Related Experiment Video
Updated: May 30, 2026
08:13
A Novel Bioreactor for High Density Cultivation of Diverse Microbial Communities
Published on: December 25, 2015
Molecular identification of the microbial diversity in two sequencing batch reactors with activated sludge
Martin Denecke1, Sascha Eilmus, Nadine Röder
1Department of Waste and Urban Water Management, Faculty of Civil Engineering, University of Duisburg-Essen, Essen, Germany. martin.denecke@uni-due.de
Applied Microbiology and Biotechnology
|July 26, 2011
Summary
Intermittent aeration in sequencing batch reactors significantly boosted microbial diversity compared to constant aeration. This finding highlights how controlled disturbances can enhance microbial ecosystems.
Area of Science:
- Environmental Microbiology
- Wastewater Treatment Technologies
Background:
- Sequencing batch reactors (SBRs) are widely used in wastewater treatment.
- Understanding microbial community dynamics is crucial for optimizing SBR performance.
- Aeration strategies can influence microbial diversity and ecosystem function.
Purpose of the Study:
- To compare the microbial community diversity in intermittently aerated SBRs versus continuously aerated SBRs.
- To investigate the impact of different aeration regimes on biomass, organic carbon, and nitrogen removal.
- To determine the taxonomic composition of microbial communities under varying aeration conditions.
Main Methods:
- Operation of two lab-scale sequencing batch reactors for 115 days.
- One reactor with intermittent aeration (2h aerobic/2h anaerobic), the other with continuous aeration.
- Monitoring of biomass (dry matter), chemical oxygen demand (COD), and nitrogen degradation.
- Microbial community composition analysis using terminal restriction fragment length polymorphism (T-RFLP) with multiple restriction enzymes.
Main Results:
- No significant differences in biomass, COD, or nitrogen degradation between the two aeration strategies.
- Significantly different microbial community compositions were observed at the end of the experiment.
- Species richness was at least five-fold higher in the intermittently aerated reactor.
Conclusions:
- Intermittent aeration strategies can lead to significantly higher microbial diversity in SBRs.
- Ecosystem disturbances, such as intermittent aeration, can promote greater species richness.
- While bulk parameters showed no difference, aeration strategy profoundly impacts microbial community structure.
More Related Videos
12:46Bromodeoxyuridine (BrdU) Labeling and Subsequent Fluorescence Activated Cell Sorting for Culture-independent Identification of Dissolved Organic Carbon-degrading Bacterioplankton
Published on: September 10, 2011
15:19Development of Sulfidogenic Sludge from Marine Sediments and Trichloroethylene Reduction in an Upflow Anaerobic Sludge Blanket Reactor
Published on: October 15, 2015
Related Concept Videos
01:29Modern Molecular Taxonomy
Advancements in molecular biology have revolutionized the identification and characterization of bacteria, with multiple methods leveraging DNA sequencing for enhanced precision. As sequencing technologies improve and costs decline, these approaches are increasingly used in clinical, environmental, and evolutionary studies.Multilocus Sequence Typing (MLST) examines several housekeeping genes, essential chromosomal genes encoding cellular functions, to distinguish strains. Approximately...
01:20Applications of Molecular Taxonomy
Molecular taxonomy has revolutionized the understanding and classification of bacteria, providing precise insights into their diversity, evolutionary relationships, and ecological roles. By utilizing molecular techniques such as DNA sequencing and fingerprinting, researchers have made significant strides in various fields related to bacterial studies.Resolving Taxonomic AmbiguitiesMolecular taxonomy has been instrumental in distinguishing closely related bacterial species initially thought to...
01:30Microbial Wastewater Treatment
Microbial communities in aquatic ecosystems play a key role in the natural breakdown of contaminants introduced through domestic and industrial effluents. Acting as biological catalysts, these microbes change and mineralize a wide range of organic and inorganic pollutants under different redox conditions.In oxygen-rich surface waters, aerobic heterotrophs lead organic matter breakdown, using oxygen as the terminal electron acceptor to efficiently oxidize substrates to carbon dioxide and water.
01:19Methods to Assess Microbial Communities
Microbial communities, comprising bacteria, archaea, and eukaryotic microorganisms, inhabit diverse ecosystems and play crucial roles in environmental and biological processes. Their diversity is defined by three main parameters: species richness (the number of distinct species), species abundance (the relative quantity of each species), and species evenness (how uniformly individual species are distributed in various locations). These factors together shape the structure and ecological balance...
01:24Automated Microbial Diagnostics
Automated diagnostic analyzers have transformed clinical microbiology by providing rapid and reliable methods for pathogen identification and antibiotic susceptibility testing. Among these systems, the Vitek 2 is widely used because it automates the traditionally labor-intensive processes of microbial identification (ID) and antibiotic susceptibility testing (AST), delivering standardized and timely results that are essential for effective patient care.Microbial Identification with ID CardsThe...
01:18Bioreactor Controls-II
In aerobic fermentations, oxygen is vital for microbial growth and metabolite production. Since air comprises only about 20% oxygen and the gas is poorly soluble in water—just 9 ppm at 20°C—supplying sufficient oxygen becomes a critical challenge, especially in high-demand processes like yeast growth or citric acid production. Even a fully saturated broth may offer only a few seconds of oxygen availability.To address this, sterile or scrubbed air is introduced into the fermentor via a sparger...