Fucoxanthin as a Major Carotenoid in Isochrysis aff. galbana: Characterization of Extraction for Commercial Application

Fucoxanthin, a main marine carotenoid, in five species of fucoxanthin-containing microalgae, was quantified by high-performance liquid chromatography. Among the studied species, Isochrysis aff. galbana contained the highest amount of fucoxanthin (18.23 mg/g dried sample). This microalga showed good fucoxanthin extraction efficiency under the tested solvents (methanol, ethanol, acetone, and ethyl acetate), with the exception of n-hexane. In addition, most fucoxanthin (similar to 95%) could be extracted by a single extraction in ethanol within 5 min, and only 15% degradation of fucoxanthin was detected during ethanol extraction for 24 h. The two-phase solvent system of n-hexane-ethanol-water with a volume ratio of 10:9:1 was determined to be the best system for the separation of fucoxanthin and lipids from extracts of I. aff galbana. Under these conditions, fucoxanthin was fractionated in the hydroalcohol phase apart from the hexane phase containing lipids. These results imply that I. aff. galbana can be a commercial source for the spontaneous production of valuable fucoxanthins and lipids.