The occurrence of lichen phenolics in the photobiont cells of Evernia prunastri.

Photobiont cells of Evernia prunastri were isolated by filtration through a bed of Sepharose 2B. Algal preparations did not contain fungal contamination, as revealed by the absence of mannitol. Isolated photobionts contain the four Evernia phenolics, although repeated superficial washes with polyvinylpyrrolidone remove from these cells 81% atranorin, 51% chloroatranorin, 94% evernic acid and 82% usnic acid.