Propriétés antioxydantes d’extraits phénoliques de coeur d’artichaut

Abstract

The artichoke (Cynara scolymus L.), plant of the Asteraceae family is an edible vegetable from the Mediterranean region widely distributed in Algeria, and a good source of natural antioxidants for its richness inpolyphenols. Due to the increasing incidence of many diseases linked to oxidative stress, The present study concerns the determination of the overall chemical composition, the extraction of polyphenols, the estimation of their total dosage by the Folin-Ciocalteu method, of flavonoids by the AlCl3 method and tannins by the vanillin method to be able to make a qualitative and quantitative assessment and the evaluation of antioxidant properties in vitro by three different techniques namely iron reduction (FRAP), free radical scavenging ( DPPH) and total antioxidant capacity (TAC) of the artichoke heart extract. Studies by researchers show that the artichoke heart contains 29.61% crude fiber, 9.31% ash and 87.06% water, rich in total sugars (42.7%), contains protein (17.85%) and lipid (1.56%), richness in phenolic compounds (50.04 mg GAE / g), flavonoids (9.85 mg / g), tannins (1, 74 mg eq / g) and the presence of saponins and alkaloids. Thus, antioxidant activity tests have antioxidant properties: a reduction in iron (343 umol / g), a strong capacity for trapping DPPH radicals (67.83%), a total antioxidant capacity (916.63 ppm). The high antioxidant capacity of artichoke hearts gives it the power to be an excellent source of secondary metabolites that are capable of inhibiting the activity of free radicals.