The Study On Preparation And Antithrombotic Activity Of Fucoidan Extracted From Scytosiphon Lomentaria

Fucoidan is a water soluble heteroglycan containing sulfate, which is a specialchemical component. The chemical composition and structure of fucoidan changewith different algae species, growth seasons and extraction methods.Priviousresearches found that fucoidan show unique eiffciency in medicine，it has theactivities of anticoagulants antithrombotic> antitumer> anti-HIV> improving immunityand Hypolipidemic bioactivities, which the phytocompounds can’t compare with.And the chemical properties of the fucoidan, especially its molecular weight, thecontent of the sulfate and fucose have a deep effect on bioactivities, so today itbecomes an emphasis of the natural medicine and marine medicine.There are somany researches on bioactivites of fucoidan from Ascophyllum nodosum,Fucus、Laminaria japonica> Sargassum thunbergii at present time, but there is nearly a virginarea in studying fucoidan extracted from Scytosiphon Lomentaria.The number of people dying from cardiovascular disease comes up to40.7%of the total deaths every year in China. The proportion is much higher than any othercauses of death, including cancer. Thrombosis is largely the result of cardiovasculardisease.Therefore，the development of natural antithrombotic drugs with higheiffcient but no side effects becomes the research emphasis in the world today，so thestudy on antithrombotic activity of fucoidan extracted from Scytosiphon Lomentariahas important realism meaning, in this paper, Scytosiphon Lomentaria on the TuojiIsland of Shandong Province is as raw material,sudied from four main aspects.The mainresults are as follows:1. The analysis on the basic nutrients of Scytosiphon Lomentaria shows that itis a kind of natural resources as good and healthy food，which is high in protein, lowin fat and rich in ash. Cr、Cu、Pb are not detected, showing that ScytosiphonLomentaria is as food of high security.The proportion between essential amino acids and non-essential amino acids in all kinds of amino acids is reasonable and flavoramino acid is high. It contains three kinds of saturated fatty acids and three kinds ofpolyunsaturated fatty acids,the proportion of linolenic acid and Eicosapentaenoicacid(EPA) are4.91%and10.99%，respectively.Polyunsaturated fatty acids of highproportion have good effect on the prevention and treatment of cardiovascular andcerebrovascular diseases.2.SLFC and SLFH are extracted from Scytosiphon Lomentaria by cold and hotwater extraction methods,，with high molecular weight and wide range of molecularweight distribution.Due to effect of hot water, Sulfate ion is removed partly? sulfatecontent in SLFC is higher than SLFH，different fucoidans are prepared by theQ-Sephrose FF anion column,determined on molecular weight> sulfate content andmonosaccharide composition of the main chemical indicators, suitable gradedelution concentration is found. SLFC1is prepared by sodium chloride solution of0.8mol/L eluting SLFC，SLFH1is prepared by sodium chloride solution of0.4mol/Leluting SLFH.After eluted, molecular weight of SLFC1and SLFH1becomes lowersigniifcantly, the range of molecular weight distribution becomes narrower，puritygets higher. The sulfate content in SLFC land SLFH1is higher than SLFC and SLFH.It is widely reported that sulfate content and the molecular weight are critical factorsthat affect antithrombotic activity.3.In this paper，SLFC、SLFC1、SLFH and SLFH1are studied on antithromboticactivity test, with the choice of DC stimulation-induced carotid artery thrombosismodel.the results are as follows: Direct current stimulation can cause rats’ carotidartery thrombosis, increase TXB2level in plasma extremely and reduce the contentof6-keto-PGFla very signiifcantly， DC stimulation can cause thrombosis byactivating platelets and promoting platelet aggregation, proliferating endothelialcells，SLFC1can prolong the whole occlusion time of carotid artery thrombusextremely at low and high doses,decrease TXB2content and increase content of6-keto-PGFla signiifcantly,showing high antithrombotic activity through inhibitingplatelet aggregation and promoting the secretion of6-keto-PGFl of endothelial cells.SLFC、SLFH、SLFH1can prolong the whole occlusion time of carotid arterythrombus extremely at high dose and not at low dose.SLFC and SLFH can reducethe content of TXB2signiifcantly but have little effect on the content of the6-keto-PGFla，showing great effect on platelets and vascular endothelial cells.4. The performance in anticoagulant experiment of four fiicoidans is nearlysame with the anti-thrombotic activity test， SLFC1can prolong APTT and TTsigniifcantly at low and high doses，but has little effect on PT、FIB and AT III，showing that it inhibits coagulation reaction by playing a role in the intrinsiccoagulation pathway. SLFC and SLFH can only prolong APTT and TT signiifcantlyat high dose，but have little effect on PT、FIB and AT III at low and high dose.SLFH1can prolong APTT signiifcantly and increase content of FIB at high dose，buthave little effect on TT、PT、FIB and ATIII.In summary, fiicoidans from Scytosiphon Lomentaria have good antithromboticand anticoagulant activity,providing a theoretical base for developing newantihrombotic medicine.There needs a further study on profound processing andhigh-value utilization of Scytosiphon Lomentaria.