LIPID COMPOSITION OF COMMON BIVAlVE MOLLUSCAN SHELLFISH IN EGYPT.

LIPID COMPOSITION OF COMMON BIVAlVE MOLLUSCAN
SHELLFISH IN EGYPT.
By
N.A. SABER*
“‘National Institute of Oceanography & Fisheries, Anfoushy, Alexandria, Egypt.
Key words: Lipid, Shellfish.
ABSTRACT
Little is known about the composition of jlesh lipids of bivalve
molluscan shellfish Om-Elkholoul (Vedge shell, Donax trunculus) and
Gandoujly (Butter fish, Tapes spp.) which brought from Edco Lake
(Behera) and EI-Max region (Alexandria), respectively.
Lipid classes andfatty acid compositions ofjlesh lipids were studied.
Increased proportions of polar lipids in Om- Elkhouloul were mainly
due to increased percentage of phosphatidylcholine (PC),
phosphatidylethanolamine (PE), andplasmalogen.
In total polar lipids, saturatedfatty acids generally decreased and
mono-unsaturated fatty acids (derived from PE – plasmalogen) were
found to be higher in Om-Elkholoul than in the Gandoujly. However,
the proportions of polyunsaturated fatty acids in individual
phosphoglycerides were generally higher in Om-Elkholoul, due to
mainly increased docosahexaenoic acid (22:6 n-3), and were lowest in
Gandoujly. Relatively high percentage of oleic acid (18:1 n-9) was
found in all the phosphoglycerides, but primarily PC were higher in
Om-Elkholoul than in Gandoujly.
Fatty acids were distributted within individual phosphoglycerides
with a characteristic pattern that did not change with species, although
the relative amounts ofindividual fatty acids were altered.