Cannabis trichomes are known as the main site of cannabinoids production, the responsible
compounds for most biological activities of the plant. This study reports 1H NMR based-metabolomics and cannabinoids analysis of trichomes of 4 medicinal Cannabis varieties, Bediol, Bedica, Bedrobinol, and Bedrocan, in order to investigate cannabinoids
production and metabolites profiles of the trichomes during the last 4 weeks of flowering
period. Analysis of 1H NMR spectra revealed totally 6 identified cannabinoids in the chloroform extracts,
THCA (1), CBDA (2), CBCA (3), CBGA (4), THC (5) and CBD (6), and 20 compounds in the
water extracts including sugars, amino acids, and other acidic compounds. Quantification
analysis using 1H NMR method showed that production of total cannabinoids of Bedrocan and Bedica trichomes
increased from week 5 (Bedrocan: 63.01 mg/g) till week 7 (Bedrocan: 111.04 mg/g) and
then decreased at week 8 (Bedrocan: 79.76 mg/g). Meanwhile cannabinoids production
of Bedrobinol and Bediol trichomes increased during the monitoring time. Different
metabolites profiles within trichomes varieties were revealed by PLSDA models of metabolomics.
Important differential metabolites in this discrimination were THCA (1) and CBDA (2)
on the chloroform extracts, and were asparagine, choline, fructose and glucose on
the water extracts. Furthermore PLSDA classified the trichomes of every variety based
on their harvested weeks. THCA (1) was found as an important discriminant compound
in the chloroform extracts of every variety. Meanwhile, threonine, asparagine and
fructose were detected as differential metabolites in the water extracts of every
variety. This study indicated that Cannabis tricomes during flowering period produced metabolites, particularly cannabinoids in
different amounts depending on the time and the plant variety. Furthermore it is the
first report for monitoring metabolites production in plant trichomes using 1H NMR-based metabolomics.