443 



50- 



> 



O 



If) 

 < 



CD 



20 



E 

 2 



Light On , 

 (1000 Lux) \ 



Scenedesmus 



-Mutont 



20 40 60 80 100 



TIME (MINUTES) 



120 



140 



Fig. 1. Curves illustrating the dark and light production of 



hydrogen gas by Ho adapted normal and mutant type Scene - 

 desmus . 0; "wild type" • 



1 1 . See Table I for experimental conditions. 



I, mutant 



8.0 - 



7.0 



6.0 



S 5.0 



o 



> 



3 



4.0 



I 3.0 



2.0 



1.0 



CONTROL 



60 80 100 120 140 



TIME (MINUTES) 



Fig. 2. The influence of DCMU on hydrogen production by adapted 

 cells of Scenedesmus . 0; Control, 



0, 4 X 10-7m DCMU, © 



0, 



» — -» » 



4 X 10~"M DCMU. Note break in the time axis during dark 



fermentati on. 



