title: Carbohydrate, glycopeptide and protein components of the lichen Sticta sp. and effect of storage.
abstract: Three aldoses, six alditols, eight oligosaccharides, three polysaccharides and a glycopeptide were found in a Sticta sp. The most interesting of these were gentiobiose, -triose and -tetraose, O-alpha-D-Galp-(1-->6)-O-beta-D-Galp-(1-->1)-D-glyceritol released on alkaline treatment, and a polysaccharide with predominant (1-->4)-linked beta-D-Xylp units. Present were a galactoglucomannan, a polysaccharide, possibly a mixture, containing beta-D-Galf, and alpha-L-Araf units and a glycopeptide with alpha- and beta-D-Galf, Galp, Glcp and Manp units, having a core with successive (1-->2)-linked alpha-D-Manp residues substituted at O-3 with those of alpha-D-Galf. After four years storage of the lichen, the contents of the principal polyols, ribitol (0.86%), arabinitol (0.99%) and mannitol (2.50%) fell to practically zero, with the appearance of threitol (0.03%), xylitol (0.01%) and myo-inositol (0.03%). Also, the protein content fell from 34 to 18%. The most abundant amino acids were valine (10.5% of total) in fresh lichen and threonine (14.6%) in stored lichen.
authors.affiliation: Departamento de Bioquímica, Universidade Federal do Paraná, Curitiba-PR., Brazil.
authors.forename: M de L
authors.initials: Mde L
authors.lastname: da Silva
authors.forename: M
authors.initials: M
authors.lastname: Iacomini
authors.forename: E
authors.initials: E
authors.lastname: Jablonski
authors.forename: P A
authors.initials: PA
authors.lastname: Gorin
mesh_terms: D002240:Carbohydrate Sequence; D002241:Carbohydrates / Q000032:analysis*; D006020:Glycopeptides / Q000032:analysis*; D008011:Lichens / Q000737:chemistry*; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000032:analysis*; D011309:Preservation, Biological
chemical_list: D002241:Carbohydrates; D006020:Glycopeptides; D010940:Plant Proteins