(1991) Quilhot, Wanda; Sagredo, María Gloria; Campalans, Eliette; Hidalgo, María Eliana; Peña, Wenceslao; Fernández, Ernesto; Piovano, Marisa
Densitometric analysis (HPTLC) was used to determine the concentrations of phenolic metabolites in thalli of different age in Umbilicaria antarctica Frey et Lamb. Usnic acid and atranorin concentrations are highest in individuals of the youngest age class and decrease towards the oldest age classes, whereas gyrophoric acids is more abundant in intermediate age classes. Usnic acid and atranorin are present in isolated rhizines. The importance of the spatial distribution of atranorin and usnic acid in this species is discussed