Total phenolic content and antioxidant activity of date palm (Phoenix dactylifera L.) seed extracts using soxhlet method

The date palm (Phoenix dactylifera L.) is one of the oldest fruit crops grown in the arid regions of the Arabian Peninsula, North Africa, and the Middle East. It has numerous uses in medicine, pharmacognosy, and even religion, making it more than just a valuable food source. The aim of the study is to assess the yield percentage, total phenolic content (TPC), phenolic compositions, and antioxidant activity of three P. dactylifera cultivars, namely, Khudori, Sabaka, and Nabtat Ali, using methanol and hexane as solvents for Soxhlet extraction. The antioxidant potential of the extract was evaluated based on total phenolic content, the 2,2, diphenyl-2-picryl-hydroxyl (DPPH) assay, and the ferric-reducing antioxidant power (FRAP) assay, whereas phenolic compounds were identified and quantified using HPLC. Methanolic extracts of various seed cultivars showed higher yield recovery and TPC than hexane extracts. Khudori seeds demonstrated the highest antioxidant capacities compared to the other cultivars, with 124.54 ± 2.89 mg GAE /100 g for TPC, 79.67 ± 4.53 percentage inhibition for DPPH, and 1.49 ± 0.53 mMTE/100g for FRAP. It shows the potential of the Khudori seed extracts as a good source of antioxidant nutraceutical food and useful drug development that can help with free radical-related diseases.