HETEROPOLYSACCHARIDES OF THE LICHEN EVERNIA-PRUNASTRI

Extraction of Evernia plunastri with hot aqueous alkali solubilized he teropolysaccharide-containing material which was purified via Fehling precipitation. Further workup of this polysaccharide with Cetavlon gav e two fractions having related but different structures. Each structur e consisted of a 1 -->, 6-linked alpha-D-Man p main chain partially mo nosubstituted at O-2 with side chains of alpha-D-Gal p and partially d isubstituted at O-2 and O-4 with alpha-D-Gal p and beta-D-Gal p, respe ctively. The fractions differed in that one contained much more uronic acid than the other, with corresponding predominance of side chains c ontaining alpha-D-Glc p A-(1 --> 3)-D-Glc p, (alpha-D-Gal p-(1 -->, 2) -D-Glc p, and beta-D-Gal f units.