Methoxyflavone Standardization & Grades
Polymethoxyflavones are flavones in which most of the hydroxyl groups are replaced by methoxy groups. The three main members in black ginger are 5,7-dimethoxyflavone, 5,7,4′-trimethoxyflavone and 3,5,7,3′,4′-pentamethoxyflavone. The methoxy groups make these molecules fat soluble, which is why ethanol extracts them and water does not. The grade names the total of these compounds and not a single member. The botanical entity is Kaempferia parviflora Wall. ex Baker, a plant of the Zingiberaceae native to Thailand, and the part used is the rhizome.
The grade is a single level at 10%, so there is no tier to choose between. The choice is between rhizome materials. Black ginger is also supplied as a 10:1 ratio extract, the Black Ginger Extract Powder, which carries no marker figure. The standardized extract is a concentrate of the flavone fraction, and the data for this product lists 5,7-dimethoxyflavone as a secondary marker that is read beside the total. Black ginger is a different plant from ordinary ginger and from kencur, and none of the three is a substitute for another. Black ginger extract at 10% is a flavone concentrate, and the grade describes that fraction only, not the whole rhizome.












