Novel free ceramides as components of the soldier defense gland of the Formosan subterranean termite (Coptotermes formosanus)

• Published in: Journal of lipid research Vol. 48; no. 3; pp. 656 - 664
• Main Authors: Ohta, Masaya, Matsuura, Fumito, Henderson, Gregg, Laine, Roger A.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.03.2007; American Society for Biochemistry and Molecular Biology; Elsevier
• Subjects: Animals; Ceramides - analysis; Ceramides - chemistry; Ceramides - metabolism; Chromatography, Thin Layer; Fatty Acids, Nonesterified - analysis; Gas Chromatography-Mass Spectrometry; Isoptera - chemistry; Isoptera - metabolism; matrix-assisted laser desorption-ionization time-of-flight mass spectrometry; osmium tetroxide oxidation; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; sphingoid base; sphingoid base; matrix-assisted laser desorption-ionization time-of-flight mass spectrometry; osmium tetroxide oxidation
• ISSN: 0022-2275; 1539-7262
• DOI: 10.1194/jlr.M600387-JLR200

Of the lipid extracts of the defense secretion from the Formosan subterranean termite, Coptotermes formosanus Shiraki, on high-performance thin-layer chromatography analysis, no glycolipids or phospholipids were detected, but free fatty acids and three novel ceramides were found (termed TL-1, TL-2, and TL-3). Free fatty acids were confirmed to be lignoceric acid (C24:0) and hexacosanoic acid (C26:0), as described previously [Chen, J., G. Henderson, and R. A. Laine. 1999. Lignoceric acid and hexacosanoic acid: major components of soldier frontal gland secretions of the Formosan subterranean termite (Coptotermes formosanus). J. Chem. Ecol. 25: 817–824]. TL-1, TL-2, and TL-3 were characterized as ceramides differing in hydrophobicity based on results of matrix-assisted laser desorption-ionization time-of-flight mass spectrometry analysis, mild alkaline treatment, GC-MS analysis of fatty acid methylesters, and GC-MS analysis of sphingoid long-chain bases (LCBs) as trimethylsilyl derivatives. Fatty acids in TL-1 and TL-2 were C18:0, C20:0, and C22:0, and those in TL-3 were 2-hydroxy C18:0, C20:0, and C22:0. The most predominant LCB in TL-2 was a novel trihydroxy C14-sphingosine, 1,3,9-trihydroxy-2-amino-6-tetradecene. TL-3 contained C18-sphinganine and two kinds of novel sphingadienines, 1,3-dihydroxy-2-amino-7,10-hexadecadiene and 1,3-dihydroxy-2-amino-11,14-eicosadiene. Although examination of the biological activities of these novel ceramides was beyond the scope of these studies, because of the minuscule quantities available from termite secretions, it will be interesting in the future to synthesize these molecules for biological testing.