Marine lipids
performed on fatty acids of sponges from the order Haplosclerida. The
present comparative study is the first report on sponges collected along
the coast of Qatar, including seven Haplosclerida species.
Material and methods
The sponges were collected along the coasts of Qatar, either on the seashore in 1995 (Callyspongia sp. cf. siphonella, Callyspongia sp 1 , Callyspongia sp 2 , Gelliodes sp. cf. incrustans, or by scuba diving in 1996 (Gelliodes sp 1 , Gelliodes sp 2 , Niphates sp., Dysidea sp., and Leucetta sp.). All
these sponges belong to the order Haplosclerida, apart from Dysidea sp.
and the calcareous Leucetta sp. Total lipids (chloroform-methanol) were
separated into neutral lipids, glycolipids and phospholipids (methanolic
fraction) by column chromatography on silica gel. Fatty acid methyl
ester mixtures were obtained by reaction with MeOH/HCl and then
converted into N-acyl pyrrolidides (pyrrolidine/acetic acid). GC/MS
analyses of these derivatives were performed on an HP 5890 (GC)
linked to an HP 5989-A (MS); DB-1, 30 m x 0.25 mm; temperature:
200°C (4 min), 200°C to 300°C (3°C/min).
Results and discussion
More than 60 fatty acids were identified in each sponge phospholipid
(120 different fatty acids for all the sponges), including 22 typical A5,9
acids. An exceptional level of these A5,9 acids was found m Dysidea sp.
(68.7%). Leucetta sp. is the first calcareous sponge whose phospholipids
contain A5,9 fatty acids.
A new fatty acid, identifiecl as the l4-methyl-5,9-17:2 acid, was characterized in two sponges. The mass spectrum of the pyrrolidide displayed a molecular ion at m/z 333 (18:2), with an equivalent chainlength of 17.28 indicative of methyl branching. The major peak at
m/z 180 indicated a A5,9 unsaturation. The methyl branch was located at C14 since the ion at m/z 276 (C14) was much lower than the
ions at m/z 262 and m/z 290.
The rare Δ5,9,17-24:3 acid identified in Dysidea sp. was first detected
in a Dysidea sponge (Christie et al., 1992). Of interest was the occurrence of several unusual acids, namely Δ5,9-16:2, Δ5,9-18:2 and Δ5,920:2, and Δ6,11-18:2, Δ6,11-20:2 (Carballeira & Maldonado, 1989),
ancl Δ7,13-18:2, Δ7,13-20:2, as well as two brominated A5,9 acids
(Lam et al., 1989).
Acknowledgments
This work was supported by the French Foreign Ministry.
The following students were associated with this work: R. Tenta, T. Sapriki and
S. Markai.
76
performed on fatty acids of sponges from the order Haplosclerida. The
present comparative study is the first report on sponges collected along
the coast of Qatar, including seven Haplosclerida species.
Material and methods
The sponges were collected along the coasts of Qatar, either on the seashore in 1995 (Callyspongia sp. cf. siphonella, Callyspongia sp 1 , Callyspongia sp 2 , Gelliodes sp. cf. incrustans, or by scuba diving in 1996 (Gelliodes sp 1 , Gelliodes sp 2 , Niphates sp., Dysidea sp., and Leucetta sp.). All
these sponges belong to the order Haplosclerida, apart from Dysidea sp.
and the calcareous Leucetta sp. Total lipids (chloroform-methanol) were
separated into neutral lipids, glycolipids and phospholipids (methanolic
fraction) by column chromatography on silica gel. Fatty acid methyl
ester mixtures were obtained by reaction with MeOH/HCl and then
converted into N-acyl pyrrolidides (pyrrolidine/acetic acid). GC/MS
analyses of these derivatives were performed on an HP 5890 (GC)
linked to an HP 5989-A (MS); DB-1, 30 m x 0.25 mm; temperature:
200°C (4 min), 200°C to 300°C (3°C/min).
Results and discussion
More than 60 fatty acids were identified in each sponge phospholipid
(120 different fatty acids for all the sponges), including 22 typical A5,9
acids. An exceptional level of these A5,9 acids was found m Dysidea sp.
(68.7%). Leucetta sp. is the first calcareous sponge whose phospholipids
contain A5,9 fatty acids.
A new fatty acid, identifiecl as the l4-methyl-5,9-17:2 acid, was characterized in two sponges. The mass spectrum of the pyrrolidide displayed a molecular ion at m/z 333 (18:2), with an equivalent chainlength of 17.28 indicative of methyl branching. The major peak at
m/z 180 indicated a A5,9 unsaturation. The methyl branch was located at C14 since the ion at m/z 276 (C14) was much lower than the
ions at m/z 262 and m/z 290.
The rare Δ5,9,17-24:3 acid identified in Dysidea sp. was first detected
in a Dysidea sponge (Christie et al., 1992). Of interest was the occurrence of several unusual acids, namely Δ5,9-16:2, Δ5,9-18:2 and Δ5,920:2, and Δ6,11-18:2, Δ6,11-20:2 (Carballeira & Maldonado, 1989),
ancl Δ7,13-18:2, Δ7,13-20:2, as well as two brominated A5,9 acids
(Lam et al., 1989).
Acknowledgments
This work was supported by the French Foreign Ministry.
The following students were associated with this work: R. Tenta, T. Sapriki and
S. Markai.
76