Essential oils chiral compounds analysis

D. Bartschat, D. Lehmann, A. Dietrich, A. Mosandl and R. Kaiser, Chiral compounds of essential oils. XIX. 4-methyl-5 decanolide chirospecific analysis, structure and properties of the stereoisomers , Phytochem. Anal. 6 130-134 (1995). 

Schubert, V. and Mosandl, A. (1 991) Chiral compounds of essential oils. VIII. Stereo differentiation of linalool using multidimensional gas chromatography. Phytochemical Analysis 2, 1 71-1 74. 

C. Askari, P. Kreis, A. Mosandl and H.-G. Schmarr. Chiral Compounds of Essential Oils Vll Quality Evaluation of Mentha Oils, using enantioselective CGC-Analysis of Monoterpenoid Constituents. Arch. Pharm., 325, 35-39 (1992). 

Table 1 GCxGC and GCxGC-MS analysis of plant extracts, essential oils, and chiral compounds... 

Kreis P. Mosandl, A. (1993). Chiral compounds of essential oils. Part XIII. Simultaneous chirality evaluation of geranium oil constituents. Flavour and Fragrance Journal, Vol.8, No.3, (May/June 1993), pp. 161-168, ISSN 1099-1026 Lancas, F. M. Cavicchioli M. (1990). Analysis of the essential oils of Brazilian citrus fruits by capillary gas chromatography. Journal of High Resolution Chromatography, Vol.l3, No.3, (March 1990), 207-209, ISSN 0935-6304... 

Numerous components are offered on the market like citral from Litsea cubeba oil, geraniol from palmarosa oil, linalool from ho oil, coriander oil or lavandin, pinenes from different Pinus species, citronellal from Corymbia citriodora, cedrol from cedarwood, or even the santalols from different sandalwood species. All these are added to nish essential oils. As already mentioned before, synthetic chemicals can no more be applied as enantiomeric separation is a state of the art today and will convict the matter of fact of adulteration. By using synthesized, correct chiral compounds, the detection is hardly to be recognized but with NMR method, but this is an expensive analysis. 

ISO standard 21093 shows character and data for this oil. In the past, addition of turpentine oil was used for adulteration later the essential oil of the needles of Pinus maritima was used, as the composition showed very close data of compounds. Chiral analysis gives helpful results. Kreis et al. (1991) reported chiral ratio in monoterpenes as follows (lR,5R)-(+)-a-pinene (44%) (15,55)-(-)-a-pinene (56%) (lR,5R)-(+)-p-pinene (2%) (15,55)-(-)-p-plnene (98%) and (47 )-(+)-limonene (40%) (45)-(-)-limonene (60%). 

Chiral compounds are frequently foimd among the flavor volatiles of fruits and, like many naturally occurring chiral compounds, one enantiomer usually exists with a greater preponderance when compared with its antipode. Chiral odor compounds may show qualitative and quantitative differences in their odor properties (7). For example, (/ )-(+)-limonene has an orange-like aroma while (5)-(-)-limonene is turpentine-like (5)-(+)-carvone is characteristic of caraway while its enantiomer has a spearmint odor (2). However, other chiral compounds, such as y 6-lactones, show very little enantioselectivity of odor perception (7). The occurrence of chiral flavor compounds in enantiomeric excess provides the analyst with a means of authenticating natural flavorings, essential oils, and other plant extracts. The advent of cyclodextrin-based gas chromatography stationary phases has resulted in considerable activity in the analysis of chiral compounds in flavor extracts of fruits, spices and other plants (i-7). 

Jirovetz L, Buchbauer G, Stoyanova A et til (2004) Antimicrobieil testing and chiral phase gas chromatographic analysis of ddl oils and related key compounds. Nutrition 28 257-260 Jirovetz L, Buchbauer G, Bali S et al (2009) Antimicrobieil activities of essential ods of mint and peppermint as well as some of their mtiin compounds. J Essent Od Res 21 363-366 Kalemba D, Kunicka A (2003) Antibacterial and antifungeil properties of essential ods. Curr Med Chem 10 813-829... 

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