Conjugated linolenic acid

Other factors are also claimed to affect the fatty acids in milk. Cattle low in copper are reported to give milk higher in conjugated linolenic acid (Sol-Morales... 

Offer, N.W., Marsden, M., Dixon, J., Speake, B.K. and Thacker, F.E. (1999) Effect of dietary fat supplements on levels of n-3 polyunsaturated fatty acids, trans acids and conjugated linolenic acid in bovine milk. Animal Sci., 69, 613—625. 

A reaction medium that contains 40% soaps by weight can usually be dissolved in ethanol. We have found that 100 mg of reaction mixture will totally dissolve in 10 mL of 95% ethanol when glycerol, water, or ethylene glycol are the reaction solvent and alkali hydroxides are used as the catalyst. It is then possible to dilute the reaction mixture solution 1000-fold to determine the UV absorbance at 231.5 nm. When there is no other interfering UV absorbance, this method is an excellent indication of the total conjugated double bonds. This method is also sensitive to the presence of conjugated linolenic acids derived from linolenic acid, which is indicated by a UV absorbance at 268 nm. None of the samples observed show three conjugated double bonds. 

Kohno, H., R. Suzuki, Y. Yasui, et al. 2004. Pomegranate seed oil rich in conjugated linolenic acid suppresses chemically induced colon carcinogenesis in rats. Cancer Sci. 95(6) 481-486. 

Bioconversion of Conjugated Linolenic Acid to Conjugated Linoleic Acid... 

Changes in Fatty Acid Composition of Total Lipids from Caco-2 Cells After Incubation With or Without c9,fl1,f13-Conjugated Linolenic Acid (CLN) ... 

Kohno, H., Suzuki, R., Noguchi, R., Hosokawa, M., Miyashita, K., and Tanaka, T. (2002) Dietary Conjugated Linolenic Acid Inhibits Azoxymethane-Induced Colonic Aberrant Crypt Foci in Rats, Jpn. J. Cancer Res. 93,133-142. 

Lerch, S., Shingfield, K. J., Ferlay, A., Vanhatalo, A., Chilliard, Y. (2012). Rapeseed or linseed in grass-based diets effects on conjugated linoleic and conjugated linolenic acid isomers in milk fat from Holstein cows over 2 consecutive lactations. Journal of Dairy Science, 95,1269-11% . 

Fig. 6.11. Acetonitrile CIMS spectra of homoallylic, partially conjugated (pCLnA), and fully conjugated linolenic acid (fCLnA) methyl esters. The abundance of the m/z 346 [M-t54]+ ion relative to the m/z 314 [M-t54-32]+ ion consistently differs in each mass spectrum and suggests a means to distinguish the various geometries.

As mentioned earlier in this chapter for CLA methyl esters, acetonitrile CIMS has been shown to distinguish between conjugated and homoallylic FAME by the ratio of [M+54] /[M+54-32] ion abundances. When applied to a variety of conjugated linolenic acid (CLnA) methyl ester standards, a similar differentiation is seen. 

Suzuki, R., et al.. Occurrence of Conjugated Linolenic Acid in Flesh and Seed of Bitter... 

Fig. 19.5. Desaturation and elongation pathway of CLA A6 desatureise is a rate-limiting step. CLNA, conjugated linolenic acid CDGLNA, conjugated di-homo-y-linolenic acid CAA, conjugated arachidonic acid.

Yurawecz et al. (1993) found traces (up to 0.2%) of conjugated linolenic acid (CLN) in vegetable oils in their study of 27 oils for CLN content by ultraviolet (UV) measurement. The isomers were identified as a-eleostearic acid (9cis(c),lltrans (t),13t-18 3), P-eleostearic acid (9t,llt,13t-18 3) and 8t,10t,12t-18 3. HPLC analysis of purified soyabean oil methyl esters indicates the presence of small amounts of CLA... 

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