title: Mild alkali-stable phospholipids in chicken egg yolks: characterization of 1-alkenyl and 1-alkyl-sn-glycero-3-phosphoethanolamine, sphingomyelin, and 1-alkyl-sn-glycero-3-phosphocholine.
abstract: Chicken egg yolk phospholipids were subjected to mild alkaline hydrolysis. The resulting alkali-stable phospholipids were characterized by chemical chromatographic, and enzymatic methods. Two major phospholipids, 1 - O - alkyl - sn - glycero - 3 - pohosphoethanolamine and sphingomyelin; and two minor phospholipids, 1-O-alkenyl-sn-glycero-3-phosphoethanolamine and 1-O-alkyl-sn-glycero-3-phosphocholine; were identified. The sphingomyelins were converted into ceramides by enzymatic hydrolysis with phospholipase C. Ceramides derived from sphingomyelins with non-hydroxy fatty acids (99% of total ceramides) consisted predominantly of the N-palmitoyl, N-stearoyl, and N-nervonyl species. Ceramides derived from sphingomyelins with hydroxy fatty acids (1% of total ceramides) consisted almost exclusively of the N-alpha-hydroxyeicosanoyl species. The long chain bases of ceramides derived from both species of sphingomyelins (hydroxy and non-hydroxy fatty acids) consisted of 97% D-erythro-sphing-4-enine and 3% D-erythro-sphinganine, 1-O-alkyl-sn-glycero-3-phosphoethanolamine and 1-O-alkyl-sn-glycero-3-phosphocholine were converted to corresponding 1-O-alkyldiacetylglycerols. The 1-O-alkyldiacetylglycerols derived from both ether phospholipids consisted largely of the hexadecyl and octadecyl species. Smaller quantities of the heptadecyl, cis-9-octadecenyl and eicosanyl derivatives were also present.
mesh_terms: D000818:Animals; D002417:Cattle; D002518:Ceramides / Q000032:analysis; D002642:Chick Embryo; D002849:Chromatography, Gas; D002850:Chromatography, Gel; D004530:Egg Yolk / Q000032:analysis; D005227:Fatty Acids / Q000032:analysis; D005260:Female; D010713:Phosphatidylcholines / Q000032:analysis*; D010714:Phosphatidylethanolamines / Q000032:analysis*; D013109:Sphingomyelins / Q000032:analysis* / Q000378:metabolism; D010738:Type C Phospholipases / Q000494:pharmacology
chemical_list: D002518:Ceramides; D005227:Fatty Acids; D010713:Phosphatidylcholines; D010714:Phosphatidylethanolamines; D013109:Sphingomyelins; D010738:Type C Phospholipases