Aquaculture Research
Center in Baltimore, MD. The algae were grown in photobioreactors
which consisted of 500-ml borosilicate glass bottles (Pyrex no. 1395;
diameter, 13.6 cm; height, 26.2 cm) with three ports in the cap. Two ports
were connected to tubes leading to the bottom of the bottle. Air was
pumped into these two ports through 0.22-m-pore-size syringe filters at
a rate of 5 liters/min to provide constant mixing and to provide the carbon
dioxide present in the air. The third port was used as a vent. The bottles
were positioned 25 cm from 215-W Phillips white fluorescent lights with
a light intensity of 275mol/m2/s at the front of the bottle and were grown
on a light-dark photoperiod of 14 and 10 h, respectively, at 25°C. Algae
were subcultured weekly using an inoculating volume of 10% and were
used for the experiments at an optical density at 600 nm (OD600) of 1.0
and a pH of 10.2.