%0 Journal Article %1 meng2016degradation %A Meng, Lu %A Xi, Jinying %A Yeung, Marvin %D 2016 %J Chemosphere %K 92c40-biochemistry-molecular-biology 92c70-microbiology biofilm %P 248-255 %R 10.1016/j.chemosphere.2015.12.060 %T Degradation of extracellular polymeric substances (EPS) extracted from activated sludge by low-concentration ozonation %U https://www.sciencedirect.com/science/article/pii/S0045653515305142 %V 147 %X Reaction mechanisms between ozone and extracellular polymeric substances (EPS) can be the key of understanding the improvements in microbial aggregates properties by low-concentration ozonation. In this study, EPS are extracted from activated sludge and treated continuously by ozone gas at 270 ± 41 ppm. The reaction between ozone and EPS was investigated by observation of EPS component concentrations, functional groups and molecular weight distributions using UV–Vis spectrometry, excitation-emission matrix fluorescence spectroscopy (EEM), high performance size-exclusion chromatography (HPSEC) and gas chromatography-mass spectrometry (GC–MS). In a 12-hour-ozonation experiment, significant ozone consumption was observed in the first 4 h and protein concentration in EPS solution was reduced by 30 ± 12%. However, the polysaccharides concentration only had a slightly decrease at the end of the ozonation process. UV–Vis spectra and EEM spectra results suggest that ozone removed protein and fluorescent matters (SMP and tryptophan-like aromatic protein) rapidly by attacking specific amino acid residues on polypeptide chain. After ozonation, the molecular weight of polysaccharide and protein dropped by 4 orders of magnitude according to HPSEC results. TOC concentration of EPS solution was reduced by 13 ± 2% after ozonation. The loss in TOC could be explained by the observation of volatile organic compounds such as carboxylic acids, aldehydes and ketones in the off-gas detected by GC–MS. The results in this study can provide a better understanding towards the mechanisms of improvements in activated sludge properties by ozonation.

@article{meng2016degradation, abstract = {Reaction mechanisms between ozone and extracellular polymeric substances (EPS) can be the key of understanding the improvements in microbial aggregates properties by low-concentration ozonation. In this study, EPS are extracted from activated sludge and treated continuously by ozone gas at 270 ± 41 ppm. The reaction between ozone and EPS was investigated by observation of EPS component concentrations, functional groups and molecular weight distributions using UV–Vis spectrometry, excitation-emission matrix fluorescence spectroscopy (EEM), high performance size-exclusion chromatography (HPSEC) and gas chromatography-mass spectrometry (GC–MS). In a 12-hour-ozonation experiment, significant ozone consumption was observed in the first 4 h and protein concentration in EPS solution was reduced by 30 ± 12%. However, the polysaccharides concentration only had a slightly decrease at the end of the ozonation process. UV–Vis spectra and EEM spectra results suggest that ozone removed protein and fluorescent matters (SMP and tryptophan-like aromatic protein) rapidly by attacking specific amino acid residues on polypeptide chain. After ozonation, the molecular weight of polysaccharide and protein dropped by 4 orders of magnitude according to HPSEC results. TOC concentration of EPS solution was reduced by 13 ± 2% after ozonation. The loss in TOC could be explained by the observation of volatile organic compounds such as carboxylic acids, aldehydes and ketones in the off-gas detected by GC–MS. The results in this study can provide a better understanding towards the mechanisms of improvements in activated sludge properties by ozonation.}, added-at = {2024-02-02T04:25:58.000+0100}, author = {Meng, Lu and Xi, Jinying and Yeung, Marvin}, biburl = {https://www.bibsonomy.org/bibtex/294195009ff1e3a5a513c057139ce7d75/gdmcbain}, doi = {10.1016/j.chemosphere.2015.12.060}, interhash = {081d479c0dbe4a3e6db37173a52812ed}, intrahash = {94195009ff1e3a5a513c057139ce7d75}, issn = {0045-6535}, journal = {Chemosphere}, keywords = {92c40-biochemistry-molecular-biology 92c70-microbiology biofilm}, pages = {248-255}, timestamp = {2024-02-02T04:25:58.000+0100}, title = {Degradation of extracellular polymeric substances (EPS) extracted from activated sludge by low-concentration ozonation}, url = {https://www.sciencedirect.com/science/article/pii/S0045653515305142}, volume = 147, year = 2016 }