Methyl linoleate

Methyl oleate gives methyl 9,10-dideuterostearate on treatment with deuterium. Similarly, methyl linoleate gives 9,10,12,13-tetradeuterostearate. The products have bp 214-215715 mm. 

Gonjugation of polyunsaturated fats Methyl linoleate with tris(triphenylphosphine) chlororhodium. J.Am. Oil Chem. Soc., 48, 21-24. 

NIKI E, SAITO T, KAWAKAMI A and KAMIYA Y (1984) Inhibition of oxidation of methyl linoleate by vitamin E and vitamin C, J Biol Chem, 259, 4177-82. 

PEDRiELLi p and SKIBSTED L H (2002) Antioxidant syneigy and regeneration effect of quercetin, (-)epicatechin, and (+)-catechin on a-tocopherol in homogeneous solutions of peroxidating methyl linoleate, JAgric Food Chem, 50, 7138-44. 

PEDRIELLI p, PEDULLi G F and SKIBSTED L H (2001a) Antioxidant mechanism of flavonoids. Solvent effect on rate constant for chain-braining reaction of quercetin and epicatechin in autoxidation of methyl linoleate, JAgric Food Chem, 49, 3034-40. 

ROGINSKY v A, BARSUKOVA T K, REMOROVA A A and BORS w (1996) Moderate antioxidative efficiencies of flavonoids during peroxidation of methyl linoleate in homogeneous and micellar solutions, J Am Oil Chem, Ti, 777-86. 

Figure 1.7 Typical zero-order and corresponding second-derivative electronic absorption spectra of ethanol-reconstituted lipid/chloroform extracts of autoxidized model polyunsaturated fatty-acid compounds and inflammatory synovial fluid obtained after (1) reduction with NaBH4 and (2) dehydration with alcoholic H2S04- (a) Methyl linoleate subsequent to autoxidation in air at ambient temperature for a period of 72 h (—), or exposure to a Fenton reaction system containing EDTA (5.75 x 10 mol/dm ), H2O2 (1.14 X 10 mol/dm ) and Fe(ll) (5.75 x IO mol/dm ) as an aqueous suspension (—) (b) as (a) but with methyl linolenate (c) untreated rheumatoid knee-joint synovial fluid.

Chan, H.W.S. and Levett, G. (1977). Autoxidation of methyl linoleate. Separation and analysis of isomeric mixtures of methyl linoleate hydroperoxides and methyl hydrox-ylinoleates. Lipids 12, 99. 

Yoshida, Y. and Niki, E. (1992). Oxidation of methyl linoleate in aqueous dispersions induced by copper and iron. Arch. Biochem. Biophys. 295, 107-114. 

Phenols are important antioxidants, with vitamin E being the most important endogenous phenolic membrane-bound antioxidant. Membrane levels of vitamin E are maintained through recycling of the vitamin E radical with ascorbate and thiol reductants. Vitamin E is a mixture of four lipid-soluble tocopherols, a-tocopherol being the most efiective radical quencher. The reaction of a-tocopherol with alkyl and alkylperoxyl radicals of methyl linoleate was recently reported. These are facile reactions that result in mixed dimer adducts (Yamauchi etal., 1993). 

Probucol, another di-r-butyl phenol, is an anti-atherosclerotic agent that can suppress the oxidation of low-density lipoprotein (LDL) in addition to lowering cholesterol levels. The antioxidant activity of probucol was measured, using EPR, with oxidation of methyl linoleate that was encapsulated in liposomal membranes or dissolved in hexane. Probucol suppressed ffee-radical-mediated oxidation. Its antioxidant activity was 17-fold less than that of tocopherol. This difference was less in liposomes than in hexane solution. Probucol suppressed the oxidation of LDL as efficiently as tocopherol. This work implies that physical factors as well as chemical reactivity are important in determining overall lipid peroxidation inhibition activity (Gotoh et al., 1992). 

Weinbeig, E.D. (1992). Iron depletion - a defense against intracellular infection and neoplasia. LifeSci. 50, 1289-1297. Yamauchi, R, Miyake, N., Kato, K., and Ueno, Y. (1993). Reaction of tocopherol with alkyl and alkylpcroxyl radicals of methyl linoleate. Lipids 8, 201-206. 

Silica has often been modified with silver for argentation chromatography because of the additional selectivity conferred by the interactions between silver and Jt-bonds of unsaturated hydrocarbons. In a recent example, methyl linoleate was separated from methyl linolenate on silver-modified silica in a dioxane-hexane mixture.23 Bonded phases using amino or cyano groups have proved to be of great utility. In a recent application on a 250 x 1-mm Deltabond (Keystone Scientific Belief onte, PA) Cyano cyanopropyl column, carbon dioxide was dissolved under pressure into the hexane mobile phase, serving to reduce the viscosity from 6.2 to 1 MPa and improve efficiency and peak symmetry.24 It was proposed that the carbon dioxide served to suppress the effect of residual surface silanols on retention. 

C12 to C20, primarily Ci6 to ( is), used as surface lubricants in the manufacture of food-contact articles. The method, which uses ethyl palmitate (Eastman Chemicals No. 1575 Red Label) as an internal standard, has been validated at 200 ppm total FAME [185]. Other FAME standards (methyl palmitate, methyl stearate, methyl oleate, methyl linoleate and methyl linolenate) are available (Applied Science Laboratories) [116], Worked out examples of additive determinations are given in the Food Additives Analytical Manual [116], which also describes a great many of indirect food additives, such as BHA, BHT, TBHQ, l-chloro-2-propanol, DLTDP, fatty acid methyl esters, w-heptyl-p-hydroxybenzoate, propyl-gallate, sodium benzoate, sodium stearoyl-2-lactylate, sorbitol and phenolic antioxidants. EPA methods 606 and 8060 describe the CGC separation of phthalate esters (direct injection) (cf. Figure 4.2). 

A base-catalyzed tert-C4H9OK) reaction of jV /V -oxalyldiimidazole, prepared in situ from oxalyldichloride and imidazole, to give methyl linoleate (93%) is described in reference [111]. 

Yamauchi, R. and K. Kato (1998). Products formed by peroxyl radical-mediated oxidation of canthaxanthin in benzene and in methyl linoleate. J. Agric. Food Chem. 46(12) 5066-5071. 

Yamauchi, R. et al. (1998). Oxidation products of beta-carotene during the peroxidation of methyl linoleate in the bulk phase. Biosci. Biotechnol. Biochem. 62(7) 1301-1306. 

Larva Trigger workers to cap larval cells Methyl linoleate 82, linolenate 84, oleate 56, palmitate 78 [147]... 

Larva Increases deposition of royal jelly into queen cells Methyl linoleate 82 [149]... 

Yellow and red onions (Allium cepa) were reported to be poor antioxidants toward oxidation of methyl linoleate (Kahkonen and others 1999) in contrast to their high antioxidant activity toward oxidation of LDL (Vinson and others 1998). Garlic (Allium sativum L) was reported to have four times more antioxidant activity than onions when using the ORAC assay (Cao and others 1996). 

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