Comparative study of the phytochemical profile, antioxidant, and cytotoxicity activities of different co-product extracts of Cannabis sativa L. leaves

Cannabis sativa L. is one of the most extensively studied medicinal plants due to its wide array of bioactive metabolites with therapeutic and industrial applications. In this study, leaf co-products were valorized by assessing their phytochemical composition, antioxidant potential, and cytotoxic activity using three extraction techniques: decoction, sonication, and maceration. The decoction method produced the highest extraction yield, while sonication resulted in extracts with the greatest concentrations of total phenolics (43.2 mg GAE/g) and flavonoids (24.09 mg QE/g). Gas Chromatography–Mass Spectrometry (GC–MS) analysis revealed distinct chemical signatures for each extract, confirming the strong influence of the extraction process on metabolite recovery. Antioxidant evaluation showed that the sonication extract exhibited the most pronounced free radical scavenging effect (DPPH assay, IC₅₀ = 36.95 µg/mL), whereas the maceration extract exhibited the highest reducing power in the FRAP assay (97%). Cytotoxicity assays conducted on Vero (normal kidney) and HT-29 (human colorectal cancer) cell lines demonstrated inhibitory effects for all extracts, with the sonication extract showing the strongest activity against HT-29 cells. A significant association of the sonication extract between its antioxidant potential and cytotoxic properties was observed. Overall, these findings highlight Cannabis sativa leaf co-products as promising sources of bioactive compounds with potential applications in both pharmaceutical and nutraceutical development.