Structural features of biologically active polysaccharide fractions from the leaves and seeds of Plantago major L.

Abstract

The leaves of Plantago major L. have been used as a wound healing remedy for centuries in many parts of the world. Polysaccharide fractions have been isolated from the leaves and screened for biological activity using the test for anti-complementary activity [1]. Fractions PMIa and PMII which were isolated from the 50(C water extract had high anti-complementary activity, and both fractions were subjected to structural analysis. PMIa was an arabinogalactan type II [2] and PMII was a pectin that contained both smooth and hairy regions [3-5]. Structure-activity studies showed that the ramified region PVa was the part of PMII that had the highest anti-complementary activity [4]. Polysaccharide fractions that contained acidic heteroxylans with anti-complementary activity have been isolated from the seeds [6]. The heteroxylans contained xylan backbones that were composed of blocks of (1→3)-linked residues and blocks of (1→4)-linked residues. Short side chains of single arabinose and xylose residues, Araf-( l→3)-Xylp and GlcpA-( l→3)Araf were linked to O-2 or O-3 of (1→4)-linked Xylp residues in the backbone [6, 7]