Effects of extraction condition on structural features and anticoagulant activity of F. vesca L. conjugates.

From the air-dried Wild strawberry (Fragaria vesca L., family Rosaceae) leaves five water-soluble glycoconjugates Fv I-V by different extraction conditions have been isolated. Effects of extraction steps/agents on chemical composition and anticoagulant activity of Fv I-V were examined. Dark brown F. vesca conjugates Fv I-V were recovered in 4.5-8.4% yields, based on dry herb. Isolates were composed of carbohydrate, phenolic and protein components. Fv I-V displayed on HPLC broad molecule-mass distribution patterns with dominance of low molecule-masses 9-14 kDa. Their carbohydrate parts revealed high hexuronic acids content (35-60%) while the dominant neutral sugars - galactose, arabinose and rhamnose were found in lower amounts and indicated the presence of rhamnogalacturonans associated with arabinogalactans in all F. vesca preparations. In all Fv I-V isolates high polyphenolic contents were determined, whereas proteins were found in low amounts only. In in vitro experiments on human pooled plasma Fv I-V showed at higher concentrations complete inhibition of plasma clot formation and the most active conjugates in aPTT, PT and TT tests were shown to be Fv I and Fv III, containing the highest amounts of phenolics.