Pg. Pietta et al., IDENTIFICATION OF GINKGO-BILOBA FLAVONOL METABOLITES AFTER ORAL-ADMINISTRATION TO HUMANS, Journal of chromatography B. Biomedical sciences and applications, 693(1), 1997, pp. 249-255
Citations number
6
Categorie Soggetti
Chemistry Analytical","Biochemical Research Methods
An extract of Ginkgo biloba leaves (EGb) was given to healthy voluntee
rs. Urine samples were collected for 3 days, and blood samples were wi
thdrawn every 30 min for 5 h. The samples were purified through SPE C-
18 cartridges and analyzed by reversed-phase LC-diode array detection
for the presence of EGb metabolites. Only urine samples contained dete
ctable amounts of substituted benzoic acids, i.e., 4-hydroxybenzoic ac
id conjugate, 4-hydroxyhippuric acid, 3-methoxy-4-hydroxyhippuric acid
, 3,4-dihydroxybenzoic acid, 4-hydroxybenzoic acid, hippuric acid and
3-methoxy-4-hydroxybenzoic acid (vanillic acid). In contrast to rats n
o phenylacetic acid or phenylpropionic acid derivatives were found in
urine, thus indicating that in humans a more extensive metabolism take
s place. As for rats the metabolites found in human urines accounted f
or less than 30% of the flavonoids given. The same procedure was appli
ed to blood samples, and no metabolites could be detected.