Phosphatidylserine

Phosphatidylserine (PS) is a phospholipid component of cell membranes, most abundant in the phospholipid bilayer of neuronal cells. It functions primarily as a structural element that maintains membrane fluidity and participates in signal transduction, particularly in the brain where it supports the integrity of synaptic membranes and facilitates neurotransmitter activity.

• Molecular Formula & Name: Phosphatidylserine is a glycerophospholipid with the molecular formula C₁₃H₂₆NO₁₀P. Its IUPAC name is (2‑S‑(3‑hydroxy‑2‑methyl‑propyl)‑1‑(2‑hydroxy‑3‑(2‑hydroxy‑1‑oxo‑2‑p‑hydroxy‑2‑methyl‑propyl)‑? (the full IUPAC name is extensive and typically abbreviated as PS).
• Structure: The molecule consists of a glycerol backbone esterified at the sn‑1 and sn‑2 positions with fatty acid chains (commonly 16:0/18:1 or 18:0/20:4) and a phospho‑serine headgroup at the sn‑3 position.
• Charge & Function: The headgroup carries a net negative charge at physiological pH, facilitating interactions with positively charged protein domains.
• Properties: Its amphiphilic nature enables incorporation into bilayer membranes, influencing fluidity and curvature.
• Melting Point & Solubility: PS has a melting point around 55 °C (depending on fatty acid composition) and is soluble in organic solvents (chloroform, methanol) but poorly soluble in water, necessitating lipid‑based delivery systems for oral supplements.

• Natural Sources: Natural sources of phosphatidylserine include bovine brain tissue (historically) and soy, sunflower, or rapeseed phospholipid extracts.
• Commercial Production: Modern commercial PS is primarily derived from soy lecithin or sunflower seed phospholipids through enzymatic de‑acylation and re‑esterification processes that enrich the serine headgroup.
• Purification: High‑purity (>95 %) PS is obtained by chromatographic purification to remove phosphatidylcholine and other contaminants.
• Consumer Considerations: For vegan or allergen‑sensitive consumers, non‑animal, non‑genetically‑modified (non‑GMO) soy or sunflower-derived PS is preferred.
• Quality Control: Quality considerations include verifying the phosphatidylserine content by HPLC, absence of heavy metals, and compliance with Good Manufacturing Practices (GMP). The presence of residual phosphatidic acid or phosphatidylinositol should be minimal (<1 %) to ensure product potency and safety.