Ginkgo Biloba Extract (GBE)


Ginkgo biloba extract and two ingredients, bilobalide and ginkgolide B, are presented to the CSWG as part of a review of botanicals being used as dietary supplements in the United States. ( 1 of 3 adults in the United States are now taking dietary supplements ). Sweeping deregulation of botanicals now permits Ginkgo biloba extract to be sold as a dietary supplement to a willing public eager to improve brain functioning or promote radical scavenging activity.

Ginkgo biloba extract is a well defined product, and it or its active ingredients, the ginkgolides, especially ginkgolide B, and bilobalide, have clearly demonstrated biological activity. It can be consumed in rather large doses for an extended period of time.

Standardized ingredients of Ginkgo biloba extract

The extract utilized in medicine is standardized in a multi-step procedure designed to concentrate the desired active principles from the plant. These extracts contain approximately 24% flavone glycosides (primarily composed of quercetin, kaempferol, and isorhamnetin) and 6% terpene lactones (2.8-3.4% ginkgolides A, B, and C, and 2.6-3.2% bilobalide). Ginkgolide B accounts for about 0.8% of the total extract, and bilobalide accounts for about 3% of the extract. Other constituents include proanthocyanadins, glucose, rhamnose, organic acids, D-glucaric acid and ginkgolic acid (at most 5 ppm ginkgolic acids). Much of the curative properties of Ginkgo biloba extract are due to the activities of these flavonoids.