Phytochemical Profile and Functional Properties of the Husk of Argania spinosa (L.) Skeel

Due to the limited scientific exploration of Argania spinosa (L.) skeel husk, this study presents the first investigation of the metabolite profile of methanol and acetone extracts analyzed by liquid chromatography coupled with electrospray ionization and high-resolution multistage mass spectrometry (LC-ESI/HRMSMS). A total of 43 compounds, including hydroxycinnamic acid and flavonoid derivatives, saponins, and triterpenic acids, were identified, some of which have not been previously reported in this species. The total phenols (TPC) and flavonoids (TFC) content were spectrophotometrically determined. A multi-target approach was applied to investigate the antioxidant potential using 1,1-Diphenyl-2-picrylhydrazyl (DPPH), 2,2-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid (ABTS), β-carotene bleaching, and Ferric Reducing Ability Power (FRAP) tests. Carbohydrate hydrolyzing enzymes and lipase inhibitory activities were also assessed. The acetone extract exhibited the highest TPC and TFC values, resulting in being the most active in β-carotene bleaching test with IC50 values of 26.68 and 13.82 µg/mL, after 30 and 60 min of incubation, respectively. Moreover, it was the most active against both α-glucosidase and α-amylase enzymes with IC50 values of 12.37 and 18.93 µg/mL, respectively. These results pointed out that this by-product is a rich source of bioactive phytochemicals potentially useful for prevention of type 2 diabetes and obesity.