Egg phospholipids

Osterherg, T. Svensson, M. Lundahl, P, Chromatographic retention of drug molecules on immohilized liposomes prepared from egg phospholipids and from chemically pure phospholipids, Eur. J. Pharm. Sci. 12, 427 139 (2001). 

Naturally occurring phospholipids can be isolated from a variety of sources. One of the most common phospholipid raw materials is egg yolk. However, since the composition of egg phospholipid is from a biological source and can vary considerably depending on age of the eggs, the diet of the chickens, and the method of processing, newer enzymatic and synthetic chemical methods now are being employed to manufacture the required phospholipid derivatives in higher purity and yield. 

When oxidized, 1 g of fat yields 9 kcal. Because of the caloric contribution from egg phospholipid and glycerol, caloric content of IVFE is 1.1 kcal/mL for the 10%, 2 kcal/mL for the 20%, and 3 kcal/mL for the 30% emulsions. 

Egg phospholipids. At one time, eggs, which possess a relatively high phospholipid content, served as a commercial source until soybean technology made it uneconomical to produce. The phospholipids in eggs are mainly in the yolk, where at least a portion of them are combined with protein and carbohydrates. 

The FDA has issued a guidance suggesting that animal-derived materials such as egg yolk lecithin, and egg phospholipid) used in drug products, originating from Belgium, France, and the Netherlands between January and June 1999 should be investigated for the presence of dioxin and polychlorinated biphenyls. The contamination in the animal-derived product was probably due to contaminated animal feed. 

Animal phospholipids, especially egg phospholipids or egg yolk, are the key precursors for a patent application, which claims the reaction with a sulphur-containing compound like cysteine to produce meaty flavours ]102], Phospholipids and monoglycerides can play a fundamental role in the physical structure of a process flavour. Vauthey and co-workers ]103] use these emulsifiers in water to generate nanostmctured mesophases or microemulsions at the reaction temperature. Better aroma yields and different aroma compounds were obtained in these nanostmctured reaction media compared to aqueous solutions. 

Phospholipid is added in a 1 4 molar ratio to taurocholate, which is within the physiological relevant range. Egg phospholipid is recommended, as its fatty acid composition is close to the one in human bile phospholipids. Studies by Naylor et al. (Naylor et al., 1993 Naylor et al., 1995) demonstrated the importance of adding phospholipids, especially when dealing with hydrophobic drug... 

As for FaSSlF, taurocholate is used as bile salt and egg phospholipids are recommended as phospholipids. The ratio between bile salt and phospholipids is kept at 4 1, even though ingested food often contains phospholipids that will decrease this ratio. 

Diazpam (Baxter) Dizac (R) Anxiety, epilepsy (I.V. administration only) drug (2), fractionated soybean oil (150), diacetylated monoglycerides (50), egg phospholipids (12), glycerin (22), sodium hydroxide, pH = 8 125-126°C 2.82 (experimental)... 

Eor parenteral nutrition drug-free emulsions are used. A typical composition of a nutritional fat emulsion for i.v. administration is 200 g soybean oil or safflower oil, 12 g egg phospholipids and 25 g glycerine per liter of emulsion with the pH adjusted to within the range 5.5-8. It is most important that the fat droplet particle size that does not exceed 0.5 pm. For experimental purposes, such fat emulsions (e.g. Abbolipid , IntraUpid , Lipofundin ) are well suited and used as early dosing vehicles for lipophilic drug candidates. 

FAT EMULSION For parenteral nutrition a fat emulsion for intravenous administration is used. Preparations contain a fractionated soya-oil emulsified with some fractionated egg phospholipids. About 60% of the fatty acids are essential fatty acids the particle size and biological properties are similar to those in natural chylomicrones. 

Moschidis, M.C., Demopoulos, C.A., and Kritikou, L.B. 1984. Isolation of hens egg phospholipids by thin layer chromatography, their identification and silicic acid column chromatographic separation, J. of Chromatogr., 292, 473. 

