NOW&ampreg; Phosphatidyl Serine with Ginkgo Biloba combines two powerful nutrients that work synergistically with one another. Phosphatidyl Serine is a naturally occurring phospholipid compound derived from soy lecithin that plays an essential role in cellular composition.&ampnbsp; Ginkgo Biloba is a popular herbal extract that has demonstrated powerful antioxidant activity in in vitro studies.*