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Item Los líquenes de isla Navarino. I: Estudio sistemático y ecológico preliminar(1977) Redon, Jorge; Quilhot, WandaA preliminary account is presented on the lichen flora of Navarino Island (Magallanes Province, Chile). The result given are: 1) a list of the 56 lichen species; 2) a vegetational profil between Ukika beach (O m) and a mountain (600 m.) south of Ukika; 3) a discussion about the phytogeographical relations on this lichen flora, specially in connection with the antarctic lichen flora; 4) a review of the most typical communities.Item Posible rol biológico de metabolitos secundarios en líquenes antárticos(1992) Quilhot, Wanda; Hidalgo, María; Fernández, Ernesto; Peña, Wenceslao; Flores, EvaLos productos secundarios de líquenes tendrían un rol adaptativo en especies que desarrollan su ciclo de vida en climas rigurosos. Se discuten los roles probables: filtros de la radiación ultravioleta, transferencia de energía a los pigmentos fotosintéticos y reservas energéticas a utilizar en períodos de déficit de nutrientes.Item Quantitative variations of phenolic compounds related to thallus age in Umbilicaria antarctica(1991) Quilhot, Wanda; Sagredo, María Gloria; Campalans, Eliette; Hidalgo, María Eliana; Peña, Wenceslao; Fernández, Ernesto; Piovano, MarisaDensitometric 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 discussedItem Boletín Antártico Chileno(1995-11) Lizasoain, Sergio; Cavieres, Fernanda; Fernández, Ernesto; Jaña, Ricardo; Jeffries, Martin; Müller, Rolf; Pannatier, Serge; Torres, Daniel; Quilhot, Wanda; Ramírez Aranda, Lucía; Rubio, Carlos; Reyes, Salvador; Vicuña, Patricia; Instituto Antártico Chileno; Ordóñez Kovacevic, Yasna; Ríos Villalón, Juan; Ramírez Aranda, Lucía; Torres, DanielItem Studies on Chilean lichens. XI Secondary metabolites from Antarctic lichens(1989) Quilhot, Wanda; Garbarino, Juan; Piovano, Marisa; Chamy, María Cristina; Gambaro, Vicente; Oyarzún, María Luisa; Vinet, Cindy; Hormaechea, Valeria; Fiedler, PeterThe major secondary metabolites of 17 Antarctic lichen species were studied via macroextraction. The most frequently found compounds were usnic acid and atranorin. Two polysubstituted depsides were isolated from Lecania brialmontii, brialmontins 1 and 2; from Catillaria corymbosa a derivative of hiascic acid was isolated, 2' -0-methylhiascic acid. Peroxyergosterol, a sterol infrequent in lichens, was found in four species.Item Temporal variation in usnic acid concentration in Usnea aurantiaco-atra (Jaq.) Bory(1991) Quilhot, Wanda; Peña, Wenceslao; Flores, Eva; Hidalgo, María Eliana; Fernández, Ernesto; Leighton, GerardoIn Usnea aurantiaco-atra (Jaq.) Bory, growing in the Antarctica, a monthly variation in the usnic acid content, in individual thalli, was studied by means of scanning densitometry (HPTLC). The higher accumulation rates were quantified from January to May; there was a significant decrease in the concentrations from June to December, during the three years of study. In spite of the thalli were taken from a same location, variations could be observed in the usnic acid concentration in the individuals from within each monthly sampleItem Studies on Chilean Lichens. XVI. Advances in the Chemistry of Secondary Metabolites from Antarctic Lichens(1991) Piovano, Marisa; Garbarino, Juan; Chamy, María Cristina; Zúñiga, Viviana; Miranda, Cecilia; Céspedes, Elsa; Fiedler, Peter; Quilhot, Wanda; Araya, GriseldaThe secondary metabolites of 12 species of Antarctic lichens belonging to various systematical groups hace been analyzed by macroextraction. The compounds were characterized by their physical and spectroscopic properties. Cladonia cornuta, C. lepidophora and Ochrolechia deceptionis were analyzed for the first time. Atranorin and usnic acid were the most frecuent lichen substances. The sterol ergosterol peroxide was isolated from all the species analyzedItem Preliminary data on the accumulation of usnic acid related to ozone depletion in two Antarctic lichens(1996) Quilhot, Wanda; Fernández, Ernesto; Rubio, Cecilia; Cavieres, M. Fernanda; Hidalgo, M. Eliana; Goddard, Marcela; Galloway, DavidThe absorbing properties of UV radiation of lichen phenols agree with their photoprotector capacity determined by in, vivo and in vitro methods. The photostability that characterizes these compounds makes it possible to study the relations between the UV absorbers and ozone levels in different time scales. Usnic acid is the most frequent UV-B absorber in antarctic lichens. In Neuropogon aurantiaco-ater (Jacq.) I. M . Lamb. and Ramalina terebrata Hook. et Tayl., collected in Antarctica over a period of 30 years, the highest concentrations ofusnic acid were observed when ozone diminished to critical values.Item The occurrence of gold in Usnea auratiaco-atra(1988) Quilhot, WandaIn Usnea auratiaco-atra (Jacq.) Bory, a lichen species collected in the Antarctica, the gold content was determined by the cupellation methods, 317 ppb and 1089 ppb dry weight were found in the lichen samples. A possible mechanism to explain the metal accumulation is discussed.Item Studies on Chilean Lichens. XXI. Secondary metabolites from the Antarctic species Hypogymnia lugubris(1993) Piovano, Marisa; Quilhot, Wanda; Chamy, María; Fiedler, Peter; Garbarino, JuanFrom Hypogymnia lugubris (Pers.) Krog, a lichen collected in Antarctica, atranorin, ergosterol peroxide, and physodic, physodalic, protocetraric and usnic acids were isolated.