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Hydrogen Production and Utilization in a Membrane Reactor
Published on: March 10, 2023
Efficient hydrogen production from acetate through isolated Rhodobacter sphaeroides.
Jyumpei Kobayashi1, Kazuaki Yoshimune, Tomoe Komoriya
1Department of Applied Molecular Chemistry, Graduate School of Industrial Technology, Nihon University, 1-2-1, Izumichou, Narashino, Chiba 275-8575, Japan.
Journal of Bioscience and Bioengineering
|September 10, 2011
Summary
Researchers discovered a new photosynthetic bacterium, Rhodobacter sphaeroides HJ, that significantly boosts hydrogen production from acetate. This finding offers a promising avenue for efficient biohydrogen fuel generation.
Area of Science:
- Microbiology
- Biotechnology
- Renewable Energy
Background:
- Photosynthetic bacteria can produce hydrogen from organic acids like acetate and lactate.
- Coculture systems show promise for biohydrogen production.
- Rhodobacter sphaeroides RV exhibits high hydrogen production from lactate but lower yields from acetate.
Purpose of the Study:
- To screen for photosynthetic bacteria with high hydrogen production capabilities from acetate and lactate.
- To identify novel Rhodobacter sphaeroides strains for improved biohydrogen yields.
- To investigate metabolic pathways for enhanced acetate-to-hydrogen conversion.
Main Methods:
- Screening of photosynthetic bacteria from Japanese lakes and swamps.
- Isolation and identification of 76 Rhodobacter sphaeroides strains using 16S rRNA gene sequencing.
- Fermentation experiments to measure hydrogen production from acetate and lactate.
Main Results:
- Rhodobacter sphaeroides HJ was identified as the top-performing strain.
- Strain HJ produced 2300±93 ml/L-broth of hydrogen from 75mM acetate in 120h.
- Hydrogen production from acetate by strain HJ was 1.9-2.1 times higher than Rhodobacter sphaeroides RV.
- Strain HJ showed similar hydrogen production from both acetate and lactate.
Conclusions:
- Rhodobacter sphaeroides HJ demonstrates superior hydrogen production from acetate compared to existing strains.
- The metabolic pathway of strain HJ may hold the key to optimizing biohydrogen production from acetate.
- This discovery advances the potential for efficient and sustainable biohydrogen fuel generation.
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