| The chain-forming dinoflagellate Gymnodinium catenatum was only one species in Gymnodinoid known that produces paralytic shellfish poison which had a negative impact on marin environment,aquaculture and human health.In this paper,the growth and toxin production of Gymnodinium catenatum were investigated.The effects of temperature,salinity and nutrients(N,P,Mn,Fe) on the growth and toxin production of the algae were discussed.The results of experiment showed that G.catenatum Hongkong strain could produce paralytic shellfish toxins and the toxic prolifes included DcSTX,B1, dcGTX3,dcGTX2 and C-toxin(C1,C2).The effect of temperature on the growth of Gymnodinium catenatum was significantly,and the optimal temperature was 25℃.The effect of salinity on the growth of Gymnodinium catenatum was also remarkable,and the optimal salinity for growth was 28.The toxicity of Gymnodinium catenatum increased when salinity increased at 15℃and 20℃,but declined as salinity increased at 25℃.In the toxin profiles of Gymnodinium catenatum,the mol%of C1 increased and the mol%of dcSTX decreased when temperature raise,the changes of other toxin profiles were limited when temperature varied.The effect of salinity on mol%of toxin profiles was litter.The highest cell densities of Gymnodinium catenatum increased when N,P concentrations increased at 25℃,and there were no significant changes in different Mn and Fe concentrations.The highest toxicity of Gymnodinium catenatum was 23.57 pg STX Equal/cell and the lowest toxicity was 0.47 pg STX Equal/cell. Temperture and concentrations of nutrients(N,P,Mn,Fe) had a great effect on the toxicity of Gymnodinium catenatum,Insufficient of nitrogen or phosphorus was advantageous to the cell toxin synthesis in the culture condition of lower temperature. The content of toxin in the cell could increase in the condition of lower Mn or higher Fe concentrations and optimal temperature.
|
PDF Full Text Request