[01] Hayette Louaileche, Laboratory of Applied Biochemistry, Faculty of Life and Natural sciences, University of Bejaia, Bejaia, Algeria. [02] Djillali Hammiche, Laboratory of Applied Biochemistry, Faculty of Life and Natural sciences, University of Bejaia, Bejaia, Algeria. [03] Fares Hamoudi, Laboratory of Applied Biochemistry, Faculty of Life and Natural sciences, University of Bejaia, Bejaia, Algeria.

The objective of this study was to determine the content of bioactive substances (total phenolic compounds and flavonoids) and the antioxidant activity of aqueous extracts of date varieties grown in Algeria (Ourrous, Deglet Nour, Beid Lahmam, Outkbala, Taneslit, Tamjouherte, Tazerzeite and Takermoust) using spectrophotometric methods. Phenolic compounds were determined by the Folin-Ciocalteu reagent. The total phenolic content ranged from 169.18 to 381.76 mg of gallic acid equivalents per 100 g dry matter, while the flavonoid content varied between 28.68 and 95.22 mg quercetin equivalents per 100 g dry matter. The antioxidant capacity was determined in vitro using scavenging effect of diphenylpicryl-hydrazyl radical (DPPH) and phosphomolybdenum assay. The results indicated that cultivar had pronounced effects on both phenolic compound levels and antioxidant potential. Among the studied samples, Ourrous variety contained the highest amounts of bioactive compounds and exhibited the best antioxidant activity. The evaluation of antioxidant activity of the eight date varieties revealed highly significant correlation (p<0.001) between anti-radical ability and total phenolic (r = 0.77), and flavonoid contents (r = 0.88).

Phoenix Dactylifera, Varieties, Phenolic Content, Antioxidant Activity

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