- Myristic Acid
- Palmitic Acid
- Oleic Acid
- Stearic Acid
Samples were analyzed by gas chromatography/mass spectrometry to determine delta-9-tetrahydrocannabinol, other minor cannabinoid congeners, and fatty acids. Although cannabis seeds and the oil derived from those seeds are known to be rich in fatty acids, this is believed to be the first study demonstrating the presence of fatty acids in marijuana. The potential value of the results in source determination and comparative analyses is discussed.
Materials and Methods: All chemical and reagents employed were of analytical grade. Fatty acid standards were purchased from Sigma-Aldrich. A mixture of the standards, each at a concentration of 0.1 mg/mL, was used for method development. Twenty marijuana samples from the illicit Roman market were analyzed. The samples were stored in the dark in a dry-box prior to analysis. Individual samples (100 milligrams) were extracted with 0.5 mL of chloroform solution at room temperature, and an aliquot injected into the GC/MS.
Results and Discussion
Cannabis seeds and seed oils have been shown to contain up to 20 fatty acids. Analysis of the 20 marijuana samples selected for this study confirmed the (varying) presence of myristic, palmitic, oleic, and/or stearic acids.
The acids varied dramatically by sample. All four acids were present in only 10 of the 20 samples (1,2,4,5,10,11,13,15,16, and 17). Three acids (myristic, palmitic, and stearic) were present in samples 3 and 18; two acids (myristic and palmitic) were present in samples 6,7,12, and 19; only one acid (oleic) was present in samples 9,14 and 20; and finally, no fatty acids were detected in sample 8. The geographic origin for samples 6 and 7 was alleged to be the Netherlands, and in fact those samples had similar delta-9-tetrahydrocannabinol contents (about 1%) and similar impurity profiles, and were also similar in their fatty acid profile (but with only two acids present and with actual origin unknown, the results are interesting but of only curiosity value). Nonetheless, these results suggest that the fatty acid profile of marijuana may be useful for comparative analyses (sample - sample comparisons). The analysis is easy, quick, and sufficiently sensitive for small sample amounts. Although unlikely, the method may also be useful for source determination; however, such an advance would require a much larger database of authentics (samples of known origin).
Additional research is planned for more sensitive determination of fatty acids in marijuana by derivatizing the acids prior to analysis. The results will be the subject of a future report.
Fun huh? :amazed: The attached image presents the results by sample (ratio’d against the combined cannabidiol (CBD) and cannabinol (CBN) content).
M = Myristic Acid
P = Palmitic Acid
O = Oleic Acid
S = Stearic Acid
CBD = Cannabidiol
CBN = Cannabinol
N = None Detected
I wish they had images of the 20 samples! Just goes to show you that you never know what your weed's got in it. The high can truly vary based on the fatty acid content and respective ratios.