Michael Quilliam1, William Hardstaff1, Allan Cembella1, Don Richard2 and Shelly Hancock3
1NRC Institute for Marine Biosciences, 1411 Oxford St. Halifax, Nova Scotia B3H 3Z1; 2Canadian Food Inspection Agency, 343 University Avenue, Moncton, New Brunswick E1C 9B6; 3 Canadian Food Inspection Agency, 1992 Baffin St., Dartmouth, Nova Scotia B2Y 3Z7
Poster Abstract
Spirolides are biologically-active macrocyclic imines found in plankton and shellfish from the eastern coast of Nova Scotia, Canada. They appear in lipophilic extracts of shellfish and cause rapid death (3-20 min) upon intraperitoneal injection into mice, with apparent neurotoxic symptomology. Several of these toxins have been structurally characterized and the primary producer of the spirolides has been shown to be the marine dinoflagellate, Alexandrium ostenfeldii. A rapid liquid chromatography-mass spectrometry (LC-MS) method based on electrospray ionization has been established for the analysis of spirolides in plankton and shellfish samples. This method provides very high sensitivity (low picogram or ng/mL detection limit) and has allowed the detection of several new spirolides. Tandem mass spectrometry (MS-MS) provides structural information for the identification of such new compounds. Extraction methods for both shellfish and plankton have been developed. This includes a new micro-extraction procedure for rapid analysis of spirolides in pooled plankton cells individually isolated by micropipette or flow cytometry. Such techniques have allowed us to study the geographical and temporal distribution of spirolides in Nova Scotian waters, as well as the production of spirolides by an isolate of A. ostenfeldii grown in culture.