Carbon source type can affect tetracycline removal by Pseudomonas sp. TC952 through regulation of extracellular polymeric substances composition and production

Extracellular polymeric substances—antibiotics interaction in activated sludge: A review

“…2 EPS synthesis and regulation under different antibiotics exposure via QS, reprinted with permission from Ref. [ 49 ]; copyright (2022) Elsevier. …”

“…For example, the percentage of protein in heterotrophic sludge was much higher than that of polysaccharides, whereas autotrophic sludge exhibited a converse trend [ 100 ]. Reportedly, the abundant existence of carbohydrate-related substrates would be beneficial for the synthesis of polysaccharides in sludge EPS [ 101 , 102 ], while protein content increased with the presence of peptone and serine-related substances (protein-like) [ 49 ]. Additionally, sludge fed with starch has a higher polysaccharide content in EPS than sludge fed with glucose [ 103 ].…”

“…[ 100 ] observed that sludge fed with easily biodegradable substrates would generate more protein in EPS, restraining humic acid production. Undoubtedly, the obvious variation in the sludge EPS composition would affect the distribution of the functional groups and adsorption regions (hydrocarbons, proteins, polysaccharides, and nucleic acids) and finally lead to different antibiotics removal efficiencies [ 49 ].…”

“…TC952. Langmuir model First-order kinetic model Tyrosine and tryptophan Hydrophobic interaction −1.30 3.3, 7.7, 9.7 [ 49 ] Oxytetracycline C 22 H 24 N 2 O 9 M.W = 460.4 g mol −1 Sludge Langmuir model Pseudo-second-order model – – −1.12 3.2, 7.5, 8.9 [ 108 ] Chlortetracycline C 22 H 23 ClN 2 O 8 M.W = 478.9 g mol −1 Sludge Langmuir model Pseudo-second-order model – – −0.62 3.3, 7.6, 9.3 [ 108 ] Trimethoprim (TMP) C 14 H 18 N 4 O 3 M.W = 290.3 g mol −1 Activated sludge – Pseudo-second-order kinetic model. Tyrosine and tryptophan – 0.91 3.23, 6.76 [ 96 ] Ciprofloxacin (CIP) C 17 H 18 FN 3 O 3 M.W = 331.3 g mol −1 Secondary-treated sludge Langmuir model Pseudo-first-order kinetic equation – – 0.28 6.16, 8...…”

“…Previous studies reported that ARGs could be adsorbed onto sludge EPS and form a stable EPS-ARGs complex [ 76 ], and the absolute abundance of EPS-associated ARGs reached 1.49 × 10 7 –4.45 × 10 9 copies per g VSS in sludge [ 77 ]. However, the ARGs adsorbed on sludge EPS would be partially released due to the variation of the environmental conditions [ 49 ]. Considering that most EPS-associated ARGs are contained in sewage sludge after dewatered treatment, the destruction of the EPS-ARGs complex may cause a secondary release of ARGs into the environment from sewage sludge.…”