Improvement of the antioxidant activity, phytochemicals, and cannabinoid compounds of Cannabis sativa by salicylic acid elicitor

Recently, due to the valuable and high level of phytochemical compounds such as cannabinoids and other secondary metabolites, the cultivation of Cannabis sativa has increased in the world. The current study was conducted to evaluate the potential role of exogenous salicylic acid (control, 0.01, 0.1, and 1 M) on enhanced production of pharmaceutically important phytochemicals. The sprayed aerial parts were evaluated based on phenolic (TPC) and flavonoids (TFC) contents, antioxidant capacity (by FRAP and DPPH assay), photosynthetic pigments including chlorophyll a, b (Chl a and Chl b), total carotenoids (TCC), and cannabinoid compounds. Quantification of aerial parts metabolites was performed using gas chromatography. The results indicated that phytochemical compounds and antioxidant capacity in C. sativa were influenced by various concentrations of salicylic acid (SA). The highest TPC, TFC, TCC, Chl a, Chl b, and antioxidant capacity were obtained in 1 M treatment, whereas the lowest of them were found in control plants. The major cannabinoids in the analyzed extracts were CBD (19.91%-37.81%), followed by Δ9-THC (10.04%-22.84%), and CBL (nd-14.78%). The highest CBD (37.81%) and Δ9-THC (22.84%) were obtained in 1 M of SA. These results suggest that the elicitor SA (especially 1 M) was able to improve antioxidant capacity, phytochemicals, and cannabinoid compounds.