Identification of Fatty Acid Methyl Esters, Long Chain Aldehydes and Free Fatty Acids in a Sponge Chalinula saudensis along the coast of Jeddah, Saudi Arabia

Abstract

Fatty acid methyl esters in a sponge Chalinula saudensis were isolated and identified. It is a rare sponge isolated and identified along the coast of Jeddah in 2000. The chemical constituents were extracted by solvent extraction. Chloroform layer was further subjected to separation of the components by thin layer chromatography. The fatty acid esters were identified by GC-MS. It was observed that sixteen fatty acid methyl esters were detectable , ranging from C₁₅ to C₂₃ , four out of sixteen esters were saturated the rest contained from one to six double bonds. The most important among these were eicosapentanoic acid (EPA) and docosahexanoic acid (DHA). Both of these are known to be effective as antilipemic agent (reducing the cholesterol level). In addition to these compounds three free long chain fatty acids: decedanoic acid, n-hexadecanoic acid and octadecanoic acid were prominent. Aldehydes: tridecanal, octadecanal and octadecenal were also detected. The dominance of unsaturated fatty esters indicates the dependence of the organisms on heterotrophism.