Identification of phenolic compounds from inflorescences of non-psychoactive Cannabis sativa L. by UHPLC-HRMS and in vitro assessment of the antiproliferative activity against colorectal cancer

Phenolic compounds from Cannabis sativa L. (Cannabaceae family), in particular cannflavins, are known to possess several biological properties. However, their antiproliferative activity, being of great interest from a medicinal chemistry point of view, has not been deeply investigated so far in the literature. In the light of this, the aim of this study was to obtain an enriched fraction of polyphenols (namely PEF) from inflorescences of a non-psychoactive C. sativa (hemp) variety and to evaluate its antiproliferative activity against cancer cells, capitalizing on a new and selective extraction method for hemp polyphenols, followed by preparative flash column chromatography. Untargeted metabolomics, using a new method based on ultra-high-performance liquid chromatography coupled with high-resolution mass spectrometry (UHPLC-HRMS), was applied here for the first time to fully characterize PEF. Then, the main phenolic compounds were quantified by HPLC-UV. The antiproliferative activity of PEF and of the isolated compounds was assessed in vitro for the first time against Caco-2 and SW480 human colon adenocarcinoma cell lines providing promising IC₅₀ values, in comparison with the reference drug used in therapy for this cancer type. Based on these results, PEF can be considered as a new highly potential therapeutic product to be further investigated against colorectal cancer, thanks to the possible synergistic interaction of its compounds.