title: Changes of the reactor performance and the properties of granular sludge under tetracycline (TC) stress.
abstract: In this study, the response of nitrifying granules (NG) and conventional granules (CG) to tetracycline (TC) was compared. The presence of TC made granules break down into small fractions and led to nitrite accumulation in nitrifying system; while it had little toxic effect on CG system. Specific oxygen uptake rate tests showed 3.3% inhibition of ammonium oxidizing bacteria and 25.7% inhibition of nitrite oxidizing bacteria in the NG system. Granules produced more extracellular polymeric substances (EPS) to protect themselves from the TC stress, with higher production of proteins compared to polysaccharides. FTIR data also revealed significant changes of protein functional groups, while only small changes in polysaccharides functional groups were found. Three dimensional excitation-emission matrix fluorescence spectroscopy showed a decrease of peak intensity, indicating quenching effect of TC on EPS fluorescence, and also a blue shift of peak position, indicating chemical changes of EPS components.
authors: Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Jinan 250100, China.
authors: Yijing
authors: Y
authors: Shi
authors: Sufang
authors: S
authors: Xing
authors: Xinhua
authors: X
authors: Wang
authors: Shuguang
authors: S
authors: Wang
mesh_terms: D001419:Bacteria / Q000187:drug effects; D001704:Biopolymers / Q000032:analysis; D019149:Bioreactors / Q000382:microbiology*; D008826:Microbial Sensitivity Tests; D010316:Particle Size; D012722:Sewage / Q000382:microbiology*; D013050:Spectrometry, Fluorescence; D017550:Spectroscopy, Fourier Transform Infrared; D055672:Static Electricity; D013312:Stress, Physiological / Q000187:drug effects*; D013752:Tetracycline / Q000737:chemistry / Q000494:pharmacology*; D013997:Time Factors; D060753:Water Quality
chemical_list: D001704:Biopolymers; D012722:Sewage; D013752:Tetracycline