Triglyceride oxidation

Intravenous lipid emulsion particles are hydrolyzed in the bloodstream by the enzyme lipoprotein lipase to release free fatty acids and glycerol. Free fatty acids then are be taken up into adipose tissue for storage (triglycerides), oxidized to energy in various tissues (e.g., skeletal muscle), or recycled in the liver to make lipoproteins. 

Total polar materials Polymerized triglycerides Oxidized fatty acids Number of samples... 

Jeukendrup, A.E, Saris, W.H., Van Diesen, R., Brouns, E, and Wagenmakers, A.J. Effect of endogenous carbohydrate availability on oral medium-chain triglyceride oxidation during prolonged exercise. J. Appl. Physiol. 80, 949-954, 1996. 

Microemulsions are known to enhance the efficiency of antioxidants (Hanagan and Singh, 2006). Moberger and co-workers (1987) studied triglyceride oxidation in microemulsions consisting of soybean oil, sunflower oil monoglycerides and water. Soybean oil was stable against oxidation for an additional 50 days upon incorporation of 5% (w/w) ascorbic acid into the water phase compared to similar microemulsions without added ascorbic acid. 

Multiply unsaturated linolenic and linoleic acid residues make triglycerides more vulnerable to oxidative degradation than oleic acid which is relatively stable. It is therefore desirable to hydrogenate the most unsaturated residues selectively without production of large quantities of stearic (fully saturated) acid. The stepwise reduction of an unsaturated oil may be visualized as ... 

To produce highly purified phosphatidylcholine there are two industrial processes batch and continuous. In the batch process for producing phosphatidylcholine fractions with 70—96% PC (Pig. 4) (14,15) deoiled lecithin is blended at 30°C with 30 wt % ethanol, 90 vol %, eventually in the presence of a solubiHzer (for example, mono-, di-, or triglycerides). The ethanol-insoluble fraction is separated and dried. The ethanol-soluble fraction is mixed with aluminum oxide 1 1 and stirred for approximately one hour. After separation, the phosphatidylcholine fraction is concentrated, dried, and packed. 

Frouin (44), and more recently good evidence has been published (45) that nitric oxide reacts with palmitodiolein to form a pseudo-nitrosite across the double bonds of the triglyceride. 

Hepatic steatosis usually is a result of excessive administration of carbohydrates and/or lipids, but deficiencies of carnitine, choline, and essential fatty acids also may contribute. Hepatic steatosis can be minimized or reversed by avoiding overfeeding, especially from dextrose and lipids.35,38 Carnitine is an important amine that transports long-chain triglycerides into the mitochondria for oxidation, but carnitine deficiency in adults is extremely rare and is mostly a problem in premature infants and patients receiving chronic dialysis. Choline is an essential amine required for synthesis of cell membrane components such as phospholipids. Although a true choline deficiency is rare, preliminary studies of choline supplementation to adult patients PN caused reversal of steatosis. 

Oils. Among many investigated oils, soy oil, middle-chain triglycerides (MCT), safflower oil, and cottonseed oils are favoured for use as the oil phase due to their low incidence of toxic reactions. Purity is regarded as an important criterion for parenteral use. Undesirable contaminants such as hydrogenated oil, saturated fatty materials, pigments, or oxidative decomposition products should be minimized. 

Figure 5.15 GALDI mass spectra of (a) linseed oil (35 years airtight storage from THF solution) and (b) linseed oil as in (a) after 2 weeks of natural ageing (from THF solution). Signal groups of free fatty acids, their oxidation products, and monoglycerides (m/z <500) can be distinguished from diglycerides (m/z 500 800), and triglycerides (m/z 800 1000) (see Table 5.7)...

The product of cross-linking and oxidation processes in drying oils is described as a porous polymeric fraction with a wide range of molecular weight. The chemical structure that can be influenced by age, thickness and the presence of pigments, while nonbonded species are present in the interstices free mono- and dicarboxylic acids, mono-, di- and triglycerides, aldehydes, ketones, etc. 

Haila KM, Lievonen SM and Heinon IM. 1996. Effects of lutein, lycopene, annatto, and -y -tocopherol on oxidation of triglycerides. J Agric Food Chem 44 2096-2100. 

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