Sample Preparation of Standardized Extracts of Ginkgo biloba by Supercritical Fluid Extraction

✍ Scribed by Teris A. van Beek; Larry T. Taylor

• Publisher: John Wiley and Sons
• Year: 1996
• Tongue: English
• Weight: 739 KB
• Volume: 7
• Category: Article
• ISSN: 0958-0344
• DOI: 10.1002/(sici)1099-1565(199607)7:4<185::aid-pca302>3.0.co;2-u

✦ Synopsis

A method of sample preparation of standardized extracts of Ginkgo biloba using supercritical fluid extraction (SFE) is described. Ginkgolides and bilobalide could be selectively extracted with carbon dioxide containing 10 % methanol at 335 atm and 45 "C from a methanolic solution of the extract. An in-line filter of silica gel was found to be essential for obtaining clean samples. Trapping was carried out with a solid silica gel trap at 80 "C. After eluting the trap with methyl acetate, the sample could be analysed by gas liquid chromatography or high performance liquid chromatography. Recoveries of the five terpenes relative to a standard solid phase extraction (SPE) procedure varied for two different extracts from 98.6 to 102.3%. Relative standard deviations were better for SFE than for SPE. A further advantage of the SFE over the SPE method is that it is much less laborious. A disadvantage is that it requires an automated supercritical extractor. With a small adaptation, the SFE method could also be used for finished ginkgo drugs in an aqueous alcoholic solution.