Survey Of Pollution And Depuration Of Patinopecten Yessoensis In Dalian

In this paper,through investigation,testing and experimental verification technologies to learn biological fouling conditions of shellfish in north China.Patinopecten yessoensis,as the research object,were used to find the method of cutting down the Bacterial contamination,heavy metal pollution and shellfish poison.After exposure to Escherichia coli,the accumulation and tissue distribution of E.coli in Patinopecten yessoensis was studied.Meanwhile,taking the E.coli level as a parameter index,an experiment was designed to determine several key factors influencing the aseptic sea water depuration of Patinopecten yessoensis by ozone.Furthermore,the changes in nutrient composition in Patinopecten yessoensis were assayed during the depuration.The result showed that the level of E.coli forms throughout the tissues of the Patinopecten yessoensis exhibited the following orders:digestive tract>gonad>gills and labial palps>muscles.The optimal depuration condition was obtained as follows:scallop weight to water weight is 1:8,salinity is 33,depuration time is 32 h.It indicated that the nutritious constituents of the Patinopecten yessoensis samples were hardly influenced by the depuration process.This study demonstrated the ozone depuration method could not only reduce Patinopecten yessoensis microbiological contaminations,but also could retain its nutrition.The pollution of paralytic shellfish poison(PSP)was investigated in economic shellfish samples collected from May 2007 to December 2008 in the Changhai's sea area by the mouse bioassay method,meanwhile,testing the PSP in Patinopecten yessoensis.The result showed that the concentrations of PSP throughout the shellfishes were as follow:Patinopecten yessoensis>Saxidomus purpuratus>Neptunea cumingi>abalone.Patinopecten yessoensis was the main contaminated species in Changhai's sea area.It's PSP concent was changed with the seasons.Most contamination took place in spring and summer,while the least in fall and winter;The Patinopecten yessoensis was fed for 50 days at 6? seawater,and the concent of PSP from 20.94Mu/g down to 3.49Mu/g.Changes in salinity will affect the general shape of metal and the interaction between metals,thus affecting the bioavailability of metals.In this paper,Patinopecten yessoensis were applied in high-salinity conditions,the results showed that high-salinity condition impedes the exclusion of cadmium.