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1

The performance of extracellular polymeric substance (EPS) on stability of Aerobic granular sludge (AGS)

Na Hamiruddin, Na Awang, Mg Shaaban

Civil and Environmental Engineering Reports

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2019

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Vol. 29, no. 3

60--69

EN

Various article which indicating the Aerobic granular sludge (AGS) instability, particularly in prolonged phase operating duration become a significant obstacle to its implementation. Generally, prolonged the operation period will lost its stability that can degrade performance effectiveness. As AGS stabilization in hydrodynamic shear force and resisting mass transfer resistance within the reactor generally defined or evaluated by microbial community, bioactivity, extracellular polymeric substance (EPS) structure and granular aspect. The aim of this research in order to illustrate the EPS formation on AGS which is preserved at 4°C in sequencing batch reactor (SBR) by sewage for eight months. The effective of granulation method and redevelopment of AGS stability by particular pressure produced with several hydrodynamic shear force and mass transfer resistance which controlled by low organic loading rate (OLR) between 0.26 and 0.81 kg CODs/m³ d with 1.33 cm/s of superficial air velocity (SAV). The confocal laser scanning microscope (CLSM), Fourier transform infrared (FTIR), and energy dispersive X-ray spectrometer (EDX) were implemented to notice the evolution in composition of EPS that revealed the intermolecular interaction helped the aerobic granule stability as seed to achieved the performance of EPS on stability of AGS.

2

Antibiofilm and antifouling activities of extracellular polymeric substances isolated from the bacteria associated with marine gastropod Turbo sp.

Viju N., Satheesh S., Punitha S. M. J.

Oceanological and Hydrobiological Studies

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2016

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Vol. 45, No. 1

11--19

EN

The extracellular polymeric substances (EPS) produced by the bacteria associated with the gastropod Turbo sp. were isolated and screened for antibacterial activity against biofilm-forming bacteria. EPS of five out of 13 strains showed inhibitory activities in the antibacterial assay. Furthermore, the antibiofilm and antifouling activity of the most active EPS isolated from the strain KT1 was studied using various in vitro and in vivo bioassays. Results revealed that EPS significantly inhibited the growth and biofilm formation of bacteria. Furthermore, the antifouling coating developed with bacterial EPS considerably reduced the recruitment of fouling organisms on coated surfaces submerged in the seawater. The functional groups present in EPS, characterized by strong activity,were analyzed using FT-IR and the spectrum showed the presence of alcohol, amines, carboxylic acid and esters. The bacterium responsible for the production of bioactive EPS was identified as Pseudomonas aeruginosa, using the 16S rRNA gene. Since the findings of this study revealed the antibiofilm and antifouling activities of EPS, further long term field tests and characterization of the bioactive compound of the EPS could lead to the development of eco-friendly antifouling coating.

3

Biosorption of Pb(II) and Zn(II) by Extracellular Polymeric Substance (Eps) of Rhizobium Radiobacter : Equilibrium, Kinetics and Reuse Studies

Wang L., Yang J., Chen Z., Liu X., Ma F.

Archives of Environmental Protection

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2013

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Vol. 39, no. 2

129--140

EN

The extracellular polymeric substance (EPS) produced from Rhizobium radiobacter F2, designated as EPSF2 , was investigated as a biosorbent for the removal of Pb(II) and Zn(II) from aqueous solution. The optimum biosorption pH values were 5.0 for Pb(II) and 6.0 for Zn(II). Kinetics study revealed that the biosorption followed pseudo-first-order model well, and the equilibrium data fit the Langmuir model better. The adsorbed metal ions could be effectively desorbed by HCl. Desrobed EPSF2 regained 80% of the initial biosorption capacity after five cycles of biosorption-desorption-elution. These results demonstrated that EPSF2 could be a promising alternative for Pb(II) and Zn(II) removal from aqueous solution.

4

Exposure to chlorine affects the extracellular polymeric substance production and cell surface hydrophobicity in biofilm bacteria

Rathi R., Satheesh S.

Oceanological and Hydrobiological Studies

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2012

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Vol. 41, No. 4

17-24

EN

Chlorination is a common antifouling method adopted by industrial units to minimize the fouling growth on cooling systems. In the present study, the effect of sodium hypochlorite on extracellular polymeric substance (EPS) production, hydrophobicity, cell adhesion and viability of marine bacteria involved in biofilm formation were assessed in laboratory condition. Two bacterial strains, tentatively identified as Alteromonas sp. and Pseudomonas sp. isolated from the surface of seaweeds were used as test organisms for the present study. The bacterial cultures were treated with sodium hypochlorite at 25% of the minimum inhibitory concentration. Results showed considerable variation in the production of EPS, viable counts, hydrophobicity and adhesion ability of bacteria treated with sodium hypochlorite. In general, the present study indicated that chlorination affects some important characteristics involved in the biofilm formation and thereby reduces the adhesion rate on surfaces.

5

Distribution of extracellular polymeric substances and their role in aerobic granule formation

Miksch K., Kończak B.

Chemical and Process Engineering

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2012

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Vol. 33, nr 4

679--688

EN

This study investigated the quantity and distribution of extracellular polymeric substances (EPS) in aerobic granules. Results showed that EPS play an important role in the formation and stabilisation of granules. The content of EPS significantly increases during the first weeks of biogranulation. An analysis of EPS in the granules revealed that the protein level was 5 times higher than in polysaccharides. The increase of protein content correlated with the growth of cell hydrophobicity (r2 = 0.95). EPS and hydrophobicity are important factors in cell adhesion and formation of granules. The aim of this work was also to determine the distribution of EPS in the granule structure. In situ EPS staining showed that EPS are located mostly in the center of granules and in the subsurface layer. The major components of the EPE matrix are proteins, nucleic acids and [beta]-polysaccharides. These observations confirm the chemical extraction data and indicate that granule formation and stability are dependent on protein content.

