Optimization for extracellular polymeric substances extraction of microbial aggregates

2015 ◽  
Vol 71 (7) ◽  
pp. 1106-1112 ◽  
Author(s):  
Liang Zhu ◽  
Haitian Yu ◽  
Yimei Liu ◽  
Hanying Qi ◽  
Xiangyang Xu
Keyword(s):  
Humic Acid ◽  
Extracellular Polymeric Substances ◽  
Three Dimensional ◽  
Interaction Mechanism ◽  
Extraction Methods ◽  
Aerobic Granules ◽  
Excitation Emission Matrix ◽  
Cation Exchange Resins ◽  
Heat Method ◽  
Exchange Resins

The extracellular polymeric substances (EPS) are important macromolecular components in microbial aggregates. The three EPS extraction methods – ultrasound + cation exchange resins (CER) + sulfide, ultrasound + formamide + NaOH, and ultrasound + heat – were investigated in the study, and the component differences of extracted EPS from the loose flocs and dense aerobic granules were compared using chemical analysis and three-dimensional excitation-emission matrix (3D-EEM). Results showed that the contents of EPS were extracted effectively by ultrasound + formamide + NaOH and ultrasound + heat methods, and the ultrasound + CER + sulfide method did not extract the polysaccharides (PS) or protein (PN) contents from the sludge samples. The 3D-EEM analysis indicated that the nature of peak B/D, peak C/E/F, and peak A/G were attributed to PN-like, humic acid-like and fulvic acid-like fluorophores. All fluorophores can be detected from the EPS extracted through the ultrasound + heat method. Hopefully this will provide more information about the EPS interaction mechanism of microbial aggregates.

Three-dimensional excitation emission matrix fluorescence spectroscopy and gel-permeating chromatography to characterize extracellular polymeric substances in aerobic granulation

2010 ◽  
Vol 61 (11) ◽  
pp. 2931-2942 ◽  
Author(s):  
Huacheng Xu ◽  
Pinjing He ◽  
Guanzhao Wang ◽  
Liming Shao
Keyword(s):  
Molecular Weight ◽  
Fluorescence Spectroscopy ◽  
Extracellular Polymeric Substances ◽  
Operating Time ◽  
Three Dimensional ◽  
Aerobic Granules ◽  
Aerobic Granulation ◽  
Excitation Emission Matrix ◽  
Two Peaks ◽  
Eem Fluorescence

Three-dimensional excitation emission matrix (EEM) fluorescence spectroscopy and gel-permeating chromatography (GPC) were employed to characterize the extracellular polymeric substances (EPS) in aerobic granulation. EPS matrix in this study was stratified into four fractions: (1) supernatant, (2) slime, (3) loosely bound EPS (LB-EPS), and (4) tightly bound EPS (TB-EPS). The results showed that the dissolved organic carbon was mainly distributed in TB-EPS fraction, and increased with increasing the operating time. The supernatant, slime, and LB-EPS fractions exhibited four fluorescence peaks, an autochthonous signature, unimodal MW distribution and lower molecular weight (MW) (3 < log [MW]<5), whereas the TB-EPS fraction only had two peaks, an allochthonous signature, multiple peaks and higher MW (5 < log [MW]<7). It was deemed that the formation of aerobic granules was correlated with the accumulation of proteins in the TB-EPS fraction. EEM spectroscopy and GPC profiles could be used as appropriate and effective methods to characterize the EPS in aerobic granulation from a micro-view level.

3DEEM spectroscopy analysis to assess the EPS composition in different carriers in HMBR systems

2016 ◽  
Vol 74 (11) ◽  
pp. 2708-2716 ◽  
Author(s):  
Meixiang Sun ◽  
Man Wu ◽  
Wen Liu ◽  
Huiying Liu ◽  
Yezhong Zhang ◽  
...  
Keyword(s):  
Humic Acid ◽  
Fulvic Acid ◽  
Membrane Fouling ◽  
Fluorescence Spectra ◽  
Membrane Bioreactor ◽  
Extracellular Polymeric Substances ◽  
Three Dimensional ◽  
Spectroscopy Analysis ◽  
Excitation Emission Matrix ◽  
Parallel Factor

A hybrid membrane bioreactor (HMBR) with biological band carriers (Reactor A) and an HMBR with suspended honeycomb carriers (Reactor B) were conducted in parallel to investigate the effects of different carriers on extracellular polymeric substances (EPS). Composition and concentration of EPS were examined by three-dimensional excitation-emission matrix (3DEEM) fluorescence spectra and parallel factor analysis (PARAFAC). 3DEEM spectra demonstrated that the main organic substances of the EPS in two reactors were protein-like, humic acid-like and fulvic acid-like substances. The fluorescence intensity (FI) indicated that the protein-like composition was dominant in EPS, and its intensity in reactor B was stronger than that in A (392.94 > 250.25). Results of the FI identified from the 3DEEM by PARAFAC showed that the EPS in two reactors included two humic acid-like compositions C1 (230, 320/406 nm), C2 (250, 360/440 nm) and one protein-like C4 (230, 280/340 nm), while C3 was fulvic acid-like (220/429 nm) and protein-like (230/357 nm) in reactor A and B, respectively. The proportion and FI of protein-like substances in reactor B were higher than that in A. Consequently, it was concluded that reactor A could control the membrane fouling effectively, compared with reactor B.

scholarly journals Variations of sludge characteristics during the advanced anaerobic digestion process and the dewaterability of the treated sludge conditioning with PFS, PDMDAAC and synthesized PFS-PDMDAAC

