Nonenzymic browning. XIV. Reaction of phospholipids with 1,4-benzoquinone.
Phosphatidylethanolamine reacts with 1,4-benzoquinone with the formation of a red unstable intermediary product consisting of one phosphatidylethanolamine residue and one 1,4-benzoquinone residue. The secondary reaction products are purple, violet, and reddish brown. Consequently, the absorption maximum shifts from 430 nm to 490 nm during the reaction. Finally, brown macromolecular end-products are formed. Phospholipids derived from choline, such as phosphatidylcholine, lysophosphatidylcholine, sphingomyelin, contribute only a little to the browning reactions, in comparison with phospholipids containing a primary amino-group (phosphatidylethanolamine, lysophosphatidylethanolamine, phosphatidylserine). The browning of a natural mixture of egg phospholipids depends on the content of derivatives containing a primary amino-group.
D000042:Absorption; D003116:Color; D046911:Macromolecular Substances; D010713:Phosphatidylcholines; D010714:Phosphatidylethanolamines; D010718:Phosphatidylserines; D010743:Phospholipids; D011809:Quinones; D013109:Sphingomyelins
D046911:Macromolecular Substances; D010713:Phosphatidylcholines; D010714:Phosphatidylethanolamines; D010718:Phosphatidylserines; D010743:Phospholipids; D011809:Quinones; D013109:Sphingomyelins