Comprehensive classification of USA cannabis samples based on chemical profiles of major cannabinoids and terpenoids, Ramia Z. Al Bakain et al., 2019

Comprehensive classification of USA cannabis samples based on chemical profiles of major cannabinoids and terpenoids

Ramia Z. Al Bakain, Yahya S. Al-Degs, James V. Cizdziel and Mahmoud A. Elsohly

Journal of Liquid Chromatography & Related Technologies, 2019

Doi : 10.1080/10826076.2019.1701015

 

ABSTRACT

Different USA-origin cannabis samples were analyzed by GC-FID to quantify all possible cannabinoids and terpenoids prior to their clustering. Chromatographic analysis confirmed the presence of seven cannabinoids and sixteen terpenoids with variable levels. Among tested cannabinoids, D9-Tetrahydro-cannabinol D9-THC and cannabinol CBN were available in excess amounts (1.2–8.0 wt%) and (0.22–1.1 wt%), respectively. Fenchol was the most abundant terpenoid with a range of (0.03–1.0 wt%). The measured chemical profile was used to cluster 23 USA states and to group plant samples using different unsupervised multivariate statistical tools. Clustering of plant samples and states was sensitive to the selected cannabinoids/terpenoids. Principal component analysis (PCA) indicated the importance of D9 THC, CBN, CBG, CBC, THCV, D8-THC, CBL, and fenchol for samples clustering. D9-THC was significant to separate California-origin samples while CBN and fenchol were dominant to separate Oregon-origin samples away from the rest of cannabis samples. A special PCA analysis was performed on cannabinoids after excluding D9-THC (due to its high variability in the same plant) and CBN (as a degradation by-product for THC). Results indicated that CBL and D8-THC were necessary to separate Nevada and Washington samples, while, CBC was necessary to isolate Oregon and Illinois plant samples. PCA based on terpenoids content confirmed the significance of caryophyllene, guaiol, limonene, linalool, and fenchol for clustering target. Fenchol played a major role for clustering plant samples that originated from Washington