The Effects of Micro-Algae Characteristics on the Bioremediation Rate of Deepwater Horizon Crude Oil

Crude oil spills have extensively harmed ecosystems. Current spill treatments are limited by high costs, hazardous by-products, and unsustainability. Algae crude oil bioremediation has been an obscure field in research. We sought to examine the potential of algae bioremediation as a treatment for crude oil spills. This study investigated whether different algal characteristics would influence the degradation rates of Deepwater Horizon crude oil. Eight algae were utilized: Aphanocapsa sp., Chlorella autotrophica, Coccochloris elabens, Dunaliella tertiolecta, Oscillatoria sp., Scenedesmus obliquus, Synechococcus elongatus, and Volvox aureus. Algal growth in heavy crude conditions was analyzed via spectrophotometry and computer image processing techniques. We hypothesized that motility, levels of chlorophyll a & b, and multicellularity would affect algae bioremediation rates. Test tubes containing algae and control test tubes that lacked algae, placed under fluorescent lighting, contained freshwater or seawater solution and the crude oil. Crude oil and water levels were recorded for fifteen days. The data was analyzed for correlations between the specific algal characteristics and degradation rates. Results revealed the algae degraded up to a significant 35% of the crude. Correlations between algal characteristics and bioremediation rates were not observed, so the hypotheses were unsupported. However, two important conclusions were deduced: algae can degrade “heavy” crude oil and they can thrive in high crude conditions, abilities that are necessary for bioremediation. From this study, we have demonstrated that properly-controlled algae are viable agents for crude oil bioremediation.