germacrene-d and artemisia-ketone

Topics: Antioxidants; Artemisia; Artemisia annua; Gas Chromatography-Mass Spectrometry; Monoterpenes; Oils, Volatile; Polycyclic Sesquiterpenes; Russia; Sesquiterpenes, Germacrane

GC and GC-MS analyses of the essential oils of two populations of Artemisia alba Turra, wild-growing on calcareous and serpentine substrates, enabled the identification of 227 different components. Volatile profiles of the two samples differed significantly and only 48 components were in common to both oils. Major constituents of the oils were as follows: germacrene D (38.3%) in the serpentinophyte A. alba (sometimes regarded as A. alba ssp. saxatilis or A. saxatilis) oil and spathulenol (11.8%), artemisia ketone (10.1%), camphor (7.5%) and 1,8-cineole (7.4%) in A. alba (from calcareous habitat) oil. The noted differences were observable on the class level as well: with 73% the sesquiterpenoids (48.2% hydrocarbons, 24.5% oxygen or sulfur containing) were the most abundant compound class in A. saxatilis oil, while the other oil was dominated by monoterpenoids, comprising ca. 60% of the oil (2.1% hydrocarbons and 54.7% oxygenated). Additionally, the serpentinophyte yielded ca. four times less essential oil. These results pointed out to the fact that the type of substrate (soil) could have an important influence on the biosynthesis of A. alba volatiles (genetically predetermined or environmental), especially in the case of populations grown on serpentine rock, characterized by a deficiency of water and indispensable mineral elements.

Topics: Artemisia; Camphor; Chromatography, Gas; Cyclohexanols; Eucalyptol; Gas Chromatography-Mass Spectrometry; Monoterpenes; Oils, Volatile; Sesquiterpenes; Sesquiterpenes, Germacrane

The incorporation of [1-13C]-labeled glucose into the irregular monoterpene artemisia ketone, the regular monoterpenes camphor and beta-thujone, the sesquiterpene germacrene D, the diterpene trans-phytol and beta-sitosterol and isofucosterol has been studied in axenic cultures of Tanacetum vulgare L. (Asteraceae). Quantitative 13C NMR spectroscopic analysis of the resulting labeling patterns showed that the isoprene units of the monoterpenes and the diterpene are formed via the methylerythritol phosphate (MEP) pathway, whereas the isoprene building blocks of the sesquiterpene and the sterols originate from the mevalonic acid (MVA) pathway.

Topics: Bicyclic Monoterpenes; Camphor; Diterpenes; Magnetic Resonance Spectroscopy; Monoterpenes; Sesquiterpenes, Germacrane; Sitosterols; Stigmasterol; Tanacetum; Terpenes