jong-woo park, wonho yih department of oceanography, kunsan national university mpm ecology &...
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Jong-Woo Park, Wonho YihJong-Woo Park, Wonho Yih
Department of Oceanography,Department of Oceanography,
Kunsan National UniversityKunsan National University
MPM Ecology & Technology Laboratory
Photobiological H2 production by Korean N2-fixing unicellualr cyanobacterial strains
2010 NHA Hydrogen
Conference & Expo
1. Background
2. Photobiological H2 production by cyanobacteria
3. Material & Method
4. Result
5. Conclusion
6. Further study
1. Background
1-1. Shortage of fossil fuel
1-2. Environmental problems : greenhouse effect…
“Needs for clean energy production”
- wind
- tidal power
- solar energy
- hydrogen
“Different H2 producing micro-organisms ”
Cyanobacteria(Mitsui, 1981)
Green algae(Gaffron & Rubin, 1942)
Anaerobic bacteria(Yasuo, 1999)
1. Background
2. Photobiological H2 production by cyanobacteria
2-1. Cyanobacteria
- Present in all marine environment
- Photosynthetic prokaryote
- Some N2-fixers
2-2. H2 producing cyanobacteria
- H2 production under CO2-free condition
- Using N2ase & H2ase
2-3. Cyanobacterial H2 - clean energy
- sun light, H2O O2, H2
- cell as biocatalyst
- room-temperature reaction
(H2O 2H2, O2)
light
2. Photobiological H2 production by cyanobacteria
2-4. H2 production by N2-fixing cyanobacteria
photosynthesis: with CO2 → organic matter, O2
H2 production: without CO2 → H2O bio-photolysis
↗ O2
light ↗
H2O → → PS → (CH2O) ↗ ↗ CO2
(CH2O) → FD → H2ase, N2ase → H2
N2 + 8H+ + 16ATP → 2NH3 + H2 + 16ADP + 16Pi
2. Photobiological H2 production by cyanobacteria
3. Material & Method
3-1. Isolation of strains
3. Material & Method
Synechococcus sp. Miami BG043511
Cyanothece sp. KNU CB-MAL031
KNU CB-MAL058
* Size bar = 20um
3. Material & Method
- Bahama Island, 1981
- Garorim Bay, Taean, June 2006
- Garorim Bay, Taean, October 2006
3-2. High density culture (for 2wks)
- medium : f/2-BGER
- light : 100 μE m-2 s-1
- temperature : 20℃
- aeration : mixing effect
3. Material & Method
3-3. Synchronization of cell cycle (72hrs)
- NO3-free medium (N2ase activation)
- LD cycle (14 : 10)
- aeration (mixing)
3. Material & Method
- 350 μE m-2 s-1 (continuous)
- 20℃
3-4. H2 production (96hrs)
- flushing of head space w/ N2
3. Material & Method
range of cell density (108 ml-1)
- Low CD : 1~ 4
- Middle CD : 5~10
- High CD : 10~17
- 3ml flask-1
- connecting syringe
- cell suspension
3. Material & Method
3-4. H2 production (96hrs)
3-5. Measurement of produced H2
1. GC (SRI-8610C) w/ HID detector
2. Measuring interval :
0, 4, 12, 24, 36, 48, 72, 96 h
3. Material & Method
3. Material & Method
3-5. Measurement of produced H2
Incubation time (hr)
0 20 40 60 80 100
mL
H2 /
fla
sk
0.0
0.5
1.0
1.5
2.0
2.5
3.0
4. Result
H2 production per flask (w/ 3ml cell suspension)
Average H2
BG043511 : 1.37
CB031 : 1.55
CB058 : 0.83
Low
Cell density
4. Result
H2 production per flask (w/ 3ml cell suspension)
Medium
Cell density
Average H2
BG043511 : 2.04
CB031 : 5.56
CB058 : 4.06
4. Result
H2 production per flask (w/ 3ml cell suspension)
High
Cell density
Average H2
BG043511 : 1.73
CB031 : 2.66
CB058 : no product
To summarize…
H2 production per flask (w/ 3ml cell suspension)
4. Result
H2 production per billion cells
4. Result
To summarize…
5. Conclusion
1. CB031 & Miami BG043511 produced H2 at all the tested cell densities up to 15 × 108 cells ml-1.
2. Tested strains showed different ranges of cell densities for optimal H2 production
3. Maximum H2 production (ml H2 / flask)
Miami BG043511 : 6.26 (at high CD)
CB031 : 7.41 (at middle CD)
4. No H2 production detected over 15 × 108 cells ml-1
6. Further study
6-1. Searching for better strains
- temperature
- salinity
- life cycle
- light
6-2. Synchronization of cell cycle
Mitsui et al., 1986 (Nature)
6. Further study
6-3. Inhibition of H2 oxidation
S. Kumazawa, 2003 (Mar. Bio technology)
6. Further study
0
0.1
0.2
0.3
0.4
0.5
BG043511 CB031 CB058
Strains
ml
H2 f
las
k-1
CO
Control
6-3. Inhibition of H2 oxidation (Lab. data)
Thank you very much !