Assessing the abundance and activity of denitrifying polyphosphate accumulating organisms through molecular and chemical techniques

2010 ◽  
Vol 61 (8) ◽  
pp. 2061-2068 ◽  
Author(s):  
Adrian Oehmen ◽  
Gilda Carvalho ◽  
Filomena Freitas ◽  
Maria AM Reis
Keyword(s):  
In Situ Hybridisation ◽  
Analytical Techniques ◽  
Biological Nutrient Removal ◽  
Future Research ◽  
Fluorescence In Situ Hybridisation ◽  
Batch Tests ◽  
Oxygen Requirements ◽  
Polyphosphate Accumulating Organisms ◽  
Quantitative Fluorescence

Biological nutrient removal (BNR) plants can reduce both carbon and oxygen requirements by increasing the fraction of phosphorus (P) removed by denitrifying polyphosphate accumulating organisms (DPAOs). Contrasting findings have been reported in literature concerning whether or not PAOs and DPAOs are different microorganisms. In this study, quantitative fluorescence in situ hybridisation (FISH) measurements from different EBPR sludges support the hypothesis that PAOs and DPAOs are phyogenetically different. This experimental evidence is discussed within the context of literature findings and suggestions for future research concerning the identity of PAOs and DPAOs are proposed. Further, this paper discusses the different methodologies available for assessing the DPAO fraction through chemical analytical techniques, where the relative fraction estimated is highly dependent on the methodology employed. Thus, we recommend an alteration to previously proposed methods in order to calculate the DPAO fraction through anaerobic-anoxic and anaerobic-aerobic batch tests. This information is expected to be valuable in studies focussed on optimising the amount of phosphorus removal achieved with simultaneous denitrification.

Microbial quantification in activated sludge: the hits and misses

2003 ◽  
Vol 48 (3) ◽  
pp. 121-126 ◽  
Author(s):  
S.J. Hall ◽  
J. Keller ◽  
L.L. Blackall
Keyword(s):  
Activated Sludge ◽  
Molecular Genetic ◽  
In Situ Hybridisation ◽  
Biological Nutrient Removal ◽  
Physical Parameters ◽  
Fluorescence In Situ Hybridisation ◽  
Batch Tests ◽  
Polymerase Chain ◽  
Key Microorganisms

Since the implementation of the activated sludge process for treating wastewater, there has been a reliance on chemical and physical parameters to monitor the system. However, in biological nutrient removal (BNR) processes, the microorganisms responsible for some of the transformations should be used to monitor the processes with the overall goal to achieve better treatment performance. The development of in situ identification and rapid quantification techniques for key microorganisms involved in BNR are required to achieve this goal. This study explored the quantification of Nitrospira, a key organism in the oxidation of nitrite to nitrate in BNR. Two molecular genetic microbial quantification techniques were evaluated: real-time polymerase chain reaction (PCR) and fluorescence in situ hybridisation (FISH) followed by digital image analysis. A correlation between the Nitrospira quantitative data and the nitrate production rate, determined in batch tests, was attempted. The disadvantages and advantages of both methods will be discussed.

scholarly journals Fluorophores from fungi

2003 ◽  
Vol 24 (3) ◽  
pp. 12 ◽  
Author(s):  
Duncan Veal ◽  
Philip Bell ◽  
Hayley Brown ◽  
Hung-Yoon Choi ◽  
Peter Karuso
Keyword(s):  
Nucleic Acid ◽  
Real Time ◽  
Dna Microarray ◽  
Differential Display ◽  
Real Time Pcr ◽  
In Situ Hybridisation ◽  
Analytical Techniques ◽  
Fluorescence In Situ Hybridisation

Fluorescence has many advantages over traditional colour and radioactive labels, and is playing an increasingly important role in the most powerful analytical techniques. For example, fluorescence is at the heart of many nucleic acid based diagnostics (e.g. DNA microarray, real time-PCR, fluorescence in situ hybridisation, etc), immunofluorescence assays, defined substrate technologies and differential display proteomics and is gradually replacing or complementing other techniques based on colour or radiolabels.

Applicability of experience from laboratory reactors with biological phosphorus removal in full-scale plants

2006 ◽  
Vol 54 (1) ◽  
pp. 267-275 ◽  
Author(s):  
E. Tykesson ◽  
L.L. Blackall ◽  
Y. Kong ◽  
P.H. Nielsen ◽  
J. la Cour Jansen
Keyword(s):  
Phosphorus Removal ◽  
Wastewater Treatment Plants ◽  
In Situ Hybridisation ◽  
Full Scale ◽  
Fluorescence In Situ Hybridisation ◽  
Biological Phosphorus Removal ◽  
Batch Tests ◽  
P Release ◽  
Biological Phosphorus

Enhanced biological phosphorus removal (EBPR) has been used at many wastewater treatment plants all over the world for many years. In this study a full-scale sludge with good EBPR was tested with P-release batch tests and combined FISH/MAR (fluorescence in situ hybridisation and microautoradiography). Proposed models of PAOs and GAOs (polyphosphate- and glycogen-accumulating organisms) and microbial methods suggested from studies of laboratory reactors were found to be applicable also on sludge from full-scale plants. Dependency of pH and the uptake of both acetate and propionate were studied and used for calculations for verifying the models and results from microbial methods. All rates found from the batch tests with acetate were higher than in the batch tests with propionate, which was explained by the finding that only those parts of the bacterial community that were able to take up acetate anaerobically were able to take up propionate anaerobically.

The effect of GAOs (glycogen accumulating organisms) on anaerobic carbon requirements in full-scale Australian EBPR (enhanced biological phosphorus removal) plants

2003 ◽  
Vol 47 (11) ◽  
pp. 37-43 ◽  
Author(s):  
A.M. Saunders ◽  
A. Oehmen ◽  
L.L. Blackall ◽  
Z. Yuan ◽  
J. Keller
Keyword(s):  
Phosphorus Removal ◽  
In Situ Hybridisation ◽  
Full Scale ◽  
Fluorescence In Situ Hybridisation ◽  
Enhanced Biological Phosphorus Removal ◽  
Biological Phosphorus Removal ◽  
Accumulibacter Phosphatis ◽  
Polyphosphate Accumulating Organisms ◽  
Biological Phosphorus

Glycogen-accumulating organisms (GAOs) were present in six full-scale plants investigated and in all but one made a significant contribution to the amount of volatile fatty acid (VFA) taken up anaerobically. While most plants surveyed contain GAOs, it was demonstrated that it is possible for a full-scale plant to operate with an insignificant GAO population.“Candidatus Accumulibacter phosphatis”were the significant polyphosphate-accumulating organisms (PAOs) in all plants surveyed. “Candidatus Competibacter phosphatis” were found in all plants along with other possible GAOs that were observed but not identified. A significant GAO population will increase the carbon requirements by removing VFA that could otherwise have been used by PAOs. Process optimization minimizing GAOs in full-scale plants would lead to a more efficient use of VFA. Enhanced biological phosphorus removal (EBPR), fluorescence in situ hybridisation (FISH), glycogen accumulating organism (GAO); polyphosphate accumulating organism (PAO);

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