Towards the Utilization of Date Palm (<i>Phoenix dactylifera</i>) Leaves as a Rich Source of Antioxidants

Abstract

Three varieties of date palm (Phoenix dactylifera) leaves (DPL) namely: Sagaie, Khalas, and Nabtat Alsaif were examined for their antioxidant activities. DPL extracts showed a total phenolic content ranged between 1498.14 ± 100.52 - 4374.76 ± 657.64 mg gallic acid equivalent (GAE)/100g dry weight (DW) and a total flavonoid ranged between 134.70 ± 16.24 - 224.62 ± 22.35 mg quercetin (QE)/100g (DW). The IC50s for scavenging ABTS radical were ranged between 71.87 ± 14.37- 217.87 ± 27.40µg Trolox equivalent, whereas that required for scavenging DPPH were ranged between 197.86 ± 17.60-693.32 ± 25.44 µg ascorbic acid equivalent. DPL extracts potentially scavenged hydroxyl and superoxide anion radicals, IC50s values were ranged between 208.04 ± 12.76-719.63 ± 24.38 and 825.92 ± 19.40 -1193.20 ± 28.74µg GAE respectively. DPL extracts showed a good activity against ferric reducing antioxidant power (FRAP) ranged between 7.69 ± 0.47- 22.13 ± 1.36 mmol ascorbic acid equivalent/100g. DPL extracts showed a considerable antioxidant activity, therefore, DPL could be effectively used as natural source of antioxidant in food and pharmaceutical industries.