Bioactive Compounds and Antioxidant Activity in the Growing Tips of Date Palm Cultivars (Phoenix dactylifera L.)

Abstract

This study evaluated the total sugars, total phenolics, total flavonoids, and antioxidant activity (DPPH) in the growing tips of four date palm (Phoenix dactylifera L.) cultivars: Hillawi, Sayer, Zahdi, and Deiri. Significant differences were observed among cultivars for all traits. Sayer exhibited the highest total sugar content (0.73 mg/g DW), while Zahdi showed the lowest (0.37 mg/g DW). For total phenolics, Zahdi had the highest content (36 μg/g DW), and Hillawi the lowest (24 μg/g DW). Deiri showed the highest total flavonoid content (50 μg/g DW), whereas Hillawi had the lowest (26 μg/g DW). Regarding DPPH radical-scavenging activity, Zahdi recorded the highest activity (67.7%), Hillawi the lowest (52.8%), with Deiri and Sayer displaying intermediate values (63.2% and 58.4%, respectively). The results indicate a strong positive correlation between phenolic and flavonoid contents and antioxidant activity, confirming that these compounds are the major contributors to free radical scavenging in date palm growing tips. The observed variations reflect the genetic and biochemical differences among cultivars. These findings suggest that growing tips are a rich natural source of phenolic compounds with potent antioxidant properties and highlight the potential of selecting cultivars with higher antioxidant activity for nutritional and industrial applications