NOW Double Strength Ginkgo Biloba is the finest quality available worldwide. Scientific research has demonstrated that Ginkgo Biloba Extract has antioxidant activity in in vitro studies. NOW Ginkgo Biloba is grown and extracted under the highest quality standards and is standardized to min. 24% ginkgoflavonglycosides and min. 6% terpene lactones including ginkgolide B the most significant fraction and ginkgolides A C and bilobalide. Not manufactured with yeast wheat gluten soy milk egg fish shellfish or tree nut ingredients.