Chemical structure and anticoagulant activity of highly pyruvylated sulfated galactans from tropical green seaweeds of the order Bryopsidales

PAULA X. ARATA; IRENE QUINTANA; DILSIA CANELON; BEATRIZ E. VERA; REINALDO COMPAGNONE; MARINA CIANCIA

CARBOHYDRATE POLYMERS

ELSEVIER SCI LTD

Lugar: Amsterdam; Año: 2015 vol. 122 p. 176 - 186

0144-8617

Sulfated and pyruvylated galactans were isolated from three tropical species ofthe Bryopsidales, Penicillus capitatus, Udotea flabellum, and Halimeda opuntia. They represent the only important sulfated polysaccharides present in the cell walls of these highly calcified seaweeds of the suborder Halimedineae. Their structural features were studied by chemical analyses and NMR spectroscopy. Their backbone comprises 3-, 6-, and 3,6-linkages, constituted by major amounts of 3-linked 4,6-O-(1 -carboxy)ethylidene-dgalactopyranose units in part sulfated on C-2. Sulfation on C-2 was not found in galactans from other seaweeds of this order. In addition, a complex sulfation pattern, comprising also 4-, 6-, and 4,6-disulfated galactose units was found.Afraction from P. capitatus, F1, showed a moderate anticoagulant activity, evaluated by general coagulation tests and also kinetics of fibrin formation was assayed. Besides, preliminary results suggest that one of the possible mechanisms involved is direct thrombin inhibition.