Terpene trilactones

Both human and animal pharmacokinetic studies have been done on ginkgo flavonol aglycones (quercetin, kaempferol, and isorhamnetin) and terpene trilactones (ginkgolide A and B and bilobalide). 

It is not understood which components of EGb 761 are efficacious, but it is assumed that the major components flavonoids and terpene trilactones play important roles. However, when dealing with effects in the CNS, it is assumed that the flavonoids do not penetrate the blood-brain barrier whereas it has been... 

Strpmgaard, K. Nakanishi, K. Chemistry and biology of terpene trilactones from Ginkgo biloba. Angew. Chem. Int. Ed., 2004, 43 1640-1658. 

Mauri, R Simonetti, R Gardana, C. Minoggio, M. Morazzoni, R Bombardelb, E. Rietta, R. Liquid chromatography/atmospheric pressure chemical ionization mass spectrometry of terpene trilactones in plasma of volunteers dosed with Ginkgo biloba L. extracts. Rapid Commun. Mass Spec., 2001, 15 929-934. 

High-performance liquid chromatography was the first method of choice for the nonvolatile terpenes as terpene trilactones. The analysis is performed by RP-HPLC on Cig with isocratic development either in methanol-water or methanol-water-THF. Detection can be carried out by UV (taking into consideration poor UV absorption of the compounds), Rl, ELSD, or MS. 

Chemistry and biology of terpene trilactones from Ginkgo Biloba 04AG(E)1640. 

Raising pressure at a fixed temperature improves the extraction efficiency due to an increased fluid density. In the extraction of bilobalide and ginkgolides, the maximum extraction efficiency was achieved when the density was at least 0.72 g/mL. Because the extraction of bilobalide and ginkgolides is improved at elevated temperature, high pressures are requited to olMain the minimum needed density. At the optimal temperature (100 °C), a density of 0.72 g/mL was obtained at 350 atm pressure. With the qitimized conditions (ethanol/acetic acid as a modifier, 100 °C and 330 atm), quantitative extraction of terpene trilactones from Ig sample of Ginkgo biloba was achieved with 20 min static and 20 min dynamic extraction times (two times of SFE). Under... 

The SFE technique was compared to the boiling liquid methods performed with the following solvents 1) acetone, 2) ethanol, 3) methanol, 4) water, and 5) water/methanol (70 30 vfv). The SFE method showed the highest extraction efficiency and reproducibility (RSD<5%, n = 3) for removing terpene trilactones from the ginkgo leaves in comparison with the solvent extraction methods. The total efficiencies for recovety of bilobalide and gingkolides (A, B, and C) with the solvent based methods were 60 91% relative to the SFE results (Table I). 

Akita, H. et al.. Identity of aabomycin A with venturicidins, Agric. Biol. Chem., 54, 2465, 1990. Stromgaard, K. and Nakanishi, K., Chemistry and biology of terpene trilactones from Ginkgo biloba, Angew. Chem., Int. Ed. Engl., 43, 1640, 2004. 

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