Content area
Full text
Abstract The phospholipid fatty acid composition of the North-East Atlantic sponge Polymastia penicillus (South Brittany, France) was investigated. Sixty fatty acids (FA) were identified as methyl esters (FAME) and N-acyl pyrrolidides (NAP) by gas chromatography-mass spectrometry (GC/MS), including eight Δ5,9 unsaturated FA and three long-chain 2-hydroxylated FA. The major phospholipid FA were palmitic (14.3% of the total FA mixture), vaccenic (12.7%), 15(Z)-docosenoic (13.4%) and 5(Z),9(Z)-hexacosadienoic (13.3%) acids. In addition to the iso- and anteiso-branched saturated FA, several unusual short-chain branched saturated FA were identified. In addition to the known Δ5,9 FA, and interestingly regarding their identification by GC-MS as N-acyl pyrrolidides, was the co-occurrence of unusual FA possessing a Δ3, Δ4 and Δ5 double bond such as iso-4-pentadecenoic, iso-5-heptadecenoic, anteiso-5-heptadecenoic and two new compounds, not hitherto found in nature, namely 17-methyl-13-octadecenoic (0.8%) and 3,16-docosadienoic (1.1%) acids.
Keywords 3,16-Docosadienoic acid * Fatty acids * Phospholipids * Polymastia * Sponge * 17-Methyl-13-octadecenoic * N-Acyl pyrrolidides * Non-methylene-interrupted fatty acids
Abbreviations
amu Atomic mass unit
FA Fatty acid(s)
FAME Fatty acid methyl ester(s)
GC/MS Gas chromatography-mass spectrometry
MS Mass spectrum (spectra)
NAP N-Acyl pyrrolidide(s)
NMI Non-methylene-interrupted
TLC Thin layer chromatography
Introduction
Marine sponges are primitive invertebrates with a remarkable ability to adapt to environmental changes. Thus, they have given rise to intensive investigations into the basic lipid components of their cell membranes since the pioneer studies [1, 2]. The phospholipid fatty acid composition is important for the functions of the cell membranes [3, 4]. In addition, sponge phospholipid classes have also been examined [3-5]. Moreover, sponges have proved to be a rich source of many unusual sterols and fatty acids (FA). Common polyunsaturated FA from the n-6 and n-3 series, such as eicosapentanoic acid EPA and docosahexaenoic acid DHA, are quite rare in sponge phospholipids, that instead usually contain very long-chain (C^sub 22^-C^sub 34^) non-methylene-interrupted (NMI) FA including the particular unsaturation pattern Δ5,9 [3, 4, 6-11].
Sponges from the genus Polymastia are known to contain secondary metabolites with biological activity but there have been, in comparison, few investigations of their primary metabolites such as FA and sterols to date. Thus, organic extracts of Polymastia janeirensis demonstrated in vitro cytotoxicity against HT29 colorectal tumor cell lines [12]. Polymastia croceus has been farmed in order to produce quantities of...