title: Accumulation of petroleum hydrocarbons in intracellular lipid bodies of the freshwater diatom Synedra acus subsp. radians.
abstract: The accumulation of hydrophobic compounds by phytoplankton plays a crucial role in the biogeochemical cycle of persistent organic pollutants (POPs) in aquatic environments. We studied the accumulation of polycyclic aromatic hydrocarbons (PAHs) in the freshwater diatom Synedra acus subsp. radians during its cultivation with crude oil hydrocarbons, using epifluorescent and laser confocal microscopy as well as gas chromatography-mass spectrometry (GC/MS) analysis. Our results revealed that in the presence of crude oil or an extract of a crude oil/n-hexane solution (light oil), S. acus subsp. radians accumulated PAHs in its lipid bodies. During cultivation in the presence of a crude oil/n-hexane solution, the cells selectively accumulated C12-C18 alkanes, with a preference for C15 and C16 homologues. The length of n-alkane hydrocarbon chains accumulated in cells was similar to the acyl chains of fatty acids of the diatom. We therefore suggest that the insertion of n-alkanes into the membrane lipid bilayer promotes the transmembrane transport of PAH in diatoms. Our results confirm the hypothesis that diatoms play a role in the elimination of hydrophobic hydrocarbons from aquatic systems.
authors.affiliation: Limnological Institute, Siberian Branch, Russian Academy of Sciences, 3 Ulan-Batorskaya, 664033, Irkutsk, Russia. sershilin@gmail.com.
authors.forename: Sergey M
authors.initials: SM
authors.lastname: Shishlyannikov
authors.affiliation: Limnological Institute, Siberian Branch, Russian Academy of Sciences, 3 Ulan-Batorskaya, 664033, Irkutsk, Russia.
authors.forename: Alyona A
authors.initials: AA
authors.lastname: Nikonova
authors.affiliation: Limnological Institute, Siberian Branch, Russian Academy of Sciences, 3 Ulan-Batorskaya, 664033, Irkutsk, Russia.
authors.forename: Igor V
authors.initials: IV
authors.lastname: Klimenkov
authors.affiliation: Limnological Institute, Siberian Branch, Russian Academy of Sciences, 3 Ulan-Batorskaya, 664033, Irkutsk, Russia.
authors.forename: Alexander G
authors.initials: AG
authors.lastname: Gorshkov
mesh_terms: D000473:Alkanes / Q000032:analysis / Q000378:metabolism; D000818:Animals; D017377:Diatoms / Q000737:chemistry* / Q000378:metabolism; D005618:Fresh Water / Q000032:analysis; D008401:Gas Chromatography-Mass Spectrometry; D006838:Hydrocarbons / Q000032:analysis* / Q000378:metabolism; D066292:Lipid Droplets / Q000737:chemistry* / Q000378:metabolism; D018613:Microscopy, Confocal; D008856:Microscopy, Fluorescence; D008962:Models, Theoretical; D010578:Petroleum / Q000032:analysis* / Q000378:metabolism; D010839:Phytoplankton / Q000737:chemistry / Q000378:metabolism; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis / Q000378:metabolism; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000378:metabolism
chemical_list: D000473:Alkanes; D006838:Hydrocarbons; D010578:Petroleum; D011084:Polycyclic Aromatic Hydrocarbons; D014874:Water Pollutants, Chemical
keywords: Accumulation; Diatom; Lake Baikal; Lipid bodies; PAH; Synedra acus subsp. radians