title: Chemical characterisation of three haemolytic compounds from the microalgal species Fibrocapsa japonica (Raphidophyceae).
abstract: The molecular structures of the three main haemolytic compounds (Fj1, Fj2 and Fj3) isolated from the ichthyotoxic microalgal species Fibrocapsa japonica have been investigated by NMR, LC-ESI-MS, ESI-MS-MS, IR, GC-MS and GC-HRMS methods. They are polyunsaturated fatty acids which we identified as: 6,9,12,15-octadecatetraenoic acid (OTA, C18:4omega3), 5,8,11,14,17-eicosapentaenoic acid (EPA, C20:5omega3) and 5,8,11,14-eicosatetraenoic acid (arachidonic acid AA, C20:4omega6). The identity of the latter two was confirmed on the basis of commercial standards (C20:5omega3 and C20:4omega6). Both displayed the same spectroscopic and chromatographic characteristics as Fj2 and Fj3 and had a similar strong haemolytic effect. We propose that when F. japonica cells accumulate in fish gills during blooms these compounds could be the cause of icthyotoxicity.
authors.affiliation: Research Centre Terramare, Schleusenstasse 1, 26382 Wilhelmshaven, Germany. meng.fu@terramare.de
authors.forename: Meng
authors.initials: M
authors.lastname: Fu
authors.forename: Albert
authors.initials: A
authors.lastname: Koulman
authors.forename: Marion
authors.initials: M
authors.lastname: van Rijssel
authors.forename: Arne
authors.initials: A
authors.lastname: Lützen
authors.forename: M Karin
authors.initials: MK
authors.lastname: de Boer
authors.forename: Monika R
authors.initials: MR
authors.lastname: Tyl
authors.forename: Gerd
authors.initials: G
authors.lastname: Liebezeit
mesh_terms: D002851:Chromatography, High Pressure Liquid; D056890:Eukaryota / Q000737:chemistry*; D005231:Fatty Acids, Unsaturated / Q000737:chemistry*; D008401:Gas Chromatography-Mass Spectrometry; D006461:Hemolysis; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D019265:Spectroscopy, Near-Infrared
chemical_list: D005231:Fatty Acids, Unsaturated