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Updated: Jul 12, 2026
08:13
A Novel Bioreactor for High Density Cultivation of Diverse Microbial Communities
Published on: December 25, 2015
Algal Cultures: Ability To Reduce Turbulent Friction in Flow
Science (New York, N.Y.)
|September 24, 1965
Summary
Algal growth in liquid cultures reduces the pressure needed for fluid flow, thanks to secreted polysaccharides. These findings aid in understanding algal fluid dynamics and polymer properties.
Area of Science:
- Biochemistry
- Fluid Dynamics
- Microbiology
Background:
- Algal cultures alter the physical properties of their surrounding medium.
- Understanding these changes is crucial for various applications, from industrial processes to ecological studies.
Purpose of the Study:
- To investigate the impact of algal growth on the rheological properties of liquid cultures.
- To identify the specific biomolecules responsible for observed changes in fluid flow.
- To explore the use of fluid dynamics measurements for characterizing algal exopolymers.
Main Methods:
- Culturing freshwater and marine algae in liquid media.
- Measuring the pressure drop across a pipe for both pure media and algal cultures.
- Utilizing friction measurements to analyze fluid properties and estimate polysaccharide molecular weight.
- Assessing the influence of bacterial activity on the algal polymer.
Main Results:
- Algal cultures exhibited reduced flow resistance compared to the pure liquid medium.
- This phenomenon was attributed to the production of long-chain polysaccharides by the algae.
- Friction measurements provided a method for estimating the molecular weight of the algal polysaccharide.
- Bacterial action was observed to affect the polymer's properties.
Conclusions:
- Algal exopolysaccharides significantly alter fluid flow characteristics.
- Fluid friction measurements offer a viable approach for characterizing algal polymers and their degradation.
- This research provides insights into the biophysical interactions within algal cultures.
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