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Rhodospirillum rubrum: utilization of condensed corn solubles for poly-(3-hydroxybutyrate-co-3-hydroxyvalerate)
R L Smith1, T P West, W R Gibbons
1Department of Biology and Microbiology, South Dakota State University, Brookings, SD 57007, USA. beccaleigh@hotmail.com
Journal of Applied Microbiology
|January 9, 2008
Summary
A new, cost-effective growth medium using condensed corn solubles (CCS) was developed for Rhodospirillum rubrum. This medium supports polyhydroxyalkanoate biopolymer production effectively, potentially enabling commercial-scale manufacturing.
Area of Science:
- Microbiology
- Biotechnology
- Industrial Microbiology
Background:
- Polyhydroxyalkanoates (PHAs) are biodegradable polymers with diverse applications.
- Developing cost-effective production methods is crucial for commercial viability.
- Rhodospirillum rubrum is a bacterium capable of producing PHAs.
Purpose of the Study:
- To develop an economical growth medium for Rhodospirillum rubrum using condensed corn solubles (CCS), an ethanol production byproduct.
- To evaluate the efficacy of the CCS medium for PHA production.
Main Methods:
- Rhodospirillum rubrum growth trials were conducted in various media, including CCS, supplemented malate-ammonium medium (mSMN), and tryptic soy broth.
- Experiments involved small-scale cultures in serum bottles and controlled bioreactor conditions.
- Cell density, growth rate, and poly-(3-hydroxybutyrate-Co-3-hydroxyvalerate) production were measured.
Main Results:
- Condensed corn solubles (CCS) medium supported growth and PHA production comparable to defined media.
- Microaerophilic conditions in CCS medium yielded higher cell densities and growth rates than anaerobic conditions.
- Bioreactor cultivation in CCS medium demonstrated efficient PHA production (0.36% cell dry weight).
Conclusions:
- A cost-effective CCS-based medium was successfully developed for Rhodospirillum rubrum.
- The developed medium is as effective as traditional media for PHA production.
- This inexpensive medium holds potential for economical, commercial-scale biopolymer manufacturing.
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