1‐O‐alk‐1′‐enyl‐2‐acyl and 1‐O‐alkyl‐2‐acyl glycerophospholipids in white muscle of bonitoEuthynnus pelamis (Linnaeus)

The existence of ether‐linked phospholipids, including 1‐ O ‐alk‐1′‐enyl‐2‐acyl and 1‐ O ‐alkyl‐2‐acyl‐ sn ‐glycero‐3‐phosphocholines and ethanolamines in bonito Euthynnus pelamis (Linnaeus) white muscle, was investigated by gas chromatography and gas chromatography‐mass spectrometry. Chemical ionization ( iso ‐butane) mass spectrometry of trimethylsilyl ethers derived from the corresponding ether‐linked glycerophospholipids proved effective not only for determining molecular weights but also for structural identification based on the ions [M−R] + , [M−RO] + and [M+1] + . 1‐ O ‐Alk‐1′‐enyl‐2‐acyl‐ sn ‐glycero‐3‐phosphocholine and ethanolamine accounted for 3.0–6.0% and 3.6–7.6% of the total glycerophospholipids, respectively. 1‐ O ‐Alkyl‐2‐acyl‐ sn ‐glycero‐3‐phosphocholine and ethanolamine were also determined for one fish and accounted for 1.4% and 0.6% of the total glycerophospholipids, respectively. The predominant long chains in the sn ‐1 position of the glycerol moieties were 16∶0, 18∶0 and 18∶1 in the case of the alkenylacyl and alkylacyl components. Fatty acid distribution of individual glycerophospholipids was also determined.