Study on the structure of a cytotoxic fucoidan from brown seaweed sargassum swartzii by tandem mass spectrometry

Abstract

We reported a study of the structure of cytotoxic fucoidan fraction extracted from brown

seaweed Sargassum swartzii by using NMR and tandem mass spectrometry in combination with a Pascal software program. Fucoidan F-20 is composed mainly of fucose, accompanied by other monosaccharids (mostly Gal, but also Glc, Rha and Xyl), and significant amount of uronic acids and sulfate. MSIMS analysis showed the cytotoxic fucoidan F-20 has linear sequences of hexose-disulfated fucose-sulfated fucose-hexose. The fucoidan structure is chracterized by the branch of two glucuronic acid units linked to the hexose unit and fucose to the sulfated fucose.