A. Parenteral. Propofol (Diprivan) 1% (10 mg/mL) emulsion in 10% soybean oil with 2.25% glycerol and 1.25% purified egg phospholipid in 20-, 50-, or 100-mL vials and a 50-mL prefilled syringe. Contains disodium EDTA or sodium metabisulfite in the US formulation as preservatives. A 2% (20 mg/mL) emulsion has been formulated to provide the same amount of drug with less lipid concentration, but is not yet approved in the United States. Note Propofol is provided as a ready-to-use preparation, but if dilution is necessary, only use D5W and don t dilute to conoentrations less than 2 mg/mL. 

Consistent with this hypothesis is the work of Carlson et al. (9) who reported a reduced incidence of NEC in infants fed a preterm formula supplemented with egg phospholipids. The supplemented formula contained 0.4% of total fatty acids as ARA and 0.13% of total fatty adds as docosa-hexaenoic acid (DHA). The incidence of NEC in infants receiving the supplemented formula was 2.9%, compared with 17.6% in the control group. 

Various sources of LC-PUFA for infant formula supplementation are available. They include fish oil, egg phospholipids, and single-cell oil. DHA is available primarily from the marine food chain, i.e., marine fish, shellfish, and algae. Although fish oil is the most readily available source of DHA, it has an undesirably high eicosapentaenoic acid (EPA, 20 5n-3) level, which may interfere with AA status and growth (6). Consequently, the addition of both DHA and AA to infant formulas has been recommended. Egg phospholipid is another dietary source for DHA and AA. Direct addition of egg yolk to formula may produce phospholipid levels far greater than levels found in breast milk. However, a tracer experiment has demonstrated that DHA and AA are better absorbed in phosphoUpid form than in the triacylglyc-eride form found in breast milk and other LC-PUFA sources (7). 

A study has been made to show the validity of the quantitative determination of egg phospholipids in a pharmaceutical liposome preparation by means of NMR spectroscopy (Table 4.6 Diehl et al., 1996b). Selectivity and recovery depend on the matrix and have to be tested in each individual... 

Farmer, Mottram and Whitfield studied volatile compounds produced in Maillard reactions involving cysteine/ribose with and without an egg phospholipid upon autoclaving at 140 C for 1 hour. The pH was maintained at 5.7 with phosphate buffer. They found that Fur-SH was a major volatile component, and its generation was independent of the presence of phospholipid (10). 

With the development of stable, energy dense, isotonic lipid emulsions for intravenous use (Table IV), the use of concentrated glucose solutions which have to be infused through large calibre central veins has decreased. Administration of nutrients by peripheral vein eliminates the complications associated with central catheter placement and use (Jako-bowski et al., 1979). Intravenous fat emulsions are manufactured from either soyabean or safflower oil, stabilized with 1.2% egg phospholipid, and made isotonic with 2.5% glycerol. Formulations are rich in essential fatty acids, yield 1.1 kcal/ml, and have a metabolic fate which is similar to that of naturally occurring chylomicrons. Liposyn, however, has only trace amounts of linolenic acid compared to the two other emulsions. In addition, carnitine is absent from all of the lipid emulsions. 

Propofol, 2,6-diisopropylphenol, is administered intravenously and nsed in general anesthesia as a short-acting indnction and maintenance agent The drug is formulated as an oil-water emulsion containing 1 % propofol, soybean oil 10 %, glycerol, and egg phospholipid as emulgent. 

Nonphosphorus molecules always accompany plant or egg phospholipids with amphiphilic characteristics, which are termed glycolipids. The main glycolipids are diglyceride ethers of mono- or disaccharides (Danisco Co., Copenhagen, private communication) (Fig. 30). 

Phosphatidylcholine from other egg phospholipids Phosphatidylcholine from other egg phospholipids Isolation of total phospholipids (phosphatidylcholine, phos-phatidylethanolamine, and phosphatidylinositol) from soybean extract Isolation of phosphatides from total lipids in eggs, meat, and cheese... 

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