Authentication of Commercial Geranium Oil and Geranium Based Dietary Supplements and Workout Products
A series of four marker (target) compounds that are common to most geranium extracts and oils was determined. The functionally distinctive markers selected were a ketone (isomenthone), two alcohols (citronellol and geraniol) as well as an ester (citronellyl formate). An analytical method involving GC/MS in the selected ion monitor mode was developed and validated for the quantitative detection of the four marker compounds common to all geranium products. Moreover, the validated analytical method was applied to investigate a series of steam-distilled geranium oils, the n-hexane extracts of the leaf and stem portions of an authenticated Pelargonium graveolens plant, and three commercial pre-workout products containing DMAA (1,3-dimethylamylamine) supposedly derived from the stem portion of Pelargonium graveolens. All four markers were found present in the geranium oils and extracts. On the other hand, none of the three commercial products purportedly derived from geranium stems contained any of the four geranium marker compounds at a concentration greater than the limit of detection (0.05 – 0.5 µg/mL) of the analytical method.
Acknowledgements: This research was supported by Food and Drug Administration grant number 5U01FD004246 and the United States Department of Agriculture, Agricultural Research Service, Specific Cooperative Agreement No. 58 – 6408 – 02 – 1-612. The GC/MS instrumentation for this research was graciously supplied by Agilent Technologies.