Characterization of extracellular polymeric substances produced by mixed microorganisms in activated sludge with gel-permeating chromatography, excitation-emission matrix fluorescence spectroscopy measurement and kinetic modeling.
In this work the extracellular polymeric substances (EPS) produced by mixed microbial community in activated sludge are characterized using gel-permeating chromatography (GPC), 3-dimensional excitation-emission matrix (EEM) fluorescence spectroscopy measurement and mathematical modeling. Chromatograms of extracted EPS exhibit seven peaks, among which proteins have four peaks and polysaccharides have three peaks. Evolution of the chromatogram area indicates that the quantity of produced EPS increases significantly in the substrate utilization process. With the parallel factor analysis (PARAFAC) approach, two components of the polymer matrix are identified by the EEM analysis, one as EPS proteins at Ex/Em 280/340 nm and one matrix associated as fulvic-acid-like substances at 320/400 nm. The proteins and fulvic-acid-like substances in the EPS increase in the substrate utilization phase, but decrease in the endogenous phase. To have a better insight into EPS production, the kinetic modeling of EPS is performed with regard to their molecular weight distribution and chemical natures identified by GPC and EEM. In this way, the dynamics of these important microbial products are better understood.
Ni
Bing-Jie
BJ
Department of Chemistry, University of Science and Technology of China, Hefei 230026, China.
Fang
Fang
F
Xie
Wen-Ming
WM
Sun
Min
M
Sheng
Guo-Ping
GP
Li
Wei-Hua
WH
Yu
Han-Qing
HQ
D001419:Bacteria / Q000378:metabolism*; D001578:Benzopyrans / Q000378:metabolism; D001704:Biopolymers / Q000378:metabolism*; D002138:Calibration; D002850:Chromatography, Gel; D005110:Extracellular Space / Q000378:metabolism*; D007700:Kinetics; D008954:Models, Biological; D008970:Molecular Weight; D012722:Sewage / Q000382:microbiology*; D013050:Spectrometry, Fluorescence; D013997:Time Factors
D001578:Benzopyrans; D001704:Biopolymers; D012722:Sewage; C005023:fulvic acid