title: Potential toxicity of ionic liquid ([C12mim]BF4) on the growth and biochemical characteristics of a marine diatom Phaeodactylum tricornutum.
abstract: Recently, some researchers have pointed out that the threats of ionic liquids (ILs) to aquatic environment cannot be ignored. Thus, this study investigated the potential toxicity of 1-dodecyl-3-methylimidazolium tetrafluoroborate ([C12mim]BF4) on a marine diatom Phaeodactylum tricornutum at population, biochemical and physiological levels using 96h growth tests with a batch-culture system. Results showed that [C12mim]BF4was very stable in aquatic environment during 96h of exposure. The growth of P. tricornutum was significantly inhibited by [C12mim]BF4with 24, 48, 72 and 96h EC50values of 0.63, 0.61, 0.68 and 0.72mgL-1, respectively. Although there were no significant differences between the controls and treatments with 0.1 and 0.5mgL-1[C12mim]BF4, the effective quantum yields (ΦPSII) of the diatom in 1, 2.5, 5 and 10mgL-1[C12mim]BF4treatments were 61.48, 17.04, 2.96 and 0.74% of that in the controls at 96h of exposure, respectively. Chl a content of the diatom was decreased by 34.86, 47.79, 49.81, 59.21, 79.82 and 86.98% compared with that of the controls at 96h of exposure in 0.1, 0.5, 1, 2.5, 5 and 10mgL-1[C12mim]BF4treatments, respectively. Relative to the controls, soluble sugar content, reactive oxygen species (ROS) level, malondialdehyde (MDA) content, superoxide dismutase (SOD) and peroxidase (POD) activities of the diatom increased with increasing [C12mim]BF4concentrations at 96h of exposure, and reached their maxima (1.46μg106cell-1, 7.48FU107cell-1, 3.35nmol108cell-1, 33.41 and 7.23Umg-1proteins, respectively) in 5mgL-1[C12mim]BF4treatments. While the maximum soluble protein content (1.56μg106cell-1) of the diatom was obtained in 0.5mgL-1[C12mim]BF4treatments, and then decreased with increasing [C12mim]BF4concentrations from 0.5 to 10mgL-1. These findings provide strong evidence for the potential toxicity of ILs to marine diatoms.
authors.affiliation: College of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang 212003, China. Electronic address: dengxy2009@126.com.
authors.forename: Xiang-Yuan
authors.initials: XY
authors.lastname: Deng
authors.affiliation: College of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang 212003, China.
authors.forename: Da
authors.initials: D
authors.lastname: Li
authors.affiliation: College of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang 212003, China.
authors.forename: Ling
authors.initials: L
authors.lastname: Wang
authors.affiliation: College of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang 212003, China.
authors.forename: Xiao-Li
authors.initials: XL
authors.lastname: Hu
authors.affiliation: College of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang 212003, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Cheng
authors.affiliation: College of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang 212003, China.
authors.forename: Kun
authors.initials: K
authors.lastname: Gao
mesh_terms: D001881:Borates / Q000633:toxicity*; D017377:Diatoms / Q000187:drug effects*; D007093:Imidazoles / Q000633:toxicity*; D052578:Ionic Liquids / Q000633:toxicity*; D008315:Malondialdehyde / Q000378:metabolism; D010544:Peroxidases / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism; D013482:Superoxide Dismutase / Q000378:metabolism; D018675:Toxicity Tests
chemical_list: C535268:1-dodecyl-3-methylimidazolium tetrafluoroborate; D001881:Borates; D007093:Imidazoles; D052578:Ionic Liquids; D017382:Reactive Oxygen Species; D008315:Malondialdehyde; D010544:Peroxidases; D013482:Superoxide Dismutase
keywords: 1-dodecyl-3-methylimidazolium tetrafluoroborate; Antioxidant enzymes; Ionic liquid; Phaeodactylum tricornutum; Photosynthetic activity