title: Effects of CeO₂ nanoparticles on production and physicochemical characteristics of extracellular polymeric substances in biofilms in sequencing batch biofilm reactor.
abstract: Extracellular polymeric substances (EPS) are a major component of biofilms that act as a gel-like matrix, binding the cells together to form their three-dimensional structure. The effects of ceria nanoparticles (CeO2 NPs) on the production and physicochemical characteristics of EPS in biofilms in a sequencing batch biofilm reactor were investigated. Total EPS production, including loosely bound EPS (LB-EPS) and tightly bound EPS (TB-EPS), increased by 35.41% compared to in control tests without CeO2 NPs. Protein production increased by 47.02% (LB-EPS) and 58.83% (TB-EPS) after 50 mg/L CeO2 NP exposure. Three-dimensional excitation-emission fluorescence spectra revealed that tyrosine (LB-EPS) and aromatic (TB-EPS) protein-like substances formed after CeO2 NP exposure. Fourier transform infrared spectroscopy results indicated the susceptibility of -OH and -NH2 in EPS hydroxyl and amine groups to CeO2 NPs. Exposure to 50 mg/L CeO2 NPs reduced the flocculating capacity of LB-EPS (51.78%) and TB-EPS (17.14%), consistent with the decreased zeta potential.
authors.affiliation: Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098, People's Republic of China; College of Environment, Hohai University, Nanjing 210098, People's Republic of China.
authors.forename: Guoxiang
authors.initials: G
authors.lastname: You
authors.affiliation: Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098, People's Republic of China; College of Environment, Hohai University, Nanjing 210098, People's Republic of China. Electronic address: hhuhjyhj@126.com.
authors.forename: Jun
authors.initials: J
authors.lastname: Hou
authors.affiliation: Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098, People's Republic of China; College of Environment, Hohai University, Nanjing 210098, People's Republic of China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Xu
authors.affiliation: Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098, People's Republic of China; College of Environment, Hohai University, Nanjing 210098, People's Republic of China.
authors.forename: Chao
authors.initials: C
authors.lastname: Wang
authors.affiliation: Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098, People's Republic of China; College of Environment, Hohai University, Nanjing 210098, People's Republic of China.
authors.forename: Peifang
authors.initials: P
authors.lastname: Wang
authors.affiliation: Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098, People's Republic of China; College of Environment, Hohai University, Nanjing 210098, People's Republic of China. Electronic address: mlz1988@126.com.
authors.forename: Lingzhan
authors.initials: L
authors.lastname: Miao
authors.affiliation: Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098, People's Republic of China; College of Environment, Hohai University, Nanjing 210098, People's Republic of China.
authors.forename: Yanhui
authors.initials: Y
authors.lastname: Ao
authors.affiliation: Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098, People's Republic of China; College of Environment, Hohai University, Nanjing 210098, People's Republic of China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Li
authors.affiliation: Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098, People's Republic of China; College of Environment, Hohai University, Nanjing 210098, People's Republic of China.
authors.forename: Bowen
authors.initials: B
authors.lastname: Lv
mesh_terms: D018441:Biofilms; D001704:Biopolymers / Q000096:biosynthesis*; D019149:Bioreactors / Q000382:microbiology*; D002563:Cerium / Q000737:chemistry*; D005109:Extracellular Matrix / Q000378:metabolism; D005427:Flocculation; D053758:Nanoparticles / Q000737:chemistry*; D011506:Proteins / Q000378:metabolism; D017550:Spectroscopy, Fourier Transform Infrared; D014865:Waste Disposal, Fluid / Q000379:methods
chemical_list: D001704:Biopolymers; D011506:Proteins; D002563:Cerium; C030583:ceric oxide
keywords: CeO(2) nanoparticle; Extracellular polymeric substances (EPS); Physicochemical characteristics; Production; Sequencing batch biofilm reactor (SBBR)