The Antioxidant and Neuroprotective Potential of Leaves and Inflorescences Extracts of Selected Hemp Varieties Obtained with scCO2.

Cannabis sativa, a versatile plant with numerous varieties, holds promising potential for a wide range of biological activity. As raw materials for research, we chose leaves and inflorescences of hemp varieties such as Białobrzeskie, Henola, and Tygra, which are cultivated mainly for their fibers or seeds. The choice of extraction is a key step in obtaining the selected compositions of active compounds from plant material. Bearing in mind the lipophilic nature of cannabinoids, we performed supercritical carbon dioxide (scCO2) extraction at 50 °C under 2000 (a) and 6000 PSI (b). The cannabinoid contents were determined with the use of the HPLC-DAD method. The antioxidant capabilities were assessed through a series of procedures, including the DPPH, ABTS, CUPRAC, and FRAP methods. The capacity to inhibit enzymes that play a role in the progression of neurodegenerative diseases, such as acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and tyrosinase was also studied. The dominant cannabinoids in the extracts were cannabidiol (CBD) and cannabidiolic acid (CBDA). The highest concentration of eight cannabinoids was detected in the Tygra inflorescences extract (b). The most notable antioxidant properties were provided by the Tygra inflorescences extract (b). Nonetheless, it was the Henola inflorescences extract (b) that demonstrated the most efficient inhibition of AChE and BChE, and tyrosinase was inhibited the most significantly by the Białobrzeskie inflorescences extract (b). Multidimensional comparative analysis enrolled all assays and revealed that the Henola inflorescences extract (b) showed the most substantial neuroprotective potential.