A 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 ...
Los 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 pe...
Secondary products produced by lichens are assumed to playa role in species that develop their life cycle under extreme conditions. A number of hypothesis concerning to their biological role -filters of ultraviolet radiation, energy transfers to the photosynthetic pigments, energetic sources to u...
En isla Decepción, Shetland del Sur, se aprovechan substratos producidos por erupciones volcánicas, de hace 147, 72 y 18 años, para describir la riqueza específica alcanzada por las taxocenosis de musgos y líquenes. Se trabajó en las áreas de monte Kirkwood, bahía Fumarola y bahía Teléfono, calet...
In Deception Island, South Shetland Islands, substrates origiriated during the volcanic eruptions that occurred 147, 72 and 18 years ago, were studied to determine the degree of advancement of their ecological succession , as was evidenced by the values of species richness in the communities of m...
En seis lugares de la península Ardley, isla Rey Jorge, se determinó la concentración supeificial y distribución vertical de 137Cs en el suelo y su acumulación en la cubierta vegetal de éste. La concentración superficial de I37Cs fluctuó entre 121 y 532 Bq m-2. Su gran variación en un área reduci...
137Cs areal concentration and vertical distribution were determined at six sites located on Ardley
Peninsula, King George lsland. The total 137Cs areal concentration ranges from 121 to 532 Bq m-2. Its high variation can be attributed to water runoff and soil erosiono A relatively high percentage ...
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 class...
In 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 c...
The 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 ...
Se estudiaron los metabolitos secundarios mayoritarios de 17 especies de líquenes antárticos mediante macroextracción. Los compuestos más frecuentes fueron el ácido úsnico y la atranorina. De Lecania brialmontii se aislaron dos interesantes dépsidos polisustituidos, la brialmontina 1 y la brialmo...
From Hypogymnia lugubris (Pers.) Krog, a lichen collected in Antarctica, atranorin, ergosterol peroxide, and physodic, physodalic, protocetraric and usnic acids were isolated.
De Hypogymnia lugubris (Pers.) Krog, un liquen recolectado en la Antártica, se aisló atranorina, peroxiergosterol y los ácidos fisódico, fisodálico, protocetrárico y úsnico.
The 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 ...
Los metabolitos secundarios de 12 especies de líquenes antárticos, pertenecientes a variados grupos sistemáticos, han sido analizados vía macroextracción. Los compuestos fueron caracterizados por medio de sus propiedades físicas y espectroscópicas. Cladonia cornuta, C. lepidophora y Ochrolechia d...
