Chirality evaluation

K. Rettinger, V. Karl, H.-G. Schmarx, E. Dettmar, U. Hener and A. Mosandl, Chirospeciflc analysis of 2-alkyl-branched alcohols, acids and esters chirality evaluation of 2-methylbutanoates from apples and pineapples , Phytochem. Anal. 2 184-188 (1991). 

P Kreis and A. Mosandl, Chfral compounds of essential oils. Part XIII. Simultaneous chirality evaluation of geranium oil constituents , Flav. Fragr. 7. 8 161 -168 (1992). 

A. Mosandl, C. Askari, U. Hener, D. Juchelka, D. Eehmann, P Kreis, C. Motz, U. Palm and H.-G. Schmarx, Chirality evaluation in flavour and essential oil analysis , Chirality 4 50-55 (1992). 

Ekgorg-Ott, K.H., Armstrong, D.W. (1996). Chirality evaluation of the concentration and enantiomeric purity of selected free amino acids in fermented malt beverages (beers). Chirality 8, 49-57. 

Bernreuther A, Schreier P, Multidimensional gas chromatography-mass spectrometry A powerful tool for the direct chiral evaluation of aroma compounds in plant tissues, II, Linalool in essential oils and fruits PhytochemAnall. G7— 7(), 1991. 

Mosandl A, Schubert V, Stereoisomeric flavor compounds XXXVII Enantiomer separation of l-alken-3-yl esters and their chirality evaluation from essential oils using multidimensional gas chromatography (MDGC),/ Essen Oil Res 2 121— 132, 1990. 

Ferreira V, Jarauta I, Ortega L, Cacho J (2004) Simple strategy for the optimization of solid-phase extraction procedures through the use of solid-liquid distribution coefficients—application to the determination of aliphatic lactones in wine. J Chromatogr A 1025 147 Rettinger K, Karl V, Schmarr HG, Dettmar F, Hener U, Mosandl A (1991) Chirospecific analysis of 2-alkylbranched alcohols, -acids, and -esters chirality evaluation of 2-methylbutanoates from apples and pineapples. Phytochem Anal 2 184... 

D. Jukelka, A. Steil, K. Witt and A. Mosandl, Chiral compounds of essential oils. XX. Chirality evaluation and authenticity profiles of neroli and petitgrain oils , 7. Essential Oil Res. 8 487-497(1996). 

B. Weckerle, R. Bastl-Borrmann, E. Richling, K. Hor, C. Ruff, P. Schreier (2001). Cactus pear (Opuntia ficus indica) flavour constituents - chiral evaluation (MDGC-MS) and isotope ratio (HRGC-IRMS) analysis. Flav. Fragr. 1.16. 360-363... 

Consequently, high efficiency sample clean-up remains an essential condition to chirality evaluation and legally binding interpretation of authenticity assessment of flavourings [53]. 

With regard to chirality evaluation as an indicator for the genuineness of natural flavourings and fragrances only chiral volatiles of high enantiomeric purity and characteristic and small ranges of ee-values should be validated in relation to their total amounts (Table 4). Furthermore, it is remarkable to pay more attention to the odour activity values (OAV) of compounds analyzed [77, 78]. 

Chirality evaluation of linalyl acetate and linalool have been introduced as new and substantial criteria in the authenticity control of lavender oils. In particular, linalyl acetate from genuine lavender oils has high enantiomeric purity favouring the R-configuration, irrespective of the Lavandula species, and storage or work-up conditions [32]. Using 2,3-di-0-acylated-6-0-silylated cyclodextrins as a new generation of chiral stationary phases in enantio-cGC, most of chiral compounds of Lavandula oil, are stereoanalyzed simultaneously (Fig. 6.37 Fig. 6.38). 

Nevertheless, under the conditions of good manufacturing practice (GMP) the chirality evaluation of linalool has proved to be a reliable indicator in the authenticity control of lavender, bergamot, and orange oils. This fact will be of considerable importance in the quality assurance for the flavour and fragrance industry. 

If to extend these experiences to the chirality evaluation of linalool from other natural substrates, generally attention must be paid to the GMP-condi-tions as well as to the pH-values of the substrates investigated. 

Comparative investigations on the enantiomeric purity of linalool and linalyl acetate in the essential oils of Lavandula angustrfolia MILLER leads to quick and simple techniques of gas chromatographic chirality evaluation of lavender oil compounds. Their usefulness in the authenticity control of lavender oil compounds is demonstrated in Lig. 6.39 [95]. 

G. Singer, G. Heusinger, O. Frbhlich, P. Schreier and A. Mosandl. Chirality evaluation of 2-methyl-4-propyl-l,3-oxathiane from the yellow passion fruit. J. Agric. Food Chem., 34, 1029-1033 (1986). 

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... 

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