Search for Bioactive Substances from Marine Algae

The biological activity of water extracts from 29 species of marine algae was investigated and some extracts from the seaweeds were found to possess potential as medical agents. Three extracts showed antitumor effect on B-16 melanoma cells transplanted subcutaneously in mice. One of these extracts, Amphiroa aberrans, in particular, showed high activity (77.4%). Extract of Sargassum patens, S. micracanthum, Gelidium amansii, Gloiophloea okamurai and Gloiopeltis furcata induced the formation of antitumor factors against L929 cells from human HL-60 and murine macrophage hybridoma (MφH) MH6E11 cells. Extracts of S. kjellmanianum, G. amansii and Grateloupia elliptica suppressed the production of these factors in MH6E11 cells activated by lipopolysaccharide. TNF inhibits lipoprotein lipase. Extracts from Ishige okamurai, reverse this inhibition. Six seaweed extracts (3 brown, and 3 red algae) suppressed the thymus cells. Three of them, S. kjellmanianum, G. amansii and G. elliptica, suppressed the activation of MφH, in addition to inhibitioning thymus cell proliferation