Supercritical CO2 extraction of fatty acids, phenolics and fucoxanthin from freeze-dried Sargassum muticum

The potential of compressed CO2 for the extraction of valuable compounds (fatty acids, phenolic compounds and fucoxanthin) from the brown alga, Sargassum muticum, has been explored. Pure supercritical CO2 (scCO(2)) allowed the extraction of up to 15 % of the ethanol extractables, with the highest yield attained at 10 MPa and 50 A degrees C. The addition of ethanol as cosolvent increased by three both the extraction yields and the radical scavenging activity, and by 90 times the fucoxanthin yield. The extracts obtained with pure carbon dioxide contained higher proportion of omega 3 fatty acids than those using with conventional solvents, showing an omega 6/omega 3 ratio of 2.12 and 2.84 for pure and ethanol modified scCO(2), respectively. Selected extracts showed antibrowning activity on B16F10 murine cells and inhibition of lipogenesis in SW872 liposarcoma cells, although cytotoxic effects were observed at 50 mu g mL(-1).