|Appears in Collections:||Aquaculture Journal Articles|
|Peer Review Status:||Refereed|
|Title:||Dynamics of fatty acid metabolism in a cell line from southern bluefin tuna (Thunnus maccoyii)|
Tocher, Douglas R
Schuller, Kathryn A
Fatty acid metabolism
|Citation:||Schofield A, Tocher DR & Schuller KA (2015) Dynamics of fatty acid metabolism in a cell line from southern bluefin tuna (Thunnus maccoyii), Aquaculture, 449, pp. 58-68.|
|Abstract:||Bluefin tunas are large predatorymarine fish of great commercial value but little is known of their specific nutritional requirements. The three species are farmed in sea cages in Australia, the Mediterranean, Mexico and Japan where they are fed small oily fish sourced from wild-catch fisheries. This may not be sustainable and, therefore, it is important to investigate the possible consequences of the replacement ofwild-catch fisheries products (fish oil and fish meal) with alternative oil and meal sources in feeds for these fish. To this endwe have studied fatty acid metabolism in a recently developed southern bluefin tuna (SBT, Thunnus maccoyii) cell line designated SBT-E1. The predominant fatty acids in the total lipid of the SBT-E1 cells were 16:0, 18:0 and 18:1n−9. There were also substantial amounts of 20:4n−6, 22:5n−3 and 22:6n−3 but only very limited amounts of 18:2n−6, 18:3n−3 or 20:5n−3. The fatty acid composition of the cells reflected that of the culture medium except that 20:4n−6, 22:5n−3 and 22:6n−3 were substantially more abundant in the cells than in the medium. Fatty acid esterification occurred predominantly into phosphatidylcholine (PC) and phosphatidylethanolamine (PE), the two most abundant classes of lipids. The SBT-E1 cells showed very limited Δ6 fatty acyl desaturase (Fads) activity towards either 18:3n−3 or 18:2n−6 but substantial elongation of very long chain fatty acids (Elovl) activity towards 20:5n−3. The latter activity is usually attributable to an Elovl5 enzyme. Surprisingly though, there were much higher levels of Δ6 Fads compared with Elovl5 gene expression in the SBT-E1 cells, suggesting that a different Elovl enzyme may catalyse this reaction in SBT. The cells also showed substantial β-oxidation of 18:3n−3 and 20:5n−3 but much less activity towards 18:0, 18:1n−9 or 18:2n−6. These results may explain the high 22:6n−3 to 20:5n−3 ratios found in the SBT tissue lipids, especially in the phospholipids. The results are discussed in terms of the presumed nutritional requirements of bluefin tunas given their high trophic level in marine food webs.|
|Rights:||The publisher does not allow this work to be made publicly available in this Repository. Please use the Request a Copy feature at the foot of the Repository record to request a copy directly from the author. You can only request a copy if you wish to use this work for your own research or private study.|
|Tocher_Aquaculture_2015.pdf||1.16 MB||Adobe PDF||Under Embargo until 31/12/2999 Request a copy|
Note: If any of the files in this item are currently embargoed, you can request a copy directly from the author by clicking the padlock icon above. However, this facility is dependant on the depositor still being contactable at their original email address.
This item is protected by original copyright
Items in the Repository are protected by copyright, with all rights reserved, unless otherwise indicated.
If you believe that any material held in STORRE infringes copyright, please contact email@example.com providing details and we will remove the Work from public display in STORRE and investigate your claim.