|Dong quai contains seven coumarin derivatives, which are capable of dilating vessels, stimulating the uterus and the central nervous system (osthol), and fighting spasms. Linear furanocoumarins, however, such as the constituent bergapten (5-methoxypsorlen), imperatorin, and psoralen, ingested in large quantities, are prone to cause photosensitization which may result in dermatitis.|
Dong quai also produces an essential oil which contains the spasmolytic lactones angelicide, butylidenephthalide, butylphthalide and ligustilide; safrole and isosafrole, as well as the analgesic and anti-inflammatory phenylpropanoid, ferulic acid, and the ubiquitous phytosterol, â-sitosterol. Additionally present in the essential oil is a varied assortment of monoterpenes and sequiterpenes, including cadinene and carvacrol, as well as n-dodecanol, n-tetradecane and n-tetradecanol. The vasodilative nicotinic acid has also been reported.
Vitamin B12 is found in the dried root in significant amounts (0.25 to 0.4 mcg/100 grams of dried root), in addition to folic acid, folinic acid and nicotinic acid, found in the root; also reported are lesser quantities of vitamins A and E, biotin, carotene and pantothinic acid. 8 This may partially explain the beneficial effects of dong quai on anemia.