Food Chemistry

3.4 Phospho- and Glycolipids 179

Table 3.18.Occurrence of phosphatidyl derivates

Food Lipid P-containing Phosphatidyl derivativesb(mg/kg)
(g/kg) lipidsa(g/kg) PC
PS PE PI

Milk 37. 80. 35 120 10 100 2
Egg 113 35.1 27 , 000 ¾ 5810 ¾
Meat (beef) 19 8. 3 4290 690 1970 ¾
Meat (chicken) 62 6. 6 3320 850 1590 ¾
Tuna fish 155 19. 4 6410 1940 5030 ¾
Potato 1. 10. 56 280 10 160 90
Rice 6. 20. 89 320 30 350 ¾
Soybean 183 17. 8 7980 ¾ 4660 2500

aPhosphatidyl derivatives and other P-containing lipids, e. g., plasmalogens, sphingomyelins.
bThe abbreviations correspond to Formulas 3.26 – 3.29.

OH-group of choline, PC):

(3.26)

Phosphatidyl serine (phosphate group esterified
with the HO-group of the amino acid serine, PS):

(3.27)

Phosphatidyl ethanolamine (phosphate group es-
terified with ethanolamine, PE):

(3.28)

Phosphatidyl inositol (phosphate group esterified
with inositol, PI):

(3.29)

A mixture of phosphatidyl serine and phos-
phatidyl ethanolamine was once referred to as
cephalin.

Examples of foods which contain phosphatidyl

derivatives are shown in Table 3.18. The differ-

ences to the data in Table 3.17 are caused by the

biological range of variations.

Only one acyl residue is cleaved by hydrolysis

(cf. 3.7.1.2.1) with phospholipase A. This yields

the corresponding lyso-compounds from lecithin

or phosphatidyl ethanolamine. Some of these

lyso-derivatives occur in nature, e. g., in cereals.

Phosphatidyl glycerol is invariably found in green

plants, particularly in chloroplasts:

L-α-Phosphatidyl-D-glycerol (3.30)

Cardiolipin, first identified in beef heart, is also

a minor constituent of green plant lipids. Its

chemical structure is diphosphatidyl glycerol:

Diphosphatidyl glycerol (cardiolipin) (3.31)

The plasmalogens occupy a special place in the

class of phospho-glycerides. They are phos-

phatides in which position 1 of glycerol is linked

to a straight-chain aldehyde with 16 or 18 car-

bons. The linkage is an enolether type with a dou-