Egg yolk phospholipids

Fig. 5 Relationship between the log Ks values obtained by chromatography on entrapped egg yolk phospholipid (EPL) liposomes and the log Poct values from oc-tanol/water partitioning analyses, for neutral drugs (upper line) and for positively (center line) and negatively (lower line) charged drugs. (Reprinted with permission from Ref. 27. Copyright 2001 Elsevier Science.)...

A typical feature that tells the importance of the backbone of phospholipid molecule which DHA bounds is the prevention effect on apoplexy. A combination of phosphoryl base group with DHA must be crucial to exert antiapoplexy function as shown in Fig. 3.1. Among fish oil TG, egg yolk phospholipid, and squid phospholipid which is rich in sn-2... 

To act as solubilizing, wetting, or emulsifying agents such as Cremophor EL, sodium desoxy-cholate, Polysorbate 20 or 80, PEG 40 castor oil, PEG 60 castor oil, sodium dodecyl sulfate, lecithin, or egg yolk phospholipid. 

Fat emulsions are used to supply a large amount of energy in a small volume of isotonic liquid they supply the body with essential fatty acids and triglycerides. Fat emulsions for intravenous nutrition contain vegetable oil and phospholipid emulsifier. Several commercial fat emulsions are available, such as Intralipid, Lipiphysan, Lipofundin and Lipo-fundin S. They contain either cottonseed oil or soybean oil. In Intralipid, for example, purified egg-yolk phospholipids are used as the emulsifiers, and isotonicity is obtained by the addition of sorbitol, xylitol or glycerol. Intralipid has also been used as the basis of an intravenous dmg carrier, for example for diazepam (Diazemuls) and propofol (Diprivan), as an alternative to solubilisation in nonionic micellar systems such as Cremophor EL. 

The PFCs are formulated as stable aqueous emulsions with dextrose, egg yolk phospholipids, and physiologic electrolytes. These emulsions are somewhat less viscous than whole blood at 37°C. The PFCs have a dose-dependent half-live of 8 to 24 hours. Normal doses are 10 mL/kg, but short-term doses of up to 30 mL/kg have been reported. The PFCs are not metabolized and are eliminated unchanged in expired respiratory gases. Because they are highly lipophilic, multiple doses can cause PFC accumulation in the liver and spleen. Therefore, it is recommended that these compounds not be administered more than once in a 6-month period. 

Mayonnaise (Figure 2.21) is an OAV emulsion consisting of 50 to 85% edible oil, 5 to 10% egg yolk, vinegar, salt, and seasonings. The emulsion is stabilized by egg yolk phospholipids. Tung and Jones (1981) studied the mayonnaise microstructure by conventional SEM and observed a high concentration of dispersed phase... 

Phospholipids from animal sources, mainly egg yolk phospholipids, are very expensive thus, they are used only for pharmaceutical purposes or for biochemical research. 

In contrast to the wealth of information pertaining to the characteristics of soy and egg yolk phospholipid liposomes, almost nothing has been reported on the characteristics and especially the functionalities of docosahexaenoic acid (DHA)-inserted phospholipid liposomes. The exception was a paper describing the antitumor properties of n-3 fatty acid-containing liposomes against the myeloid leukemia T27A (1). 

The development of an amphotericin B microcmulsion for the treatment of ocular mycosis was reported in 1996 by Cohen et al. (39). The vehicle was prepared with Intralipid 20%. an intravenous fat emulsion marketed by Pharmacia and Upjohn, containing soybean oil and egg yolk phospholipids. The emulsion. 

Fig. 5 Frequency shift of the P=0 synunetric stretching band in spectra of PE-lecithin mixtures in the absence of added water (1) and in the presence of 4 water molecule per lecithin molecule (2) vs. mole fraction of PE. The net concentration of egg yolk phospholipids in n-decane was 40 mg/ml...

Bromoperfluorooctane emulsified with egg-yolk phospholipids as a surfactant did not exhibit any toxic effects in the liver, spleen, and bone marrow [85]. 

The surfactants used in the first-generation fluorochemical blood substitutes were ordinary soaps (potassium oleate), egg-yolk phospholipids (lecithin), or Pluronic F-68. These emulsifiers were used individually or as their mixtures. 

Perfluoroalkylated phosphotidylcholines [150-153] are more effective emulsifiers for fluorocarbons than the natural egg-yolk phospholipids. Concentrated [50% (w/v)] perfluorodecalin emulsions containing only 1% surfactant... 

Meinert et al. [104-106] found that already small quantities [1 or 2% (w/v)] of partially fluorinated alkanes, C, F2 ,+ iC H2h+i, stabilize perfluorodecalin-Pluronic F68 emulsions. Riess et al. [130] deseribed a binary emulsifier system, consisting of a nonfluorinated surfactant in conjunction with a partially fluorinated alkene. Riess et al. [130] named the fluorinated amphiphile a dowel," suggesting that its fluorophilic end adsorbs in the fluorocarbon surface and its lipophilic end penetrates the lipophilic part of the egg-yolk phospholipid. The dowel, C8Fi7CH=CHCsHi7, increased the stability of a perfluorooctyl bromide (PFOB)-egg-yolk lipid emulsion stability considerably. The droplet size (0.25, m) remained constant over 9 months, even at 40 C. In the absence of the dowel, the droplet size more than doubled at 25 C to 0.49 jum. 

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