Characterization of a complex mixture of phytosphingosine-type ceramides from the tunisian Reaumuria vermiculata
Written by sctunisie no commentsThe aerial parts of Reaumuria vermiculata afforded a complex mixture of eight ceramides (C36H71O5 + nCH2 (n=0; 2 to 8)), previously identified in other natural sources and isolated for the first time from Reaumuria vermiculata (Tamaricaceae) : (2S, 3S, 4R, 2’R, 8E)-2-(2’-hydroxyoctadecanoylamino)-8-octadecen-1,3,4-triol (1), (2S, 3S, 4R, 2’R, 8E)-2-(2’-hydroxyeicosanoylamino)-8-octadecen-1,3,4-triol (2), (2S, 3S, 4R, 2’R, 8E)-2-(2’-hydroxyuneicosanoylamino)-8-octadecen-1,3,4-triol (3), (2S, 3S, 4R, 2’R, 8E)-2-(2’-hydroxydocosanoylamino)-8-octadecen-1,3,4-triol (4), (2S, 3S, 4R, 2’R, 8E)-2-(2’-hydroxytricosanoylamino)-8-octadecen-1,3,4-triol (5), (2S, 3S, 4R, 2’R, 8E)-2-(2’-hydroxytétracosanoylamino)-8-octadecen-1,3,4-triol (6), (2S, 3S, 4R, 2’R, 8E)-2-(2’-hydroxypentacosanoylamino)-8-octadecen-1,3,4-triol (7), (2S, 3S, 4R, 2’R, 8E)-2-(2’-hydroxyhexacosanoylamino)-8-octadecen-1,3,4-triol (8). The ceramides were characterized on the bases of spectroscopic and chemical evidences. The resulting mixture of hydroxy-fatty acid methyl esters of the acid-catalyzed methanolysis of the ceramides was analyzed and quantified by GC. Fatty acid composition was characterized by the predominance of acids with 21, 19 and 20 carbon atoms representing 38.5, 35.3 and 14.9 % of the total fatty acids, respectively. The location of the double bond in the common long chain base (LCB) was evidenced by the IE mass spectrum of the derivation product showing significant fragmentations which were strongly influenced by the sulfurated groups introduced.
F. Hichri, M.H. Oueslati, Sa. Hammami, H. Ben Jannet, P. Jean, M. Abreu, Z. Mighri
Reaumuria vermiculata, ceramides, fatty acids, long-chain base, RMN, GC/MS
Pages 83-89