Stimulation of methanol degradation in UASB reactors: In situ versus pre-loading cobalt on anaerobic granular sludge

2004 ◽  
Vol 87 (7) ◽  
pp. 897-904 ◽  
Author(s):  
Marcel H. Zandvoort ◽  
Jarno Gieteling ◽  
Gatze Lettinga ◽  
Piet N.L. Lens
Keyword(s):  
Granular Sludge ◽  
Anaerobic Granular Sludge ◽  
Uasb Reactors ◽  
Stimulation Of

Microbial community evaluation of anaerobic granular sludge from a hybrid reactor treating pentachlorophenol by using fluorescence in situ hybridization

2003 ◽  
Vol 48 (6) ◽  
pp. 65-73 ◽  
Author(s):  
M.A.P. Montenegro ◽  
J.C. Araujo ◽  
R.F. Vazoller
Keyword(s):  
In Situ Hybridization ◽  
Microbial Community ◽  
Methanogenic Archaea ◽  
Granular Sludge ◽  
Hybrid Reactor ◽  
Anaerobic Granular Sludge ◽  
Bacterial Cells ◽  
Before And After ◽  
Community Evaluation

We used in situ hybridization with fluorescently labeled rRNA-targeted oligonucleotide probes concurrently with microscopic examinations and methane measurements to characterize the microbial community of an anaerobic hybrid reactor treating pentachlorophenol (PCP) with a mixture of fatty acids (propionic, butyric, acetic and lactic) and methanol. Archaeal cells detected with probe ARC915 prevailed in anaerobic granular sludge without and with the addition of PCP in a range of 2.0 to 21.0 mg/L to the reactor. This group accounted for 81 and 90% of the DAPI-stained cells before and after the addition of 21 mg/L of PCP, respectively. In these conditions, cells detected with the Methanosarcinales specific probe (MSMX860) were the only methanogenic Archaea found and accounted for 59 to 87.6% of the DAPI-stained cells. No cells were detected by the Methanomicrobiales (MG1200), Methanobacteriaceae (MB1174) and Methanococcaceae (MC1109) specific probes. Bacterial cells detected with probe EUB338 were found in very low numbers, which ranged from 5.7 to 1.0% of the DAPI-stained cells. This finding agrees with the scanning electron microscope examinations, in which cells morphologically resembling Methanosaeta and Methanosarcina were predominantly observed in the granular sludge. Results contributed to the investigation of the importance of the methanogens during PCP degradation.

Immobilization of biogenic Pd(0) in anaerobic granular sludge for the biotransformation of recalcitrant halogenated pollutants in UASB reactors

2015 ◽  
Vol 100 (3) ◽  
pp. 1427-1436 ◽  
Author(s):  
Aurora M. Pat-Espadas ◽  
Elías Razo-Flores ◽  
J. Rene Rangel-Mendez ◽  
Juan A. Ascacio-Valdes ◽  
Cristobal N. Aguilar ◽  
...  
Keyword(s):  
Granular Sludge ◽  
Anaerobic Granular Sludge ◽  
Halogenated Pollutants ◽  
Uasb Reactors

Immobilization of metal–humic acid complexes in anaerobic granular sludge for their application as solid-phase redox mediators in the biotransformation of iopromide in UASB reactors

2016 ◽  
Vol 207 ◽  
pp. 39-45 ◽  
Author(s):  
Aracely S. Cruz-Zavala ◽  
Aurora M. Pat-Espadas ◽  
J. Rene Rangel-Mendez ◽  
Luis F. Chazaro-Ruiz ◽  
Juan A. Ascacio-Valdes ◽  
...  
Keyword(s):  
Humic Acid ◽  
Solid Phase ◽  
Granular Sludge ◽  
Anaerobic Granular Sludge ◽  
Redox Mediators ◽  
Uasb Reactors ◽  
As Solid Phase

Cultivation of anaerobic granular sludge in UASB reactors with aerobic activated sludge as seed

1987 ◽  
Vol 21 (7) ◽  
pp. 789-799 ◽  
Author(s):  
Weimin Wu ◽  
Jicui Hu ◽  
Xiasheng Gu ◽  
Yizhang Zhao ◽  
Hui Zhang ◽  
...  
Keyword(s):  
Activated Sludge ◽  
Granular Sludge ◽  
Anaerobic Granular Sludge ◽  
Uasb Reactors

Reductive biodegradation of 1,2-dichloroethane by methanogenic granular sludge: perspectives for in situ remediation

2002 ◽  
Vol 45 (10) ◽  
pp. 43-48 ◽  
Author(s):  
S. De Wildeman ◽  
H. Nollet ◽  
H. Van Langenhove ◽  
G. Diekert ◽  
W. Verstraete
Keyword(s):  
Energy Source ◽  
16S Rrna ◽  
Granular Sludge ◽  
In Situ Remediation ◽  
Electron Sources ◽  
Positive Strain ◽  
Conversion Rates ◽  
The Media ◽  
Uasb Reactors

Granular methanogenic sludge was able to dechlorinate 1,2-dichloroethane (1,2-DCA) to ethene in UASB reactors. Ethanol served as the sole carbon and energy source. The average dechlorination rate measured on the basis of ethene production varied between 1.7 and 2.1 μmol 1,2-DCA/(h.gVSS) (46.7 and 57.4 mg/L.d). In order to elucidate the microbial origin of this bioconversion, enrichment cultures of the methanogenic sludge were prepared with different carbon and electron sources: pyruvate, lactate, H2/CO2, ethanol and formate. Dithiothreitol (DTT) was the strong reductant in order to increase the negative redox potential in the media. A homo-acetogenic gram-positive strain could be isolated in the presence of formate. 16S rRNA of the isolated strain showed that the bacterium was closely related (99.7%) to Acetobacterium wieringae. The strain also grew on pyruvate, lactate, H2/CO2 and ethanol, although dechlorination rates of 1,2-DCA were at least 5 times higher when formate was the (only) electron source. Average conversion rates reached 3 μmol/(h.gdry cells) and appeared to relate to cometabolic biocatalysis on the corrinoid centers of the homo-acetogenic strain. Some perspectives of anaerobic in situ bioremediation of groundwater polluted with chloroethanes are presented.