6

Analiza zjawiska biofilmu - warunki jego powstawania i funkcjonowania

Kołwzan B.

Ochrona Środowiska

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2011

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Vol. 33, nr 4

3-14

PL

Adhezja komórek bakteryjnych do różnego typu powierzchni możliwa jest dzięki wytwarzanym przez mikroorganizmy polimerom zewnątrzkomórkowym oraz takim strukturom, jak fimbrie i rzęski. Dojrzała postać biofilmu składa się z wielu mikrokolonii, a komórki mikroorganizmów połączone są ze sobą zewnątrzkomórkową substancją polimeryczną (EPS). W skład EPS wchodzą polisacharydy, białka, kwasy nukleinowe, surfaktanty, lipidy oraz woda. Komórki wewnątrz biofilmu charakteryzują się specjalizacją do pełnienia różnych funkcji i wykazują cechy odmienne niż komórki żyjące w postaci wolnej. Konstrukcja i organizacja tych skupisk chroni mikroorganizmy przed niekorzystnym wpływem czynników zewnętrznych. Prawidłowe funkcjonowanie wytworzonego biofilmu zapewnia sygnalizacja międzykomórkowa (quorum sensing), oparta na cząsteczkach sygnałowych, które swobodnie dyfundują z jednej komórki do drugiej. Biofilm występuje powszechnie i bierze aktywny udział w wielu ważnych procesach mikrobiologicznych zachodzących w przyrodzie. Powoduje też poważne straty w gospodarce oraz ułatwia rozprzestrzenianie się trudnych do leczenia zakażeń medycznych. Zasiedlanie sieci wodociągowej przez biofilm stanowi zagrożenie sanitarne konsumentów wody. Poznanie struktury, mechanizmu powstawania oraz funkcjonowania biofilmu jest niezbędne do poprawy skuteczności prowadzonych przy jego udziale procesów technologicznych, a także do opracowania nowych, skutecznych metod jego zwalczania.

EN

Adhesion of bacterial cells to a diversity of surfaces is attributable primarily to the extracellular polymers produced by some microorganisms, and, additionaly, to such structures as fimbria and cilia. A mature biofilm is composed of many different microcolonies, where microbial cells are integrated with each other by an extracellular polymeric substance (EPS). An EPS consists of polysaccharides, proteins, nucleic acids, surfactants, lipids and water. The cells in the biofilm interior are highly specialized forms capable of fulfilling a variety of functions, and their properties differ noticeably from those of the free cells. The structure and organization of these specialized microbial clusters protect them against adverse external influences. Proper functioning of the biofilm is guaranteed by quorum sensing via signaling molecules that freely diffuse from one bacterium to another. Being active participants in various microbiological processes, biofilms have now become commonplace. They are largely to blame for heavy losses in a country's economy, and for the potential to spread infections that are difficult to treat. The colonization of a water-pipe network by a biofilm carries serious risk to public health. In conclusion, good knowledge of the biofilm structure, as well as the proper understanding of the mechanisms underlying the formation and functioning of a biofilm, is a requisite not only for upgrading the efficiency of a technological process conducted in the presence of a biofilm, but also for developing new and effective methods of biofilm degradation.

7

Extracellular polymeric substances in the nitrifying activated sludge

Raszka A., Surmacz-Górska J., Żabczyński S.

Architecture Civil Engineering Environment

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2010

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Vol. 3, no. 3

115-119

EN

The aim of the study was to find out the amount and composition of extracellular polymeric substances (EPS) produced by activated sludge bacteria during nitrification of high ammonia concentrations. Treatment of synthetic leachate-imitated and real landfill leachate wastewater was performed in seven lab-scale membrane bioreactors during approx. 9 months and at different sludge age. Proteins, saccharides, humic substances were measured in an activated sludge extract. The obtained results showed that proportions of analyzed constituents were approximate in synthetically loaded reactors: proteins 40-65%, saccharides 26-45% and humic substances 7-17%, while in real leachate loaded reactor the main constituent were saccharides (50-62%) and the rest was divided equally between proteins and humus. The total EPS production (sum of proteins, saccharides and humic substances) seems to be dependent mostly on ammonia load, but a stress originated from toxic wastewater constituents or short sludge age can also have influence on final EPS concentration.

PL

Celem pracy było określenie ilości i składu substancji zewnątrzkomórkowych (ang. extracellular polymeric substances, EPS) produkowanych przez bakterie osadu czynnego podczas nitryfikacji wysokich stężeń azotu amonowego. Proces oczyszczania ścieków syntetycznych oraz rzeczywistych imitujących odcieki wysypiskowe prowadzono w siedmiu bioreaktorach membranowych przez okres ok. 9 miesięcy metodą osadu czynnego przy różnych wiekach osadu. W ekstrakcie osadu czynnego oznaczano białka, cukry oraz substancje humusowe. W oparciu o uzyskane wyniki stwierdzono, że proporcje pomiędzy składnikami EPS są zbliżone dla reaktorów zasilanych ściekami syntetycznymi i wynosiły: białka 40-65%, cukry 26-45% i kwasy humusowe 7-17%, podczas gdy EPS osadu czynnego poddanego działaniu rzeczywistych odcieków wysypiskowych zawierało 50-62% cukrów a resztę w równych proporcjach stanowiły białka i kwasy humusowe. Całkowita ilość EPS (suma cukrów, białek i substancji humusowych) była zależna od obciążenia ładunkiem azotu amonowego, aczkolwiek stres wynikający z obecności substancji toksycznych zawartych w ściekach oraz krótki wiek osadu mogły również wpłynąć na ilość powstałego EPS.