General Description Bilobalide is a biologically active terpenic trilactone (terpenoid) extracted from Ginkgo biloba . It is synthesized from geranylgeranyl pyrophosphate (GGPP). Application (-)-Bilobalide from Ginkgo biloba leaves has been used as a reference substance to study the antimicrobial activity of different fractions of G.biloba leaves against a number of Gram-positive and negative bacteria and yeasts.