Preparation of different molecular weights of sea cucumber fucoidan and study on their absorptive characteristics in rats

Objective To observe the absorptive characteristics of sea cucumber fucoidan(SC-FUC) with different molecular weights in rats.Methods Sea cucumber fucoidan with different molecular weights was prepared with enzymatic method.Twenty-four SD rats were randomly divided into 4 groups.Sea cucumber fucoidans with different molecular weights were orally administered at a dose of 1 000mg·kg-1.Blood samples were collected from tail vein at regular period after the administration.A high performance liquid chromatography with precolumn derivatization(PMP-HPLC) was used for the determination of the levels of serum fucose in rats.Results The molecular weights of SC-FUC prepared were 700,437.8,52.7 and 20.5 kD,which sulfate content range from 21.4% to 22.4%.After administration of SC-FUC,serum fucose levels increased in almost all rats.The serum fucose level reached the peak value(53~55 μg·mL-1) in 12~15 h in low molecular SC-FUC treated groups,while the serum fucose level reached the peak value(45 μg·mL-1) in 36 h in the high molecular SC-FUC treated groups.The serum fucose level restore to the initial after 48 h in all SC-FUC treatment rats.Conclusion SC-FUC can be absorbed by rats,while the bioavailability is different depended on molecular mass.Those results provide a test base for SC-FUC application,and will contribute to the development of sulfated polysaccharides drugs.