PRENYLLIPIDS AND PIGMENTS CONTENT IN SELECTED ANTARCTIC LICHENS AND MOSSES

The content and relative composition of tocopherols, plastochromanol, plastoquinone and pigments in fifteen Antarctic species (five mosses and ten lichens) were analyzed by HPLC. Total tocopherols in mosses ranged from 90 mu g/g (Warnstrofia sarmentosa) to 220 mu g/g (Syntrichia magellanica), while in lichens it ranged from 0.89 mu g/g in Caloplaca sp. to 45 mu g/g in Placopsis contortuplicata. With the exception of Ochrolechia frigida, in all other mosses and lichens species, a-tocopherol accounted for more than 90% of total tocopherols. Plastochromanol was detected in four mosses and two lichen species; the highest level was found in Polytrichastrum alpinum (19.1 mu g/g). The highest content of plastoquinone-9 (PQ-9) in mosses was found in Bryum pseudotriquetrum (42.6 mu g/g), whereas in lichens it was 24.5 mu g/g in Stereocaulon alpinum, and 23.17 mu g/g in Umbilicaria antarctica. Pigment composition in mosses was typical for higher plants. Some lichen species lacked chlorophyll b, violaxanthin and beta-carotene. Based on these results it is suggested that tocochromanols and carotenoid pigments are involved in the protection of mosses and lichens against the oxidative stress caused by the extreme Antarctic conditions.