Brain Health Soy-Free Sharp-PS Non-GMO A Dietary Supplement Vegetarian/Vegan General Health Family Owned Since 1968 GMP - Quality Assured Phosphatidyl serine (PS) is a natural compound that’s an important component of cell membranes, where it plays an essential role in communication and the transfer of nutrients between cells. Derived from non-GMO sunflower lecithin, NOW Soy-Free Sunflower Phosphatidyl Serine supports brain health, nervous system function, and the activity of neurotransmitters involved in learning, memory, and mood.