Simultaneous quantification of terpenelactones and flavonol aglycones in hydrolyzed ginkgo biloba extract by liquid chromatography with inline ultraviolet and evaporative light scattering detection.
We report here a liquid chromatography (LC) method with inline ultraviolet/evaporative light scattering (UV/ELS) detection for the simultaneous quantification of the terpenelactones and flavonol aglycones in a single sample of hydrolyzed Ginkgo biloba extract (GBE). The sample is hydrolyzed by a rapid and convenient oven heating method for 1 h at 90 degrees C with 10% hydrochloric acid. The 1 h hydrolysis was found to be equivalent to the 2.25 h reflux treatment for dry powder extract, where total flavonol glycosides were 28.4 and 28.1%, respectively. Acceptable precision was achieved for total terpenelactones [relative standard deviation (RSD) = 4.8%] by ELS detection, and total flavonol aglycones (RSD = 2.3%) by UV detection. The analytical range was 1.5 to 7.3% (w/w) for the individual terpenelactones (ELS) and 2.5 to 15.0% (w/w) for the individual glycosides (UV) calculated from the aglycones quercetin, kaempferol, and isorhamnetin. This improved method allows for the first time high throughput sample preparation coupled with the quantification of the predominant compounds generally used for quality control of GBE in a single assay.
Gray
Dean E
DE
Midwest Research Institute, 425 Volker Blvd, Kansas City, MO 64110-2299, USA. dgray@mriresearch.org
Messer
Dale
D
Porter
Andrew
A
Ferguson
Sherry
S
Harris
Roger K
RK
Clark
Alice P
AP
Algaier
Joseph W
JW
Overstreet
J Diane
JD
Smith
Cynthia S
CS
D002845:Chromatography; D002853:Chromatography, Liquid / Q000379:methods*; D044948:Flavonols / Q000032:analysis*; D020441:Ginkgo biloba / Q000378:metabolism*; D006027:Glycosides / Q000032:analysis / Q000737:chemistry; D006358:Hot Temperature; D006851:Hydrochloric Acid / Q000032:analysis; D006868:Hydrolysis; D007477:Ions; D044949:Kaempferols / Q000032:analysis; D007783:Lactones / Q000032:analysis*; D008027:Light; D008956:Models, Chemical; D004364:Pharmaceutical Preparations / Q000737:chemistry; D010936:Plant Extracts / Q000032:analysis*; D011786:Quality Control; D011794:Quercetin / Q000032:analysis / Q000031:analogs & derivatives; D015203:Reproducibility of Results; D012542:Scattering, Radiation; D013056:Spectrophotometry, Ultraviolet; D013696:Temperature; D013729:Terpenes / Q000032:analysis*; D013997:Time Factors; D014466:Ultraviolet Rays
D044948:Flavonols; D006027:Glycosides; D007477:Ions; D044949:Kaempferols; D007783:Lactones; D004364:Pharmaceutical Preparations; D010936:Plant Extracts; D013729:Terpenes; C047368:3-methylquercetin; C006552:kaempferol; D011794:Quercetin; D006851:Hydrochloric Acid