Function and metabolism
A supply of Skeletonema costatum
for six week changes chemical and fatty
acid composition of adult oyster
Frédérique Piveteau
(1) , Gilles Gandemer
(2) , Jean-Pierre Baud
(3) ,
Michel Demaimay
(1)
(1) Enitiaa, laboratoire de biochimie industrielle et alimentaire,
BP 82225, 44072 Nantes Cedex 3, France - piveteau@enitiaa-nantes.fr
(2) Inra, laboratoire d’étude des interactions des molécules alimentaires, équipe lipides,
BP 71627, 44326 Nantes Cedex 3, France
(3) Ifremer Bouin, laboratoire conchylicole des Pays de la Loire, polder des champs,
85230 Bouin, France
Abstract
To improve oyster condition index, Skeletonema costatum have been
supplied to adult oysters (Crassostrea gigas). However, the consequences
of this practice on compositional traits of oysters were not investigated.
The study deals with the chemical changes in adult oysters fed with
Skeletonema costatum during six weeks in ponds with emphasis on lipids.
The results showed that:
• Supplementation of Skeletonema costatum for six weeks improved condition index (x 2) of oysters by increasing their glycogen content (x 5).
Lipid content remained steady in controls and slightly increased in
supplemented oysters (8.4% versus 10.4% dry matter);
• Large changes in fatty acid composition of total lipids were observed.
Some fatty acids of Skeletonerna costatum, such as 16:1 (n-7) and 20:5 (n-3),
were directly accumulated into oyster’s lipids;
• The 16:1 (n-7) was elongated into 18:1 (n-7) showing that oysters are
able to elongate 16 carbon monounsaturated fatty acids into the corresponding 18 carbon fatty acids;
• Fatty acids typical of Skeletonema costatum (16:4 (n-1), 16:2 (n-4),
16:3 (n-4) were poorly accumulated into total lipids of oysters suggesting
that oysters discriminate these fatty acids.
Résumé
Pour améliorer leur indice de condition, des huîtres adultes (Crassostrea gigas) sont affinées avec la microalgue Skeletonema costatum pendant
six semaines. Cette étude a pour objectif d’évaluer les modifications des
caractéristiques biochimiques des huîtres affinées en claires pendant
six semaines avec Skeletonema costatum et notamment les modifications
des caractéristiques lipidiques.
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A supply of Skeletonema costatum
for six week changes chemical and fatty
acid composition of adult oyster
Frédérique Piveteau
(1) , Gilles Gandemer
(2) , Jean-Pierre Baud
(3) ,
Michel Demaimay
(1)
(1) Enitiaa, laboratoire de biochimie industrielle et alimentaire,
BP 82225, 44072 Nantes Cedex 3, France - piveteau@enitiaa-nantes.fr
(2) Inra, laboratoire d’étude des interactions des molécules alimentaires, équipe lipides,
BP 71627, 44326 Nantes Cedex 3, France
(3) Ifremer Bouin, laboratoire conchylicole des Pays de la Loire, polder des champs,
85230 Bouin, France
Abstract
To improve oyster condition index, Skeletonema costatum have been
supplied to adult oysters (Crassostrea gigas). However, the consequences
of this practice on compositional traits of oysters were not investigated.
The study deals with the chemical changes in adult oysters fed with
Skeletonema costatum during six weeks in ponds with emphasis on lipids.
The results showed that:
• Supplementation of Skeletonema costatum for six weeks improved condition index (x 2) of oysters by increasing their glycogen content (x 5).
Lipid content remained steady in controls and slightly increased in
supplemented oysters (8.4% versus 10.4% dry matter);
• Large changes in fatty acid composition of total lipids were observed.
Some fatty acids of Skeletonerna costatum, such as 16:1 (n-7) and 20:5 (n-3),
were directly accumulated into oyster’s lipids;
• The 16:1 (n-7) was elongated into 18:1 (n-7) showing that oysters are
able to elongate 16 carbon monounsaturated fatty acids into the corresponding 18 carbon fatty acids;
• Fatty acids typical of Skeletonema costatum (16:4 (n-1), 16:2 (n-4),
16:3 (n-4) were poorly accumulated into total lipids of oysters suggesting
that oysters discriminate these fatty acids.
Résumé
Pour améliorer leur indice de condition, des huîtres adultes (Crassostrea gigas) sont affinées avec la microalgue Skeletonema costatum pendant
six semaines. Cette étude a pour objectif d’évaluer les modifications des
caractéristiques biochimiques des huîtres affinées en claires pendant
six semaines avec Skeletonema costatum et notamment les modifications
des caractéristiques lipidiques.
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