Analysis of the polysaccharides from Cladophora falklandica. Some aspects of their action on the haemostatic system

ARATA PX; RAFFO, MP; QUINTANA I; CIANCIA M

Bali

Simposio; 21st International Seaweed Symposium; 2013

International seaweed asociation. Universitas Bakrie

Seaweeds from the Cladophorales synthesize sulfated xyloarabinogalactans. Those from C. rupestris have 3-linked b-D-galactose units sulfated on C-6, while the arabinopyranose units are 4-linked and sulfated on C-3. Besides, ramifications of single stubs of galactose and b-D-xylopyranose, as well as 4-linked xylose disaccharide ramifications were also present [1]. C. falklandica was collected in the high intertidal zone of protected wave-cut platforms composed by siltstone at Punta Este (42º 46´ 48´´ S, 64º 57´ W; Patagonia, Argentina) in September 2010. This species is extensively distributed along the Patagonian coast from 42° to 54°S. The room-temperature (CX1-CX3, 19.2 % of the milled seaweed), and 90º (CC1-CC3, 10.0 %) water extracts have galactose and arabinose as major sugars and similar quantities of xylose (11.5-7.7 %). However, while in CX1, CC2 and CC3, galactose is the major monosaccharide constituent, in the other samples, arabinose predominates. Percentage of sulfate decreases during the extraction sequence (27.3-15.4 %, expressed as SO3Na). No uronic acids were present, and only minor amounts of pyruvic acid were found. Anticoagulant properties of the extracts were evaluated using PT, APTT and TT. APTT and TT were prolonged by all the extracts, in a dose dependent manner. The most powerful effect was observed in the APTT test by CX2 suggesting that it may affect the intrinsic and/or common pathway of coagulation. However, its behavior in tests involving direct studies on the fibrin network formation gave opposite results. The lagtime of the fibrinformation was inversely proportional to the concentration, and the maximum velocity strongly increased with concentration of CX2. These latest results indicate a procoagulant activity. We are currently trying to interpret this, since both methods reflect the conversion of fibrinogen to fibrin but they are also sensitive to the presence of inhibitors that may be present in plasma.