Studies on the Origin of (-)-alpha-Bisabolol and Chamazulene in Chamomile Preparations; Part I. Investigations by Isotope Ratio Mass Spectrometry (IRMS).
IRMS was used to determine the delta (13)C-and deltaD-values of dried plant material and essential oil fractions of CHAMOMILLA RECUTITA and VANILLOSMOPSIS ERYTHROPAPPA and of isolated components thereof. Both plants turned out to follow the same C (3) photosynthetic pathway. The carbon isotope ratios ( delta (13)C-values) of chamomile-derived bisabolol ranged from -32 per thousando to -30 per thousand; the corresponding deltaD-values varied between -240 per thousand and -205 per thousand. VANILLOSMOPSIS bisabolol differed significantly, with delta (13)C-values of approximately -27 per thousand, and a deltaD-value of about -175 per thousand. In addition, chamazulene of chamomiie was characterized by a delta (13)C-value of -31 per thousand, whereas in chamazulene from ACHILLEA MILLEFOLIUM lower carbon discrimination was found (delta (13)C = -30 per thousand). The delta (13)C-values allowed us to detect adulterations of chamomiie preparations. The isolation of bisabolol, a main ingredient of these preparations, and subsequent IRMS analysis is much more tedious than GC/IRMS, which makes it possible to determine the carbon isotope ratio of bisabolol without prior isolation. Only one commercial chamomiie preparation was completely free of non-chamomile admixtures. Our investigations clearly demonstrate that admixtures of natural compounds can be detected in chamomile oil and chamomile preparations even if there is no difference in the photosynthetic mechanism of the corresponding plants.
Carle
R
R
Pharma-Forschung der ASTA Pharma AG, Weismüllerstraße 45, D-6000 Frankfurt/Main, Federal Republic of Germany.
Fleischhauer
I
I
Beyer
J
J
Reinhard
E
E