 - 2022/2/1
N2 - Diclofenac is a pharmaceutical active compound frequently detected in wastewater and water bodies, and often reported to be persistent and difficult to biodegrade. While many previous studies have focussed on assessing diclofenac biodegradation in nitrification and denitrification processes, this study focusses on diclofenac biodegradation in the enhanced biological phosphorus removal (EBPR) process, where the efficiency of this process for diclofenac biodegradation as well as the metabolites generated are not well understood. An enrichment of Accumulibacter polyphosphate accumulating organisms (PAOs) was operated in an SBR for over 300 d, and acclimatized to 20 μg/L of diclofenac, which is in a similar range to that observed in domestic wastewater influents. The diclofenac biotransformation was monitored in four periods of stable operation and linked to the microbial community and metabolic behaviour in each period. Nitrification was observed in two of the four periods despite the addition of a nitrification inhibitor, and these periods were positively correlated with increased diclofenac biodegradation. Interestingly, in two periods with excellent phosphorus removal (>99%) and no nitrification, different levels of diclofenac biotransformation were observed. Period 2, enriched in Accumulibacter Type II achieved more significant diclofenac biotransformation (3.4 μg/gX), while period 4, enriched in Accumulibacter Type I achieved lower diclofenac biotransformation (0.4 μg/gX). In total, 23 transformation products were identified, with lower toxicity than the parent compound, enabling the elucidation of multiple metabolic pathways for diclofenac biotransformation. This study showed that PAOs can contribute to diclofenac biotransformation, yielding less toxic transformation products, and can complement the biodegradation carried out by other organisms in activated sludge, particularly nitrifiers.
AB - Diclofenac is a pharmaceutical active compound frequently detected in wastewater and water bodies, and often reported to be persistent and difficult to biodegrade. While many previous studies have focussed on assessing diclofenac biodegradation in nitrification and denitrification processes, this study focusses on diclofenac biodegradation in the enhanced biological phosphorus removal (EBPR) process, where the efficiency of this process for diclofenac biodegradation as well as the metabolites generated are not well understood. An enrichment of Accumulibacter polyphosphate accumulating organisms (PAOs) was operated in an SBR for over 300 d, and acclimatized to 20 μg/L of diclofenac, which is in a similar range to that observed in domestic wastewater influents. The diclofenac biotransformation was monitored in four periods of stable operation and linked to the microbial community and metabolic behaviour in each period. Nitrification was observed in two of the four periods despite the addition of a nitrification inhibitor, and these periods were positively correlated with increased diclofenac biodegradation. Interestingly, in two periods with excellent phosphorus removal (>99%) and no nitrification, different levels of diclofenac biotransformation were observed. Period 2, enriched in Accumulibacter Type II achieved more significant diclofenac biotransformation (3.4 μg/gX), while period 4, enriched in Accumulibacter Type I achieved lower diclofenac biotransformation (0.4 μg/gX). In total, 23 transformation products were identified, with lower toxicity than the parent compound, enabling the elucidation of multiple metabolic pathways for diclofenac biotransformation. This study showed that PAOs can contribute to diclofenac biotransformation, yielding less toxic transformation products, and can complement the biodegradation carried out by other organisms in activated sludge, particularly nitrifiers.
KW - Biological nutrient removal
KW - Biotransformation
KW - Candidatus Accumulibacter phosphatis
KW - Micropollutants
KW - Pharmaceutical active compounds (PhACs)
UR - http://www.scopus.com/inward/record.url?scp=85118255298&partnerID=8YFLogxK
U2 - 10.1016/j.scitotenv.2021.151232
DO - 10.1016/j.scitotenv.2021.151232
M3 - Article
C2 - 34715209
SN - 0048-9697
VL - 806
JO - Science of the Total Environment
JF - Science of the Total Environment
IS - Pt 3
M1 - 151232
ER -