In vitro studies indicate that miquelianin (quercetin 3-O-beta-D-glucuronopyranoside) is able to reach the CNS from the small intestine.

Miquelianin (quercetin 3-O-beta-D-glucuronopyranoside) is one of the flavonoids of St. John's wort (Hypericum perforatum L.) whose antidepressant activity has been shown by the forced swimming test, an in vivo pharmacological model with rats.

New and known iridoid- and phenylethanoid glycosides from Harpagophytum procumbens and their in vitro inhibition of human leukocyte elastase.

Ten compounds, harpagoside (1), 8- p-coumaroylharpagide (2), 8-feruloylharpagide (3), 8-cinnamoylmyoporoside (4), pagoside (5), acteoside (6), isoacteoside (7), 6'- O-acetylacteoside (8), cinnamic acid (9) and caffeic acid (10) were isolated from the storage roots of Harpagophytum procumbens, Pedaliaceae. Compounds 1, 2, 6, 7 and 9 are known for H. procumbens; 3 and 10 were isolated the first time from H.