Molecular ecology of anaerobic granular sludge grown at different conditions

2003 ◽  
Vol 48 (6) ◽  
pp. 57-64 ◽  
Author(s):  
E. Díaz ◽  
R. Amils ◽  
J.L. Sanz
Keyword(s):  
Inner Core ◽  
Molecular Ecology ◽  
Methanogenic Archaea ◽  
Granular Sludge ◽  
Anaerobic Granular Sludge ◽  
Bacterial Cells ◽  
High Concentration ◽  
Qualitative And Quantitative ◽  
Low Concentrations

Qualitative and quantitative diversity of microorganisms present in anaerobic granular sludges fed with different substrates, as well as the structure of these granules have been studied using fluorescent 16S rRNA-targeted in situ hybridization and electron microscopy. The granules showed a multi-layered structure, in which both densely packed and loose micro-colonies, channels and holes could be observed. Only bacteria were found in the outer shell of the granules, while both archaea and bacteria were detected in the inner core. Although high cell density was found in the granules (more than 1011 cells/gram, determined by DAPI-stain) only a low percentage of cells was able to hybridize with the rRNA-targeted probes. Significant quantitative and qualitative differences were observed in the composition of granules fed with different substrates (formate, acetate at high and low concentrations, propionate, sucrose, starch and peptone). Bacterial cells were mostly gram-positives. Active proteobacteria were scarce in the granules exposed to VFA. Syntrophobacteria became dominant in the propionate-grown biomass. Concerning methanogenic archaea, Methanosaeta was the predominant species using complex substrates or low acetate concentration fed granules, while Methanosarcina and members of Methanobacteriales were predominant in the granules grown at high concentration of acetate or formate, respectively. Other Methanomicrobiales and Methanococcales, have been detected in the anaerobic granular sludge in the conditions used in this work.

Characterization of anaerobic granular sludge developed in UASB reactors that treat ethanol, carbohydrates and hydrolyzed protein based wastewaters

2008 ◽  
Vol 57 (6) ◽  
pp. 837-842 ◽  
Author(s):  
F. Molina ◽  
C. García ◽  
E. Roca ◽  
J. M. Lema
Keyword(s):  
Distribution Density ◽  
Granular Sludge ◽  
Treated Wastewater ◽  
Uasb Reactor ◽  
Anaerobic Granular Sludge ◽  
Hydrolyzed Protein ◽  
Different Types ◽  
Micro Organisms ◽  
Uasb Reactors

In this work, granules developed from UASB reactors that treat different types of wastewaters (ethanol, carbohydrates and protein-based synthetic wastewaters) were studied. Granule parameters (size distribution; density; settlement characteristics; elemental composition; acidogenic and methanogenic activities) were analyzed along with micro-organisms identified by FISH to better understand granule behavior and its formation process. Micro-organisms distributions in anaerobic granules are highly dependent on the type of treated wastewater. Granules developed in a UASB reactor that treats wastewater with a high content of carbohydrates presented high acidogenic bacteria colonization. Members of Methanosaetaceae were the dominant methanogens in the studied granules, and Methanobacteriales appear to be co-dominant in the granules developed with carbohydrates and protein-based wastewaters.

Quantification of methanogen cell density in anaerobic granular sludge consortia by fluorescence in-situ hybridization

2000 ◽  
Vol 42 (3-4) ◽  
pp. 77-82 ◽  
Author(s):  
T. Tagawa ◽  
K. Syutsubo ◽  
Y. Sekiguchil ◽  
A. Ohashi ◽  
H. Harada
Keyword(s):  
In Situ Hybridization ◽  
Fluorescence In Situ Hybridization ◽  
Cell Density ◽  
Methane Production ◽  
Granular Sludge ◽  
Fish Analysis ◽  
Anaerobic Granular Sludge ◽  
Strongly Correlated ◽  
Production Activity

Whole cell fluorescence in-situ hybridization (FISH) with 16S rRNA targeted oligonucleotides was applied to reveal the microbial ecological structure of UASB-grown granular sludge. The FISH analysis indicated that the members of the domain Archaea accounted for 28 to 53% of the total cells in various granular sludge sources, while Methanosaeta and Methanobacteriaceae cells accounted for 13 to 38%, and 4 to 27%, respectively. Methanosaeta cell density and Methanobacteriaceae cell density were strongly correlated, respectively, with acetate-utilizing methane production activity and with hydrogen-utilizing methane production activity.

Hydrophilicity/hydrophobicity of anaerobic granular sludge surface and their causes: An in situ research

2016 ◽  
Vol 220 ◽  
pp. 117-123 ◽  
Author(s):  
Yiyu Li ◽  
Ping Zheng ◽  
Meng Zhang ◽  
Zhuo Zeng ◽  
Zhiyao Wang ◽  
...  
Keyword(s):  
Granular Sludge ◽  
Anaerobic Granular Sludge
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