Chamomile is one of the most ancient medicinal herbs known to mankind. It is a member of Asteraceae/Compositae familyTwo types of chamomile are used for good health: German chamomile (Matricaria retutica) and Roman (or English) chamomile (Chamaemelum nobile).
Chamomile are native in many countries throughout Europe, and are cultivated in such countries as Germany, Egypt, France, Spain, Italy, Morocco, and parts of Eastern Europe. The various different Chamomile plants are very distinct and require their own set of conditions to grow. For example, Roman chamomile is a perennial plant (meaning it will live more than two years). It grows close to the ground and has smallish blossoming flowers. It tends to be bitter when used in teas. German chamomile, on the other hand, is a sweeter variety. It is an annual plant and can grow large blossoms up to three feet in height.
When exposed to steam distillation, the oil ranges in color from brilliant blue to deep green when fresh but turns to dark yellow after storage. Despite fading, the oil does not lose its potency. Approximately 120 secondary metabolites have been identified in chamomile, including 28 terpenoids and 36 flavonoids . The principal components of the essential oil extracted from the German chamomile flowers are the terpenoids α-bisabolol and its oxide azulenes including chamazulene and acetylene derivatives. Chamazulene and bisabolol are very unstable and are best preserved in an alcoholic tincture. The essential oil of Roman chamomile contains less chamazulene and is mainly constituted from esters of angelic acid and tiglic acid. It also contains farnesene and α-pinene. Roman chamomile contains up to 0.6% of sesquiterpene lactones of the germacranolide type, mainly nobilin and 3-epinobilin. Both α-bisabolol, bisabolol oxides A and B and chamazulene or azulenesse, farnesene and spiro-ether quiterpene lactones, glycosides, hydroxycoumarins, flavanoids (apigenin, luteolin, patuletin, and quercetin), coumarins (herniarin and umbelliferone), terpenoids, and mucilage are considered to be the major bio-active ingredients . Other major constituents of the flowers include several phenolic compounds, primarily the flavonoids apigenin, quercetin, patuletin as glucosides and various acetylated derivatives. Among flavonoids, apigenin is the most promising compound. It is present in very small quantities as free apigenin, but predominantly exists in the form of various glycosides
The pollen found in chamomile preparations may cause allergic reactions. If you are allergic to ragweed pollen, you may not be able to use chamomile. Chamomile may interfere with blood thinners (anticoagulants).