12th International Conference on Harmful Algae

INTERNATIONAL SOCIETY FOR THE STUDY OF HARMFUL ALGAE12 th <strong>International</strong> <strong>Conference</strong> on Harmful Algae, Copenhagen, Denmark, 4-8 September 2006the Tunesian coast has beenisolated by high-performance liquidchromatography (HPLC), followingbioassay–guided fractionation of adichloromethane extract of shellfish.The identity and the purity of theisolated compounds were confirmedby liquid chromatography coupledwith tandem mass spectrometry(LC-MS-MS). According to its RF,its molecular mass and itsfragmentation patterns the toxinswere identified as a mixture ofgymnodimine A and gymnodimine Bat a concentration of 885 and 80.10 -6 mol /kg of shellfish,respectively. In contrast togymnodimine B, gymnodimine Aexhibited high neurotoxicity in miceand was lethal following inoculationby peripheral andintracerebroventricularadministration.PO.05-02Development of a highlysensitive determination methodfor cylindrospermopsin usingLC/ESI-MSSession: PO.05 - Toxin analysisSachiko KikuchiTohoku University, SENDAI, JapanCylindrospermopsin (CYN) is ahepatotoxic alkaloid produced byseveral freshwater cyanobacteriaincluding Cylindrospermopsisraciborskii. CYN-producingcyanobacteria are abundant insurface waters used as drinkingwater reservoirs throughout theworld. The toxicity of CYN and itspresence have prompted the WorldHealth Organization guideline valuefor drinking water quality of 1.0 µgCYN/L. When the guideline value isdetermined, a highly sensitivedetermination method is imperative.In this study, a highly sensitivedetermination method wasdeveloped, using LC/ESI-MS, andHEPES (2-[4-(2-Hydroxyethyl)-1-piperazinyl] ethane-sulfonic acid) asthe internal standard. In the LC/ESI-MS, the retention times of CYN andHEPES were 12.41 and 14.21 min,and were observed at m/z 414.00for CYN and 237.00 for HEPES,respectively. CYN was determinedfrom peak area ratios in theselected ion monitor (SIM) mode ofm/z 414.00/237.00. Linearity of thismethod was observed in the rangeof 0.05-25 µmol/L (0.1-52 ng/5 µlinjected volume). The quantificationlimit (QOL) at a signal-to-noise(S/N) ratio of 10 was 158 pg. Themethod is useful for determinationof CYN in environmental and/ordrinking waters.PO.10-14Ecological niche of a marine redtide ciliate Myrionecta rubrarevisited: multi-modes ofnutrition in a single speciesSession: PO.10 - Ecophysiology &AutecologyHS Kim 1 , G Myung 2 , KG Chang 2 , WYih 21 Ministry of Marine Affairs and Fisheries,KUNSAN, South Korea2 Kunsan National University, KUNSAN,South KoreaMyrionecta rubra Jankowski 1976(=Mesodinium rubrum Lohmann1908) is a marine kleptoplastidic(=retaining plastids of donor cells)ciliate feeding on cryptophytespecies including Teleaulax sp. Asa functional primary producer M.rubra is very common and oftencauses recurrent red tides in diverseeutrophic marine environments.Recently, we observed activebacterivory by M. rubra MR-MAL01strain that had been isolated fromGomso Bay, Korea. Thus, the204