Induction of reactive oxygen species in marine phytoplankton under crude oil exposure

• Published in: Environmental science and pollution research international Vol. 22; no. 23; pp. 18874 - 18884
• Main Authors: Ozhan, Koray, Zahraeifard, Sara, Smith, Aaron P, Bargu, Sibel
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.12.2015; Springer Nature B.V
• Subjects: Algae; Antioxidants; Aquatic Pollution; Atmospheric Protection/Air Quality Control/Air Pollution; Cell cycle; cell growth; chlorophyll; Chlorophyll - analogs & derivatives; Chlorophyll - metabolism; Crude oil; Diatoms - drug effects; Diatoms - growth & development; Diatoms - metabolism; Dinoflagellida - drug effects; Dinoflagellida - growth & development; Dinoflagellida - metabolism; Dinophyceae; Ditylum; DNA; Earth and Environmental Science; Ecotoxicology; Environment; Environmental Chemistry; Environmental Health; Enzymes; Exposure; food webs; Gene expression; genes; glutathione; Glutathione - metabolism; Hydrocarbons; Indicator organisms; Investigations; Laboratories; Lipid peroxidation; Lipid Peroxidation - drug effects; Lipids; Louisiana; microalgae; Nucleic acids; Oceanography; Oil spills; Oxidative stress; Peroxidation; petroleum; Petroleum - metabolism; Petroleum - toxicity; Physiological responses; Physiology; Phytoplankton; Phytoplankton - drug effects; Phytoplankton - growth & development; Phytoplankton - metabolism; Plankton; Population growth; proteins; reactive oxygen species; Reactive Oxygen Species - metabolism; Research Article; stress response; Studies; superoxide dismutase; Superoxide Dismutase - metabolism; Toxicity; Waste Water Technology; Water Management; Water Pollutants, Chemical - toxicity; Water pollution; Water Pollution Control; Louisiana; United States > US; Phytoplankton; The deepwater horizon oil spill; Reactive oxygen species; Crude oil
• DOI: 10.1007/s11356-015-5037-y
• ISSN: 0944-1344; 1614-7499

Exposure of phytoplankton to the water-accommodated fraction of crude oil can elicit a number of stress responses, but the mechanisms that drive these responses are unclear. South Louisiana crude oil was selected to investigate its effects on population growth, chlorophyll a (Chl a) content, antioxidative defense, and lipid peroxidation, for the marine diatom, Ditylum brightwellii, and the dinoflagellate, Heterocapsa triquetra, in laboratory-based microcosm experiments. The transcript levels of several possible stress-responsive genes in D. brightwellii were also measured. The microalgae were exposed to crude oil for up to 96 h, and Chl a content, superoxide dismutase (SOD), the glutathione pool (GSH and GSSG), and lipid peroxidation content were analyzed. The cell growth of both phytoplankton species was inhibited with increasing crude oil concentrations. Crude oil exposure did not affect Chl a content significantly in cells. SOD activities showed similar responses in both species, being enhanced at 4- and 8-mg/L crude oil exposure. Only H. triquetra demonstrated enhanced activity in GSSG pool and lipid peroxidation at 8-mg/L crude oil exposure, suggesting that phytoplankton species have distinct physiological responses and tolerance levels to crude oil exposure. This study indicated the activation of reactive oxygen species (ROS) in phytoplankton under crude oil exposure; however, the progressive damage in cells is still unknown. Thus, ROS-related damage in nucleic acid, lipids, proteins, and DNA, due to crude oil exposure could be a worthwhile subject of study to better understand crude oil toxicity at the base of the food web.