Conditions of H2 production
|
Time of illumination following dark anaerobic incubation (h)
|
---|
0.25
|
1
|
3
|
5
|
24
|
---|
Control (HS)
|
H2 produced (µl/ml)
|
3.46
|
3.86
|
8.41
|
10.80
|
27.47
|
Efficiency (%)
|
1.43
|
0.40
|
0.29
|
0.22
|
0.11
|
+ Glc + GO + Asc
|
H2 produced (µl/ml)
|
n.d.
|
38.57
|
85.33
|
92.68
|
117.04
|
Efficiency (%)
|
n.d.
|
4.00
|
2.95
|
1.92
|
0.51
|
+ O2 absorbent
|
H2 produced (µl/ml)
|
3.85
|
6.73
|
13.09
|
19.20
|
62.10
|
Efficiency (%)
|
1.60
|
0.70
|
0.45
|
0.40
|
0.27
|
- Algal cultures containing 50 µg chl (a + b)/ml and dark-incubated for 4 h were illuminated using cool white fluorescent tubes, at an intensity of 52 W/m2, corresponding to approx. 320 µmol photons/m2/s. See “Materials and methods” for the calculations on the incident light-to-H2 conversion efficiency. The experiments were carried out in HS medium (control) and the effects of a combined glucose (Glc, 2 mM), glucose oxidase (GO, 0.2 mg/ml) and ascorbate (Asc, 1 mM) treatment and the effects of an iron-salt O2 absorbent were also assessed
- nd non-determined