Three new species of Cladonia (Cladoniaceae, Ascomycota) from Southern Brazil.

Cladonia maculata, C. paranaensis and C. quiririensis are described as new to science.

Chemical structure and selected biological properties of a glucomannan from the lichenized fungus Heterodermia obscurata.

Successive aqueous and alkaline extraction of the thallus of the lichenized fungus Heterodermia obscurata provided a highly branched glucomannan fraction (GM), whose chemical structure was determined. This was based on monosaccharide composition, methylation, partial acid hydrolysis, and NMR spectroscopic analysis. It consisted of a main chain of (1→6)-linked α-D-mannopyranosyl units, almost all being substituted at O-2 with α-D-glucopyranosyl, α-D-mannopyranosyl, and 4-O-substituted α-D-mannopyranosyl groups.

Chemotypes significance of lichenized fungi by structural characterization of heteropolysaccharides from the genera Parmotrema and Rimelia.

Galactoglucomannans were isolated from the lichenized fungi of the genus Parmotrema (Parmotrema austrosinense, Parmotrema delicatulum, Parmotrema mantiqueirense, Parmotrema schindlerii, and Parmotrema tinctorum and that of Rimelia (Rimelia cetrata and Rimelia reticulata) via successive hot alkaline extraction and precipitation with Fehling solution. The structure of each polysaccharide was investigated using 13C NMR and HSQC-DEPT spectroscopy, methylation analysis, and HPSEC-MALLS. The galactoglucomannans had a (1-->6)-linked main chain of alpha-Manp units, substituted preferentially at O-2 and O-4 by alpha-Galp and beta-Galp nonreducing end-units, respectively.

Glucans of lichenized fungi: significance for taxonomy of the genera Parmotrema and Rimelia.

The glucans of lichenized fungi are an important class of polysaccharides with structural and chemotaxonomic roles. The water-insoluble glucans of the genus Parmotrema (P. austrosinense, P.