Résumé:
Plants have always been an important source of medicine. Most people in the world, only use traditional herbal remedies to treat themselves, Among these plants, Cordyceps militaris is one of the important medical fungi in Asian countries, because of its various beneficial effects on human health. The objective of this work is the phytochemical analysis and evaluation of the in vitro antioxidant activity of an aqueous xtra of Cordyceps militaris plants. The total polyphenols content was determined by the FolinCiocalteuen method using gallic acid as a standard. While, flavonoids have been quantified by the method of aluminum trichloride of which quercetin is used as standard. The results revealed the richness of Cordyceps militaris extract in phenolic compounds and flavonoids with contents of (747,35±5,91)mg EAG/g and (441,18±1,38)mg EQ/grespectively. The evaluation of antioxidant activity by the oxidation test of the radical 2,2- diphenyl-1-picrylhydrazyl (DPPH), ABTS (2,2- azinobis- [3- ethylbenzothiazoline-6- sulfonicacid]), and the ferric iron test (FRAP) using ascorbic acid and Trolox as successive synthetic references. The results of these studies showed that Cordyceps militaris extract is given a good reducing activity with IC50DPPH(0,27±14,76)mg/ml; IC50ABTS(0,25±15,62)mg/ml; IC50FRAP(0,08±0,33)mg/ml. On the other hand, the correlation between the antioxidant activity tests DPPH, ABTS and FRAP showed a strong correlation. In addition, a good correlation was revealed between total phenol levels and flavonoids and antioxidant activity.