Isolation of fucoxanthin from edible brown algae by microwave-assisted extraction coupled with high-speed countercurrent chromatography

A rapid and efficient method for the separation and purification of fucoxanthin from edible brown algae by microwave‐assisted extraction coupled with high‐speed countercurrent chromatography was developed. The algae were first extracted using microwave‐assisted extraction, then the dried extract was dissolved and directly introduced into the high‐speed countercurrent chromatography system with a two‐phase solvent system consisting of hexane‐ethyl acetate‐ethanol‐water (5:5:6:4, v/v/v/v). The isolation was done in less than 75 min, and a total of 0.83 mg, 1.09 mg, and 0.20 mg fucoxanthin were obtained from 25.0 g fresh Laminaria japonica Aresch, 1.5 g dry Undaria pinnatifida (Harv) Sur, and 15.0 g dry Sargassum fusiforme (Harv) Setch, respectively. The purity of fucoxanthin determined by HPLC was over 90% and its structure was further identified by LC‐ESI‐MS and 1H‐NMR.