Valerian (herb) particular binding site. Hydrophilic extractions of the herb commonly sold over the counter, however, probably do not contain significant amounts of isovaltrate. Valerenic acid in valerian stimulates serotonin receptors as a partial agonist, including 5-HT which is implicated in the sleep-wake cycle. The chief constituent of valerian is a yellowish-green to brownish-yellow oil present in the dried root, varying in content from 0.5 to 2.0%. This variation in quantity may be determined by location; a dry, stony soil yields a root richer in oil than moist, fertile soil. The volatile oils that form the active ingredient are pungent, somewhat reminiscent
Valerenic acid Valerenic acid Valerenic acid is a sesquiterpenoid constituent of the essential oil of the Valerian plant. Valerian is used as a herbal sedative which may be helpful in the treatment of insomnia. It is likely that several components of the plant contribute to the effect. Valerenic acid is thought to be at least partly responsible for the sedative effects. Valerenic acid acts as a subtype-selective GABA receptor positive allosteric modulator via a binding site in the transmembrane domain at the βα interface. At receptors expressed in Xenopus oocytes (frog eggs) it was shown that only assemblies incorporating β2 or β3