Anticoagulant and antithrombotic effects of chemically sulfated fucogalactan and citrus pectin

Citrus pectin (CP14) from Citrus sinensis, and a fucogalactan (E) and a glucan (G16) from Agaricus bisporus were isolated and structurally characterized. CP14 was constituted by (1→4)-linked α-d-GalpA units, E was composed by a (1→6)-linked α-d-Galp main-chain, partially substituted at O-2 by non-reducing end-units of α-l-Fucp or α-d-Galp, and partially methylated at O-3, whereas G16 was composed of (1→6)-linked β-d-Glcp units. The polysaccharides were sulfated giving rise to CP14S, ESL and G16S. The APTT and PT assays showed a decreasing order of anticoagulant activity for ESL, CP14S and G16S, respectively. ESL and CP14S showed greater anticoagulant activity. However, ESL reduced thrombus formation to 32.3% at a dose of 6.0 mg kg−1, whereas CP14S inhibited totally the thrombus formation at 3.0 mg kg−1, in vivo. NMR and methylation analyses showed that α-d-GalAp units of CP14S were sulfated in 2,3-O-position, whereas ESL was mainly sulfated in 2-O-, 2,3-O- and 2,3,4-O-positions.