FIG. 2.

Temperature and pH dependence of hydrogen production using W3110. A 50-ml cell suspension was mixed with a stirrer, and hydrogen production was initiated by adding 100 mM sodium formate to the reactor. The hydrogen production rates were plotted from the results of the initial hydrogen production rate. (A) Temperature dependence between 25°C and 60°C. (B) pH dependence between pH 5.0 and 8.0.