Just the Right Amount: The Effect of Higher Salinity on Picochlorum oklahomense Cell Density

Abstract

Normally, too much salt can be deadly, but with Picochlorum oklahhomense is that the case? This halophilic algae thrives in high salinity using the salt to grow lipids, so we hypothesize that more salt will result in a higher cell count. We tested 2 bioreactors at a regular 2% salinity for the control group, then used an extremely high salinity of 10% for the 2 bioreactors for our experimental group. Our results contradicted our hypothesis, because the 10% salinity barely grew any algae at all. The average change in cell count of our 2% salinity control group was 28348 cells/µL compared to our 10% salinity with 1198 cells/µL. Since 10% did not support our hypothesis, we changed our experimental group from 10% to 5%. The average cell count change for our two, 5% bioreactors was 15225 cells/µL compared to the 2% control bioreactors of 12965 cells/µL which supports our hypothesis. We suggest that the BiRAQC researchers keep the salinity levels higher than normal for optimum algae growth for biofuels.