Terpenoids ginkgo

Selective Elution of Flavonoids from Terpenoids in Ginkgo biloba Leaf Extracts... 

Pietri S, Maureiii E, Drieu K, Cuicasi M. (1997). Cardioprotective and antioxidant effects of the terpenoid constituents of Ginkgo biioba extract (EGb 761). J Mol Cell Cardiol. 29(2) 733-42. 

After administration of EGb 761 extract (24% ginkgo-flavone glycosides and 6% terpenoids). 

After administration of milligram Ginkgoselect Phytosome formulation (24% ginkgo-flavone glycosides and 6% terpenoids in phospholipid complex, 1 2). Abbreviations. N, number of subjects i.v., intravenous C ax, maximum plasma concentration tmux, time at ti/2(p), elimination half-life CL/F, clearance with regard to bioavailability F/F, volume of distribution with regard to bioavailability. 

Ginkgo biloba extract is prepared from the leaves of the ginkgo tree. The most common formulation is prepared by concentrating 50 parts of the crude leaf to prepare one part of extract. The active constituents in ginkgo are flavone glycosides and terpenoids (ie, ginkgolides , , C, J, and bilobalide). 

Mauri, R Migliazza, B. Pietta, P. Liquid chromatography/electrospray mass spectrometry of bioactive terpenoids in Ginkgo biloba L. J. Mass. Spec., 1999, 34 1361-1367. 

Liebgott, T. Miollan, M. Berchadsky, Y. Drieu, K. Culcasi, M. Pietri, S. Complementary cardioprotective effects of flavonoid metabolites and terpenoid constituents of Ginkgo biloba extract (EGb 761) during ischemia and reperfusion. Basic Res. Cardiol, 2000, 95 368-377. 

The existence of a similar non-mevalonate route to terpenoids in plants was first reported in 1994. When Duilio Arigoni and co-workers fed different C-labelled forms of glucose to Ginkgo biloba embryos, the G-nuclear magnetic resonance (NMR) spectra of the resulting diterpenes were not what would have been expected from the normal operation of the mevalonate pathway (Cartayrade et al, 1994), but showed an incorporation pattern identical to that seen with the E. coli terpenoids. Subsequent studies employing... 

Cartayrade, A., Schwarz, M., Jaun, B. and Arigoni, D. (1994) Detection of two independent mechanistic pathways for the early steps of isoprenoid biosynthesis in Ginkgo biloba, in Second Symposium of the European Network on Plant Terpenoids. Strasbourg, France. 

The effects of GB are attributed to several chemical constituents of the whole plant rather than to any one individual component. These chemicals include many flavonoids (also called flavonol, flavone, or flavonoid glycosides, ginkgo flavone glycosides, dimeric bioflavones), and the terpene lactones (also called terpenoids, diterpenes, terpenes), including the ginkgolides and bilobalide (2,5-7). 

Nature Prepared from the leaves of Ginkgo hiloha, ginkgo contains flavone glycosides and terpenoids. 

The effect of EGb 761 on GSH homeostasis in cultured human kerationcytes (HaCaT) has recently been studied [60]. HaCaT were incubated with EGb 761, some of its purified flavonoids (quercetin, kaempferol, rutin), or terpenoids (gingkolides A, B, C, J, bilobalide) for up to 72 hours. Incubation of HaCaT with the purified flavonoids or terpenoids had no effect on cellular GSH levels. However, EGb 761 treatment (up to 200 pg/mL) resulted in dose-dependent increases in cellular GSH. Ginkgo biloba subfractions lacking terpenoids (CP205) or both terpenoids and flavonoids (HE215) caused a similar increase in cellular GSH to that of EGb 761, indicating that flavonoids and terpenes in the extract may not be responsible for augmentation of intracellular GSH. 

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