New terpenoids in cultivated and wild chamomile (in vivo and in vitro)

Abstract

The effect of Chamomilla recutita (L.) Rauschert is made up by several groups of active substances, among which terpenoids in the inflorescences are of greatest importance. Among cultivated species, the Hungarian BK-2 contains more chamazulene in its essential oil than the German Degumil type, which is mainly cultivated for its (−)-α-bisabolol. Both components have important antiinflammatory activities. Among wild chamomile populations in Hungary, a population was found in the area of Szabadkigyós containing significant amounts—on average 48%—of (−)-α-bisabolol in its inflorescence oil. In vitro cultures were made from this population to obtain propagation material containing a high number of active substances. The intact roots contained no (−)-α-bisabolol but the sesquiterpene alcohol β-eudesmol as new compound was identified by our group. Sterile plantlets, cultured in vitro, were multiplied for phytochemical investigations. Pharmacologically important compounds of the essential oils were followed in great detail. The amount of in vitro cultured terpenoids and polyin compounds was compared with that of in vivo plants. These volatile compounds were identified by comparing their retention times with those of authentic standards, essential oils of known composition and peak enrichment. The confirmation of identity was done by comparison of their mass spectra with those reported in the literature and reference compounds. The percentage evaluation of each component was made by area normalisation. Gas chromatography (GC) and mass spectrometry (MS) showed that sterile chamomile cultures generated the most important terpenoid and polyin compounds characteristic of the parent plant. We identified germacrene-D, berkheyaradulene, 4-(2′, 4′, 4′-trimethyl-bicyclo[4.1.0]hept-2′-en-3′-yl)-3-buten-2-one, geranyl-isovalerate and cedrol as new components in these sterile cultures.