2018 ◽  
Vol 78 (5) ◽  
pp. 1189-1198 ◽  
Author(s):  
Jinghui Zhang ◽  
Hong Yang ◽  
Wei Li ◽  
Yang Wen ◽  
Xingmin Fu ◽  
...  
Keyword(s):  
Particle Size ◽  
Anaerobic Digestion ◽  
Extracellular Polymeric Substances ◽  
Three Dimensional ◽  
Sludge Treatment ◽  
Capillary Suction ◽  
Excitation Emission Matrix ◽  
Digestion Process ◽  
Sludge Dewaterability ◽  
Polyferric Sulfate

Abstract Anaerobic digestion with thermal hydrolysis pretreatment (THP), also called advanced anaerobic digestion (AAD), is a mainstream technology for sludge treatment. AAD changes sludge, it can degrade extracellular polymeric substances (EPS), release EPS from the sludge, and alter the particle size distribution. We synthesized PFS–PDMDAAC from the inorganic coagulant polyferric sulfate (PFS) and the organic coagulant polymer polydimethyldiallylammonium chloride (PDMDAAC) in various PFS:PDMDAAC weight ratios. We investigated the effects of PFS–PDMDAAC pretreatment on AAD sludge dewaterability, and developed an explanation for them. Capillary suction time (CST) was used as a measure of sludge dewaterability. Dissolved organic matter, the three-dimensional excitation emission matrix, particle size (d0.5), zeta potential, and sludge microstructure were observed in order to explain changes in sludge dewaterability that resulted from different compositions and dosages of coagulants. Treatment with PFS alone gave no significant improvement in sludge dewaterability. PDMDAAC used alone greatly improved sludge dewaterability. Synthesized PFS–PDMDAAC which had a relatively high proportion of PDMDAAC by weight performed similarly to PDMDAAC. PFS–PDMDAAC synthesized in the ratio (PDF:PDMDAAC) 1:5 by weight provided good dewaterability. The dosage can be reduced by 16.7% of the dosage for conditioning by PDMDAAC alone.

Effective methods for extracting extracellular polymeric substances from Shewanella oneidensis MR-1

2016 ◽  
Vol 74 (12) ◽  
pp. 2987-2996 ◽  
Author(s):  
You-Fen Dai ◽  
Yong Xiao ◽  
En-Hua Zhang ◽  
Li-Dan Liu ◽  
Ling Qiu ◽  
...  
Keyword(s):  
Extracellular Polymeric Substances ◽  
Ethylenediaminetetraacetic Acid ◽  
Heating Temperature ◽  
Three Dimensional ◽  
Shewanella Oneidensis ◽  
Cell Lysis ◽  
Extraction Methods ◽  
Bacterial Cells ◽  
Matrix Spectrum ◽  
Dry Cell

Extracellular polymeric substances (EPS) play crucial roles in bio-aggregate formation and survival of bacterial cells. To develop an effective but harmless method for EPS extraction from Shewanella oneidensis MR-1, five extraction methods, i.e. centrifugation (control), heating (40, 45, 50, and 60 °C), and treatments with H2SO4, ethylenediaminetetraacetic acid (EDTA) and NaOH, were examined, respectively. Results from scanning electron microscope and flow cytometric analyses indicate that MR-1 cells were severely broken by H2SO4, NaOH and heating temperature ≥45 °C. Proteins and polysaccharides in EPS extracted by heating at 40 °C were 7.12 and 1.60 mg g−1 dry cell, respectively. Although EDTA treatment had a relatively lower yield of EPS (proteins and polysaccharides yields of 5.15 and 1.30 mg g−1 dry cell, respectively), cell lysis was barely found after EPS extraction. Three peaks were identified from the three-dimensional excitation–emission matrix spectrum of each EPS sample, suggesting the presence of protein-like substances. Furthermore, the peak intensity was in good accordance with protein concentration measured by the chemical analysis. In short, heating (40 °C) and EDTA treatments were found the most suitable methods for EPS extraction considering the cell lysis and EPS content, composition and functional groups together.

Characterization of dissolved organic matter (DOM) extracted from soils by hot water percolation (HWP)

2010 ◽  
Vol 59 (1) ◽  
pp. 99-108 ◽  
Author(s):  
M. Takács ◽  
Gy. Füleky
Keyword(s):  
Organic Matter ◽  
Humic Acid ◽  
Natural Organic Matter ◽  
Extraction Methods ◽  
Soil Samples ◽  
Hot Water ◽  
Soil Extracts ◽  
Water Percolation ◽  
Soil Humic Acid

The Hot Water Percolation (HWP) technique for preparing soil extracts has several advantages: it is easily carried out, fast, and several parameters can be measured from the same solution. The object of this study was to examine the possible use of HWP extracts for the characterization of soil organic matter. The HPLC-SEC chromatograms, UV-VIS and fluorescence properties of the HWP extracts were studied and the results were compared with those of the International Humic Substances Society (IHSS) Soil Humic Acid (HA), IHSS Soil Fulvic Acid (FA) and IHSS Suwannee Natural Organic Matter (NOM) standards as well as their HA counterparts isolated by traditional extraction methods from the original soil samples. The DOM of the HWP solution is probably a mixture of organic materials, which have some characteristics similar to the Soil FA fractions and NOM. The HWP extracted organic material can be studied and characterized using simple techniques, like UV-VIS and fluorescence spectroscopy.

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