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Comparison of Extraction Methods for the Analysis of Ginkgo biloba Leaves and Ginkgo-Containing Tablets
Published
Author(s)
S. Howerton, Kate Rimmer, Lane C. Sander
Abstract
In preparation for the certification of three Standard Reference Materials containing Ginkgo biloba, three extraction techniques are compared. For the three flavonoid aglycones (quercetin, isorhamnetin, and kaempferol) Soxhlet extraction and pressurized fluid extraction are quantitatively compared using an internal standard approach. In addition the hydrolysis of the glycosides to the flavonoid aglycones is reported as a function of acid concentration and time. For the terpene trilactones (Ginkolides A, B, C, J and bilobalide) Soxhlet extraction, sonication, and pressurized fluid extraction are quantitatively compared using an internal standard approach. The data demonstrate that the two methods for the aglycones are statistically equivalent, and that the optimal hydrolysis conditions require reflux with 25% HCl (mass fraction) for three hours. The data also indicate that Soxhlet extraction and sonication are the preferred methods for the quantitative determination of the terpene trilactones.
Howerton, S.
, Rimmer, K.
and Sander, L.
(2021),
Comparison of Extraction Methods for the Analysis of Ginkgo biloba Leaves and Ginkgo-Containing Tablets, Journal of Chromatography A
(Accessed October 10, 2025)