Conjugated linoleic acid is synthesized endogenously in lactating dairy cows by Delta(9)-desaturase.
J. M. Griinari,Benjamin A. Corl,Shannon H. Lacy,P. Y. Chouinard,K. V. V. Nurmela,Dale E. Bauman +5 more
TLDR
Results demonstrate that endogenous synthesis of CLA from trans-11 18:1 represented the primary source of CLA in milk fat of lactating cows.Abstract:
Conjugated linoleic acid (CLA) is a naturally occurring anticarcinogen found in milk fat and body fat of ruminants. Although CLA is an intermediate in ruminal biohydrogenation of linoleic acid, we hypothesized that its primary source was from endogenous synthesis. This would involve Delta(9)-desaturase and synthesis from trans-11 18:1, another intermediate in ruminal biohydrogenation. Our first experiment supplied lactating cows (n = 3) with trans-11 18:1 by abomasal infusion and examined the potential for endogenous synthesis by measuring changes in milk fat CLA. By d 3, infusion of trans-11 18:1 resulted in a 31% increase in concentration of cis-9, trans-11 CLA in milk fat, demonstrating that an active pathway for endogenous synthesis of CLA exists. Our second experiment examined the quantitative importance of endogenous synthesis of CLA in lactating cows (n = 3) by abomasally infusing a putative stimulator (retinol palmitate) or an inhibitor (sterculic oil) of Delta(9)-desaturase. Infusion of retinol palmitate had no influence on milk fatty acid desaturation, and yield of CLA in milk fat was not altered. However, sterculic oil infusion decreased the concentration of CLA in milk fat by 45%. Consistent with Delta(9)-desaturase inhibition, the sterculic oil treatment also altered the milk fat concentration of other Delta(9)-desaturase products as indicated by the two- to threefold increase in the ratios of 14:0 to 14:1(,) 16:0 to 16:1 and 18:0 to cis-18:1. Using changes in the ratio of 14:0 to 14:1 as an indication of the extent of Delta(9)-desaturase inhibition with the sterculic oil treatment, an estimated 64% of the CLA in milk fat was of endogenous origin. Overall, results demonstrate that endogenous synthesis of CLA from trans-11 18:1 represented the primary source of CLA in milk fat of lactating cows.read more
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Fatty acid profile and health lipid indices in the raw milk of ewes grazing part-time and hemp seed supplementation of lactating ewes
TL;DR: In this article, the effects of the feeding system (indoor or part-time grazing) of ewes and dietary supplementation with hemp seed (non-drug varieties of Cannabis sativa L.) on milk production and the composition of milk fatty acids (FAs).
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Can the trans-18:1 and conjugated linoleic acid profiles in retail ground beef be healthier than steak?
TL;DR: A seasonal survey of western Canadian retail ground beef was undertaken with emphasis on trans fatty acid (trans-FA) and conjugated linoleic acid (CLA) isomer profiles as mentioned in this paper.
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Conjugated linoleic acid and vaccenic acid contents in cheeses: An overview from the literature
TL;DR: The conjugated linoleic acids (CLA) and vaccenic (C18:1 trans-11; C18: 1 t-11) acid contents of cheeses have been reported in many publications as mentioned in this paper.
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Influence of conjugated linoleic acids on functional properties of vascular cells.
Robert Ringseis,Klaus Eder +1 more
TL;DR: Results from in vitro studies dealing with the effects of CLA isomers and CLA mixtures on functional properties of cells of the vascular wall, such as endothelial cells, smooth muscle cells and monocyte-derived macrophages, which are amongst the major cells contributing to atherosclerotic lesion development are summarized.
Journal ArticleDOI
Progress in Nutritional and Health Profile of Milk and Dairy Products: A Novel Drug Target
TL;DR: There are still uncertainties about the health benefits of various milk FAs and other compounds; deep and extensive long-term clinical studies with humans are needed.
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