TY - JOUR
T1 - Eat seldom is better than eat frequently
T2 - Pharmaceuticals degradation kinetics, enantiomeric profiling and microorganisms in moving bed biofilm reactors are affected by feast famine cycle times
AU - Liang, Chuanzhou
AU - Svendsen, Sif B.
AU - de Jonge, Nadieh
AU - Carvalho, Pedro N.
AU - Nielsen, Jeppe Lund
AU - Bester, Kai
N1 - Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.
PY - 2024/4/15
Y1 - 2024/4/15
N2 - Feast-famine (FF) regimes improved the removal of recalcitrant pharmaceuticals in moving bed biofilm reactors (MBBRs), but the optimal FF cycle remained unresolved. The effects of FF cycle time on the removal of bulk substrates (organic carbon and nitrogen) and trace pharmaceuticals by MBBR are systematically evaluated in this study. The feast to famine ratio was fixed to 1:2 to keep the same loading rate, but the time for the FF cycles varied from 18 h to 288 h. The MBBR adapted to the longest FF cycle time (288 h equaling 48 × HRT) resulted in significantly higher degradation rates (up to +183%) for 12 out of 28 pharmaceuticals than a continuously fed (non-FF) reactor. However, other FF cycle times (18, 36, 72 and 144 h) only showed a significant up-regulation for 2–3 pharmaceuticals compared to the non-FF reactor. Enantioselective degradation of metoprolol and propranolol occurred in the second phase of a two phase degradation, which was different for the longer FF cycle time. N-oxidation and N-demethylation pathways of tramadol and venlafaxine differed across the FF cycle time suggestin the FF cycle time varied the predominant transformation pathways of pharmaceuticals. The abundance of bacteria in the biofilms varied considerably between different FF cycle times, which possibly caused the biofilm to remove more recalcitrant bulk organic C and pharmaceuticals under long cycle times.
AB - Feast-famine (FF) regimes improved the removal of recalcitrant pharmaceuticals in moving bed biofilm reactors (MBBRs), but the optimal FF cycle remained unresolved. The effects of FF cycle time on the removal of bulk substrates (organic carbon and nitrogen) and trace pharmaceuticals by MBBR are systematically evaluated in this study. The feast to famine ratio was fixed to 1:2 to keep the same loading rate, but the time for the FF cycles varied from 18 h to 288 h. The MBBR adapted to the longest FF cycle time (288 h equaling 48 × HRT) resulted in significantly higher degradation rates (up to +183%) for 12 out of 28 pharmaceuticals than a continuously fed (non-FF) reactor. However, other FF cycle times (18, 36, 72 and 144 h) only showed a significant up-regulation for 2–3 pharmaceuticals compared to the non-FF reactor. Enantioselective degradation of metoprolol and propranolol occurred in the second phase of a two phase degradation, which was different for the longer FF cycle time. N-oxidation and N-demethylation pathways of tramadol and venlafaxine differed across the FF cycle time suggestin the FF cycle time varied the predominant transformation pathways of pharmaceuticals. The abundance of bacteria in the biofilms varied considerably between different FF cycle times, which possibly caused the biofilm to remove more recalcitrant bulk organic C and pharmaceuticals under long cycle times.
KW - Chiral separations
KW - Co-metabolism
KW - Enantioselective degradation
KW - Microbial community
KW - Organic micropollutants
UR - http://www.scopus.com/inward/record.url?scp=85185835813&partnerID=8YFLogxK
U2 - 10.1016/j.jhazmat.2024.133739
DO - 10.1016/j.jhazmat.2024.133739
M3 - Journal article
C2 - 38401210
AN - SCOPUS:85185835813
SN - 0304-3894
VL - 468
JO - Journal of Hazardous Materials
JF - Journal of Hazardous Materials
M1 - 133739
ER -