Variation of lipid class and
fatty acid composition of Chaetoceros muelleri and Isochrysis
sp. grown in a semicontinuous system
F.
Pernet, R. Tremblay, E. Demers, M. Roussy-2003
Aquaculture, 221(1-4) : 393-406
Abstract:
The lipid class and the fatty acid composition of
microalgae are of primary importance in feeding filter-feeding animals
properly and variations of those parameters have never been investigated in
a cultivation system applied to hatcheries. The objective of this study was
to document the lipid class and fatty acid composition of the diatom Chaetoceros
muelleri (CHGRA) and the flagellate Isochrysis sp. (Clone TISO)
during the entire process of hatchery cultivation in relation to the period
of the year (summer vs. winter). At the beginning of the cultivation process
of CHGRA, in a small volume of culture, triacylglycerol (TAG), sterol,
saturated, monounsaturated, and polyunsaturated fatty acids (particularly
20:5n-3) were high, sharply dropping when volume was increased. An
inverse relationship has been observed for acetone mobile polar lipids
(AMPLs; pigment) and phospholipids (PLs), thus leading to no significant
effect of the volume of culture on the total lipid (TL) content of CHGRA.
The total lipid content of TISO increased with the volume of culture due to
AMPL and PL classes and saturated and polyunsaturated fatty acids. The
short- and long-term variability of lipid class composition has been
observed for both species. Such results highlight the high variability of
marine microalgae lipid content during the culture process and season as
well. Hatchery implication is discussed.
(GIROQ,
Université Laval, Cité Universitaire, Quebec, Canada G1K 7P4, e-mail of R.
Tremblay : Rejean.Tremblay@SODIM.org)