Screening and isolation of glyceroglycolipids with antialgal activity from several marine macroalgae

Glyceroglycolipids and antialgal activity were used as the main indexes to identify the glyceroglycolipid extracts of marine macroalgae with significant antialgal activity from 6 species of marine macroalgae—Codium fragile, Neoporphyra haitanensis, Sargassum fusiforme, Saccharina japonica, Silvetia siliquosa and Undaria pinnatifida. The extracts of all tested algae contained glyceroglycolipids and exhibited antialgal activity against Karenia mikimotoi and Phaeocystis globosa. Further, by antialgal activity bioassay-guided fractionation method in combination with extraction and partitioning as well as multi-chromatography, two glyceroglycolipids with antialgal activity, 1-O-palmitoyl-3-O-β-D-galactopyranosyl glycerol and 1-O-palmitoyl-2-O-oleoyl-3-O-β-D-galactopyranosyl glycerol, were isolated for the first time from N. haitanensis and S. siliquosa, respectively. There were no glyceroglycolipids with antialgal activity in the other four macroalgae.