Brown algae (Fucus spp.) from the Baltic Sea were extd. with supercrit. CO2 (i) with or (ii) without EtOH co-solvents at 40 degrees C under 300-900 bar on a pilot plant scale to recover biol. active compds. Extns. (i) were more effective than (ii) and resulted in increasing extn. efficiency (up to more than 5.1%).