Isolation and Structure of Biologically Active Glycosphingolipids from the Sea Cucumber Cucumaria echinata

✍ Scribed by Koji Yamada; Eiji Hara; Tomofumi Miyamoto; Ryuichi Higuchi; Ryuichi Isobe; Seiichiroh Honda

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 680 KB
• Volume: 1998
• Category: Article
• ISSN: 1434-193X
• DOI: 10.1002/(sici)1099-0690(199802)1998:2<371::aid-ejoc371>3.0.co;2-a

✦ Synopsis

Five cerebrosides,

CE-1-1, CE-1-2, CE-1-3, CE-3-1,

and

CE-

have been determined on the basis of chemical and spectroscopic evidence. The cerebrosides show lethality toward brine 3-2, and a ganglioside molecular species CG-1 have been obtained from the less polar and polar fractions, respectively, shrimps. On the other hand, the ganglioside CG-1 exhibits neuritogenic activity toward the rat pheochromocytoma cell of the chloroform/methanol extract of the sea cucumber Cucumaria echinata. The structures of these glycosphingolipids line, PC-12 cells.

Structure of the Cerebroside Molecular Species CE-1

A series of studies on the isolation and structure elucidation of the glycosphingolipids from sea cucumber species have been performed in our laboratory [1] [2] . In continuation CE-1 exhibits strong hydroxy and amide absorptions in of the preceding studies on the sea cucumber Pentacta ausits IR spectrum and a series of molecular ion peaks in the tralis, the isolation and characterization of the biologically positive FAB mass spectrum. In the 13 C-NMR spectrum, active glycosphingolipids from the sea cucumber Cucumaria the characteristic signals of a sphingosine-type cerebroside echinata (Gumi in Japanese) has now been conducted in possessing fatty acid and β-glucopyranose moieties are oborder to develop the novel medicinal resources from marine served (Scheme 1 and Table 1). Therefore, CE-1 must be a natural products. molecular species of a sphingosine-type cerebroside bearing Regarding the glycosphingolipid constituents of C. echisuch moieties. Furthermore, CE-1 is presumed to have nata, we have already described the isolation and structure mainly normal-type [3] fatty acids and branched-type [4] longdetermination of three sphingosine-type glucocerebroschain bases, since the carbon signals for the terminal methyl ides [1] . In this paper, we report on the isolation and characgroups are observed at δ ϭ 14.2 (normal form) and at δ ϭ terization of a further five glucocerebrosides as well as a 11.5 and 19.3 (branched form) in the 13 C-NMR spectrum ganglioside molecular species from the whole bodies of C. (Scheme 1 and Table 1).

echinata. The biological activities of the glycosphingolipids

The 1 H-NMR signals of the basic structure of CE-1 are also reported.

(Table 2) are in good agreement with those of the known The acetone-insoluble constituents, which were obtained cerebroside molecular species PA-0 [2] , which is composed of from the less polar fraction of the chloroform/methanol ex-(2S,3R,4E)-sphingosine, fatty acid, and β--glucopyranose tract of the whole bodies of C. echinata, were separated by subunits, and is a component of the related sea cucumber silica-gel column-chromatography to give two cerebroside Pentacta australis. In addition, the absolute configuration molecular species, CE-1 and CE-3. On the other hand, the of the glucose unit is verified as being of -form by means water-soluble lipid fraction of the extract was subjected to of the Hara method [5] . These results suggest that CE-1 has reversed-phase-followed by silica-gel column-chromatograthe same absolute configuration as that of PA-0 for the phy to give a ganglioside molecular species CG-1. Each of basic moiety at C-2, -3, -4, and -5, and for the glucopythese compounds moved as a single spot on normal-phase ranose (Scheme 1). (silica gel) TLC.

CE-1 undergoes methanolysis upon treatment with methanolic hydrochloric acid to yield a mixture of fatty acid [᭛] Part 5: See ref. [2] . methyl esters (FAM) and long-chain bases (LCB), together