Dynamics Of Fatty Acids In Common Red-tide Algaes In The Jiaozhou Bay And Its Application

Global climate changes and deepening impacts of human beings on the oceans caused an increase in the coastal eutrophication and red-tides,which resulted in continuous declining in marine living resources.According to past records,more than 300 kinds of algaes triggered red-tides,of which more than 80 kinds of algaes can produce Phycotoxins . At present , most studies have focused on inhibition of Phycotoxins on marine zooplankton. However,nutrients of algaes,such as fatty acids especially polyunsaturated fatty acids(PUFA), play an irreplaceable role in the cell membrane,retina,brain,nerve tissue and some hormone.thus,they are vital for development and recruit of marine animals.During red-tides, biotic succession of dominant algae species and transformations of its developing phase will cause some changes in fatty acids which will bring about profound influence on zooplankton,even on the whole marine animals.From what we have discussed, it is obvious that phycotoxins is just one aspect to cause a decline in biological resource.This paper,from stand of nutrition,conducted a research on fatty acids of the common red-tides in the JiaoZhou Bay and the changing rule of its fatty acids along with growth phases.what's more,we also studied the impacts of this changes on marine zooplankton at the same time .This paper have analysed characteristic composition and changing regularity of fatty acids of the four red-tide algaes during growth phase by gas chromatography-mass spectrometry(GC/MS) technology,and investigated impacts of different growth phase of red-tide algae on copepod Calanus sinicus.In detection analysis,the datas such as linear correlation,recovery rates,precision,repeatability and so on,show the method of extraction,purication and examination of fatty acids reliable and accuracy.From selected 18 fatty acids:the saturated fatty acids C14:0,C16:0 are dominant,the main polyunsaturated fatty acids are C18:2ω6 , C20:5ω3 , without C22:6ω3 in diatom.Whereas in dinoflagellate,C16:0,C18:0,C18:2ω6,C18:3ω6,C22:6ω3 are primary.Observe that The ratio of C16:1ω7/C16:0 is obviously higher in diatom than in dinoflagellate.The general changing trend of fatty acids in growth stages of the red-tide algaes seems be that:from adaptative phase,the content increase gradually passing through logarithmic phase,the value get to the climax till stationary phase,and start to decrease as soon as decline phase coming.Further more,the present datas indicate: the logarithmic phase of rid-tide algaes which contain more fatty acids can make Calanus sinicus keep a degree of eggs production rate(EPR),however,the decline phase of rid-tide algaes were terminating its eggs production gradually in contrast.In both growth phase,dinoflagellate(Prorocentrum micans)containing more fatty acids,PUFA in particular,was preferable to diatom diets(Skeletonema costatum)for eggs production.