Linolenic acid sources

Some fatty acids are not synthesized by mammals and yet are necessary for normal growth and life. These essential fatty aeids include llnoleic and y-linolenic acids. These must be obtained by mammals in their diet (specifically from plant sources). Arachidonic acid, which is not found in plants, can only be synthesized by mammals from linoleic acid. At least one function of the essential fatty acids is to serve as a precursor for the synthesis of eicosanoids, such as... 

Carrots (Daucus carota) are excellent sources of (3-carotene and vitamin A, although they have been reported to exert low antioxidant activity compared to some other vegetables (Al-Saikhan and others 1995 Cao and others 1996 Ramarathnam and others 1997 Vinson and others 1998 Beom and others 1998). However, boiling carrots for 30 min significantly improved their antioxidant activity toward coupled oxidation of (3-carotene and linolenic acid (Gazzani and others 1998). 

There are several sources of y-linolenic acid including evening primrose, borage and blackcurrant oils. Indeed, the evening primrose is grown commercially for the production of y-linolenic acid. It is available in most health food shops and pharmacies. 

The sources of these fatty acids in the cells are those that are present at position 2 of the membrane phospholipids. The proportion of these two in the phospholipid depends to a large extent on the type of fatty acids in the triacylg-lycerol in the diet, that is, the amount of the omega-6 (lin-oleic acid) and that of the omega-3 (a-linolenic acid). 

One of the interesting effects of ozone is the 56% increase in the linolenic acid content of ASG from ozonated bean leaves ( ), This led us to explore the source of the additional linolenic acid, Ongun and Mudd ( ) had reported that SG and ASG normally formed at the expense of free sterols in non-ozonated plants. What happens in ozonated plants ... 

Dietary intake is of great importance. Linoleic acid (C18 2o)6) and a-linolenic acid (C18 3o)3) are the parent essential fatty acids for humans. Both fatty acids derive from vegetable oils. Higher fatty acids are then produced by chain elongation and desaturation. In addition, some of the prime essential fatty acids, AA (C20 4o)6), EPA (C20 5w3) and DHA (C22 6w3), can be obtained directly from the diet. Meat and eggs are rich in AA, whereas fish is a rich source of EPA and DHA [14]. 

Raw material Yield C02 extraction [%] Source C]8 3 in the extract (/ linolenic acid) [%]... 

More importantly, lipid peroxidation can be controlled or minimized by design of formulation. While saturated lipids (e.g., MCTs) will themselves not be susceptible to peroxidation, they may contain sufLcient unsaturated impuritiesto be problematic. Similarly, monounsaturated lipids (e.g., oleic acid glycerides) are much less susceptible to peroxidation. The relative rates of peroxidation of oleic, linoleic, and linolenic acids are 6 64 100, respectively (Swern, 1995). Monounsaturated lipids may, however, may contain polyunsaturated impurities, which will catalyze the oxidation ofthe monounsaturated components (Swern, 1995). Surfactants, particularly those based on PEG, may contain peroxides that can promote lipid peroxidation thus, particular attention should be paid to the purity and source of all formulation components. 

Batterham, E.S., Andersen, L.M., Baigent, D.R. and Green, A.G. (1991) Evaluation of meals from Linola(R) low-linolenic acid linseed and conventional linseed as protein sources for growing pigs. Animal Feed Science and Technology 35,181-190. 

If that does occur, then the present system of classification of oils may be impossible to police, and a modified system may become necessary. Perhaps the sale and perceived value of oils will necessarily become dependent on the performance, not the source of the oil. With bulk oils such as palm, peanut, sunflower, safflower, sesame, soya, rapeseed, com, fish, and animal fats and oils, the fatty acid composition will obviously be important for health reasons. If the oil is to be used for frying then the frying properties will be important. In the case of palm products the physical properties and minor components such as carotenoids will be defined. Similarly animal fats will be judged mainly on physical behaviour and effect on the product in which they are used. In all cases the oxidative and stability of the oil will have to be defined. Sesame is a very stable oil, and thus its stability, together with its low level of linolenic acid, would be its major attribute, except for toasted sesame, which would probably be classed as a specialist oil. Already most baking fats sold to the public are blends developed to give the best performance, with no mention on the pack as to the source. If a bulk oil of this type had the desired chemical composition, stability and cooking behaviour, then perhaps the source would not be a matter of concern. 

