Glucosylceramide Having a Novel Tri-Unsaturated Long-Chain Base from the Spermatozoa of the Starfish, Asterias amurensisi

抄録

Glucosylceramide (G1cβ1-1Cer) was isolated from the spermatozoa of the starfish, Asterias amurensis. The long-chain bases of the glycolipid consisted of dihydroxy (d18:2, d18:3, d19:3, and d22:2), and trihydroxy (t22:1) types. Long-chain aldehydes derived from them were analyzed mainly by proton nuclear-magnetic resonance to determine the detailed structures. Two of the tri-unsaturated bases were identified as (4E, 8E, 10E)-2-amino-4, 8, 10-octadecatriene-1, 3-diol (d18:3) and (4E, 8E, 10E)-2-amino-9-methyl-4, 8, 10-octa-decatriene-1, 3-diol (d19:3), which is a novel base. Both d22:2 and t22:1 had a cis double bond at the C9 or C13 position. All fatty acids were 2-hydroxylated (C₁₄-C₂₅):Most of themwere saturated and unbranched. About 10% was mono-unsaturated and unbranched (C₂₂-C₂₅), while saturated but branched (iso- and anteiso-types) C₁₅-C₁₈ acids were found as mi-nor components. The main fatty acids, which summed up to more than 93% of the fatty acids in the glucosylceramide, were n-14h: 0, n-15h:0, n-16h : 0, n-17h : 0, n-18h : 0, and n-24h:1.