ISOLATION, CHEMICAL AND SPATIAL CHARACTERIZATION OF ACIDIC POLYSACCHARIDES FROM SOME PLANTS OF SIBERIAN FLORA WITH IMMUNOTROPIC ACTIVITY

Abstract

Plant polysaccharides have a wide range of biological activity, including an immunotropic effect, the degree and magnitude of which depends on the composition and tertiary structure of the macromolecule. Acidic polysaccharides (APS) were isolated by extraction with an acidic aqueous solution (pH=3) and characterized From the rhizomes of Acorus calamus L., the aerial part of Centaurea pseudomaculosa Dobrocz., the herb Conium maculatum L., and the leaves of Betula pendula Roth. The content of total carbohydrates was determined for all samples (>90%), uronic acids (24.56–53.70%) and a small amount of impurity substances (protein and nucleic acids 0.81–1.02% and 0.016–0.035%, respectively); molecular weight distribution (Mn, Mw). Structural features were studied using physicochemical and instrumental methods, such as UV and IR spectroscopy, reaction with Congo red, and scanning electron microscopy. The polysaccharides of Acorus calamus, Conium maculatum, and Betula pendula have a triple-helical conformation and bulky ultrastructure; the polysaccharides of Centaurea pseudomaculosa are characterized by the absence of a triple-helical conformation and an amorphous ultrastructure.