Sensidoni, A., Bortolussi, G., Orlando, C. and Fantozzi, P. (1996) Borage oil (Bortago officinalis L.) an important source of gamma linolenic acid. II. Tocopherols and chlorophyll content and sensorial analysis of borage oils extracted by different techniques and blended with extra virgin olive oil. lnd. Aliment., 35, 664-669. 

Oleic acid was increased to 48% of total milk fatty acids by feeding oleamide as a rumen-protected source of oleic acid (Jenkins, 1998). The response was nearly linear up to 5% of supplement in the diet dry matter. Proportions of all de uovo-synthesized milk fatty acids, except butyric, were reduced (Jenkins, 1999). LaCount et al. (1994) abomasally infused fatty acids from canola or high oleic acid sunflower oil into lactating cows. The transfer of oleic acid to milk fat was linear (slope = 0.541 0 350 g infused/ day) the proportion of oleic acid in milk fat increased and proportions of all de novo-synthesized fatty acids, except C4 and C6 decreased. The proportion of Ci8 o also was unchanged. Linoleic acid from canola also was transferred linearly (slope = 0.527 0-90 g infused/day). These transfers from the intestine are nearly identical to that reported by Banks et al. (1976). Hagemeister et al. (1991) reported 42 to 57% transfer of abomasally-infused linolenic acid to milk fat. 

There are few reports on the inhibitory effect of conjugated polyenes on the growth of cancer cell lines. Begin et al. (1988) reported the toxic effect of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) on several kinds of tumor cells other polyunsaturated fatty acids, i.e., arachidonic acid (22 4n-6), a-linolenic acid (18 3n-3), and y-linolenic acid (18 3n-6) have cytotoxic action on several tumor cell lines at concentrations above 50 pM. Further, Tsuzuki et al. (2004) demonstrated that the anticarcinogenic effect of CLN are directly associated with lipid peroxidation. They transplanted human colon cancer cells (DLD-1) into nude mice, and CLA (9c, lit and lOt, 12c-18 2) and CLN (9c, lit, 13t-18 3) were administered to animals. Tumor growth was suppressed by the supplementation of CLA and CLN, and the extent of suppression was CLN >9c, llt-CLA.>10t, 12c-CLA, in that order. Furthermore, DNA fragmentation was enhanced and lipid peroxidation increased in tumor cells of the CLN-fed mouse. Thus this study indicates the possibility of seaweeds as potential sources of anticancer substances. 

Linolenic acid is always obtained from natural sources, chiefly from the oils of various seeds, such as hemp seed,1 walnut,2 poppy seed,2 cotton seed,2 and, best of all, linseed.3, 4 The crude acid has been purified via the solid hexabromide, either directly, 5> 6... 

You may hear about getting omega-3s from plant sources, especially flaxseed and flaxseed oil but also from soybeans, canola and walnut oils, and various kinds of nuts. All of those foods contain a far less potent form of the beneficial fatty acids called alpha-linolenic acid (ALA). You may even see ALA supplements on sale in health food stores and pharmacies, but only a fraction, a small fraction, of ALA is converted by the body into EPA and DHA. Stick with the fish oils or the concentrated ethyl ester supplements. 

Linoleic and linolenic acids are essential fatty acids, meaning they cannot be synthesized in the body and must therefore be obtained in the diet. A common source of these essential fatty acids is whole milk. Babies fed a diet of nonfat milk in their early months do not thrive because they do not obtain enough of these essential fatty acids. 

Table 4.2 lists some common examples of fatty acids, their sources, common names, and systematic names [1]. Many additional terms are used to distinguish unsaturated fatty acids by the location of the first double bond relative to the omega (co) or —CHg carbon. Thus oleic acid is both A and a C18 1 co-9 acid. Linoleic acid is a and C18 2 (0-6 acid. Linolenic acid is both and a C18 3 co-3 acid. 

Linoleic acid and linolenic acid are essential fatty acids that cannot be made by animals and must be obtained by dietary intake from plant sources. When metabolized in animals, these two acids each give rise to a family of Cig, C20, and C22 n-6 and n-3 polyunsaturated fatty acids thus ... 

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