Glycolate excretion by air-grown Euglena graeilis z.

In contrast to reported fact, the air-grown cells of Euglena gracilis z were found to excrete glycolate into the surrounding medium, when placed in an atmosphere of 100% O2 under illumination at 20000 lux at the same rate of the 5% CO2-grown cells, but with a lag phase of about 30 min. The lag was eliminated by lowering intracellular CO2 concentration in the air-grown cells.