Isolation and characterization of a novel uronic acid-containing acidic glycosphingolipid from the ascidian Halocynthia roretzi

A novel uronic acid-containing glycosphingolipid (UGL-1) was isolated from the ascidian Halocynthia roretzi. UGL-1 was prepared from chloroform-methanol extracts and purified by the use of successive column chromatography on DEAE-Sephadex, Florisil, and Iatrobeads. Chemical structural analysis was performed using methylation analysis, gas chromatography, gas chromatography-mass spectrometry, matrix-assisted laser-desorption/ionization time-of-flight mass spectrometry, and H-1-NMR spectra. The chemical structure of UGL-1 was determined to be a glucuronic acid-containing glycosphingolipid, Gal beta 1-4(Fuc alpha 1-3)GlcA beta 1-1Cer. The ceramide component was composed of C16:0 and C18:0 acids and C-16-, C-17-, and C-18-phytosphingosines as major components.