Application of chiral GC-MS analysis in the
detection of natural products adulteration - The
example of Chios mastic gum essential oil
Paraschos S, Magiatis P, Skaltsounis AL
Laboratory of Pharmacognosy and Natural Products
Chemistry, Faculty of Pharmacy, University of Athens,
Panepistimiopolis Zografou, GR 15771, Athens, Greece
The enantiomeric ratio of volatile compounds is characteristic in each essential oil, but it cannot be determined by usual capillary GCMS ana-lysis. The essential oil of Pistacia lentiscus var. chia L. (Anacardiaceae), mastic oil, is a valuable product. The case of dietary and cosmetic pro-ducts containing mastic oil is of great importance, due to the well-es-tablished biological activities of mastic and mastic oil [1,2], the signify-cance of mastic gum for greek economy and the increasing international interest for such products. Numerous commercial items with a claim of mastic oil content but without certification are found in the market. In order to detect possible adulteration of this type, a method based on the separation of chiral constituents and the determination of their ratio by chiral GCMS analysis has been developed. Samples of cosmetic products (shampoos, showers gels, hand and body creams, toothpastes, soaps) and dietary products (chewing gums) from different companies were extracted with n-hexane for the retrieval of the volatile compounds and the extracts were analyzed by chiral GCMS. The results were com-pared with those of the analysis of 30 original mastic oil samples sup-plied by the Chios Mastic Gum Growers Association, as well as comer-cial mastic oils marketed by other companies. The main discriminating factor was found to be the (+)/(-) a-pinene ratio, which should be less than 99:1, as determined by original mastic oil analysis. Several com-mercial samples were found to contain much higher proportions of (-) a-pinene, an indication that commercial racemic a-pinene was used for the adulteration of the product. The use of this method to determine such type of adulterations can be helpful in establishing quality and originality in natural product commercial use. Acknowledgement: Chios Mastic Gum Growers Association. References: 1.Magiatis,P. et al (1999) Planta Med 65:749-751. 2.Paraschos, S. et al (2007) Antimicrob. Agents Chemother. 51:551-559.
This paper is part of the 03ED375 research project, implemented within the framework of the -Reinforcement Programme of Human Research Manpower - (PENED) and co-financed by National and Community Funds (25% from the Greek Ministry of Development-General Secretariat of Research and Technology and 75% from E.U.-European Social Fund).