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Published on: August 4, 2023
The surface activity of Acinetobacter calcoaceticus sp. 2CA2
1Biochemical Engineering Research Unit, Department of Chemical Engineering, McGill University, 3480 University Street, Montreal, Quebec, Canada, H3A 2A7.
Biotechnology and Bioengineering
|September 1, 1984
Summary
Acinetobacter calcoaceticus sp. 2CA2 cells and their lipopeptide product significantly alter surface tension and stabilize/destabilize emulsions. This hydrocarbon-degrading bacterium exhibits unique surface-active properties.
Area of Science:
- Microbiology
- Biochemistry
- Environmental Science
Background:
- Acinetobacter calcoaceticus sp. 2CA2 metabolizes hydrocarbons, a process linked to changes in culture broth surface tension.
- Surface activity is observed only during growth on liquid hydrocarbons, not soluble substrates.
Purpose of the Study:
- To investigate the surface-active properties of Acinetobacter calcoaceticus sp. 2CA2 during hydrocarbon metabolism.
- To characterize the role of whole cells and extracellular products in surface tension reduction and emulsion formation/stabilization.
Main Methods:
- Culturing Acinetobacter calcoaceticus sp. 2CA2 on liquid hydrocarbons and soluble substrates.
- Measuring surface tension of culture broth and cell suspensions.
- Assessing emulsion formation and stabilization capabilities of cells and extracellular lipopeptide.
- Evaluating de-emulsification of stabilized emulsions.
Main Results:
- Whole cells of Acinetobacter sp. 2CA2 significantly reduce surface tension during hydrocarbon growth.
- Both surface-active and non-surface-active cells, along with an extracellular lipopeptide, can form and stabilize kerosene-water emulsions.
- The extracellular lipopeptide effectively breaks down surfactant-stabilized emulsions, drastically reducing emulsion half-life.
Conclusions:
- Acinetobacter calcoaceticus sp. 2CA2 possesses distinct surface-active properties linked to hydrocarbon metabolism.
- Both cellular components and an extracellular lipopeptide contribute to emulsion dynamics.
- The lipopeptide shows potential for de-emulsification applications.
