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 2006Session: O.12 - Toxicology 2Presentation time: 16:40 - 17:00Guillaume Juhel 1 , J O'Halloran 1 , SCCulloty 1 , RM O'Riordan 1 , J Davenport 1 ,NM O'Brien 2 , KF James 3 , A Furey 3 , OAllis 31 University College Cork, CORK, Ireland2 2Department of Food Science, FoodTechno,, Ireland3 Cork Institute of Technology, CORK,IrelandThe Comet assay was used toinvestigate the potential ofmicrocystins to induce DNAdamage in the haemocytes of thefreshwater zebra mussel, Dreissenapolymorpha. Laboratory in vivoexposure experiments wereconducted over a 21-day periodwith three strains of thecyanobacterium Microcystisaeruginosa, with different toxicitiesand toxic profiles and one non-toxicstrain. Mussels were sampled at 0,7, 14 and 21 days. A positive controlwas performed with CdCl2-spikedwater.Cell viabilities were high throughoutthe study, demonstrating that themicrocystin doses were notcytotoxic. A clear dose-response inthe DNA damage was observedfollowing exposure to CdCl2,showing the sensitivity of themussels’ haemocytes. DNAdamage, measured as percentagetail DNA was observed with thethree toxic Microcystis strains butnot with the non-toxic strain. Toxicanalysis of the cyanobacterialcultures revealed the presence oftwo MC variants, MC-LF and MC-LR. The DNA damage observedappeared to be strain-specific andsimilar to a dose-response, showingthat MC-LF may have a highergenotoxicity than MC-LR. MC-LFalso seemed to induce morepersistent DNA damage than MC-LR. This study is the first todemonstrate that in vivo exposureto microcystins induces DNAdamage in the haemocytes of zebramussels.O.12-02Toxic effects of nodularin to thebrown alga Fucus vesiculosus inrelation to oxidative stressresponseSession: O.12 - Toxicology 2Presentation time: 17:00 - 17:20Stephan Pflugmacher 1 , Harri TKankaanpää 2 , Miika Olin 21 IGB, BERLIN, Germany2 Finish Institute of Marine Research,HELSINKI, FinlandThe cyclic pentapeptide nodularin(NOD) is produced by thecyanobacterium Nodulariaspumigena which regularly formheavy blooms in the Baltic Seaduring summer season. The mostcommon NOD congener is NOD-R,i.e. cyclo(-D-erythro-?-methylAsp(iso)-L-Arg-Adda-D-Glu(iso)-2-(methylamino)-2-(Z)-dehydrobutyric acid), where Addastands for 3-amino-9-methoxy-2,6,8-trimethyl-10-phenyldeca-4(E),6(E)-dienoic acid. Recentstudies have indicated thatcyanobacterial hepatotoxinsaccumulate to blue mussels andsome Baltic fish species, e.g.flounder (Platichthys flesus), Atlanticcod (Gadus morhua) and bluemussel (Mytilus edulis) andthreespine stickleback(Gasterosteus aculeatus). Acompartment of the marine costalecosystem which has been paidless attention is marine macroalgae.The uptake of toxin in F.vesiculosus, toxic response (lipidperoxidation) as well as theactivation of the antioxidative stressresponse (superoxide dismutase,55