Constituents of Holothuroidea, 13. Structure of neuritogenic active ganglioside molecular species from the sea cucumber Stichopus chloronotus

Three ganglioside molecular species, SCG-1, SCG-2, and SCG-3, were obtained from the lipid fraction of the chloroform-methanol extract of the sea cucumber Stichopus chloronotus. On the basis of chemical and spectroscopic evidence, the structures of these gangliosides have been determined to be 1-O-[(N-glycolyl- α-D-neuraminosyl)-(2→6)-β-D-glucopyranosyl]-ceramide (SCG-1), 1-O-[8-O-sulfo(major)-(N-acetyl-α-D-neuraminosyl)-(2→6) -β-D-glucopyranosyl]-ceramide (SCG-2), and 1-O-[α-L-fucopyranosyl- (1→11)-(N-glycolyl-α-D-neuraminosyl)-(2→6)-β-D- glucopyranosyl]-ceramide (SCG-3). The ceramide moieties were composed of heterogeneous long-chain base and fatty acid units. SCG-3 is the first type of ganglioside containing a fucopyranose in the sialosyl trisaccharide moiety. Moreover, these three gangliosides exhibited neuritogenic activity toward the rat pheochromocytoma PC12 cells in the presence of nerve growth factor.