Accentrate® provides EPA and DHA that is conjugated to a phospholipid (PL) just like Vayarin. But instead of phosphatidylserine (PS), Accentrate® contains EPA and DHA that is conjugated to phosphatidylcholine (PC). So the EPA and DHA use PC as the phospholipid carrier to get the EPA and DHA to the brain. (This is why we call it Tissue-Targeted® EPA and DHA.)
What’s the difference between phosphatidylcholine (PC) and phosphatidylserine (PS)?
PS is a phospholipid with a serine molecule bonded to the phosphate group, and PC is a phospholipid with choline bonded to the phosphate group.
PS is synthesized from PC or phosphatidylethanolamine through the exchange of the nitrogen base with free serine in reactions are catalyzed by phosphatidylserine synthase 1 and phosphatidylserine synthase 2 located in the endoplasmic reticulum.
In other words, the body CAN make PS from PC, unlike its inability to synthesize EPA or DHA. But for it to be helpful, the Omega-3s still need to make it to the brain.
 Vayarin Product Insert Note 3. Mozzi, R., S. Buratta, and G. Goracci, Metabolism and functions of phosphatidylserine in mammalian brain. Neurochem Res, 2003. 28(2): p. 195-214.
 Kim, et al., “Phosphatidylserine in the Brain: Metabolism and Function, “Prog Lipid Res. 2014 October.