## 4 Discussion  
This study was conducted to assess the proximate composition, phytochemical content, and antioxidant properties of Barhi, Ruthana, and Qatarah date seeds. Furthermore, the optimization of phenolic compounds and antioxidants' extraction by using different solvent systems was also performed. During the ripening stages of the date (Kimri, Khalal, Rutab, and Tamr), the moisture content decreased from 20% at the Kimri stage to about 6-12% at the Tamr stage [37]. The moisture contents analysis showed 12.4, 6.6, and 7.6% for Barhi, Ruthana, and Qatarah, respectively. Our findings agree with those reported for Emirati date seeds [38; 39], Moroccan date seeds [40], and Omani date seeds [10]. The variation in the moisture content among the cultivars might be due to the climate conditions and the relative humidity of the atmosphere. Nevertheless, the low moisture content of the seeds limits the growth of bacteria and allows for better preservation [41]. Carbohydrates are the main component of date seeds, and their quantity varies with different varieties [42]. The carbohydrate contents of the Barhi, Ruthana, and Qatarah date seeds were 70.0, 74.6, and 73.6%, respectively. These results agree with those found by [38], who analyzed six date cultivar pits (seeds), namely Mabroom, Lulu, Khalas, Fard, Khodari, and Abu Maan, and reported that the total carbohydrate content ranged from 70.14 to 78.70% but was lower than that of the Omani date seeds (83.14-86.89%), namely Shahal, Mabseeli, Um-Sellah [10], and Tunisian date seeds (Allig and Deglet Nour) (ranged between 81.0% and 83.1%) [43]. Interestingly, date seeds contain a significantly higher amount of protein and fat compared with date flesh [44; 45]. Date seeds were found to contain a significant amount of fat; it ranged from 6.3% for the Ruthana to 8.7% for the Barhi variety. This agrees with that of [44; 45], who reported the fat content of various Saudi date seeds, including Barhi, ranging from 7.83 to 8.69%. The date seed fat analysis revealed relatively high percentages of fatty acids, tocopbends, phenolic compounds, phytosterols, and carotenoids with excellent thermal and oxidative stability and a lower acidity content (0.5%) compared to soybean oil (0.86%), sunflower oil (1.4%), and palm Olean7 (4-5.5%), making it convenient for use in cosmetic and food applications [46]. The protein content of the date seeds did not significantly vary among the cultivars. The protein content of the seeds reported in this study were higher than those of the Tunisian date variety [47]. Date seed protein is reported to contain the most essential amino acids and has a higher concentration of sulfur amino acids than soybean, peanut, and cottonseed [48]. The differences in chemical composition could be due to the variability in the cultivars being studied, environmental conditions, agronomic practices, use of fertilizer, postharvest treatments, and storage conditions. Researchers from different regions have investigated date seeds' phytochemical compounds and their biological activities. Date seeds were reported to be a rich source of biologically active compounds such as phenolic compounds, tocopherols, carotenoids, and phytosterols that are responsible for several pharmacological activities, such as hypolipid-demic, antidiabetic, anti-inflammatory, anticancer, antioxidant, and antimicrobial activities [18; 49]. In this study, the Ruthana seed showed a significantly high TPC, followed by Barhi and Qatarah. The total phenolic content (TPC) ranges from 13.0 to 93.357 mg GAE/g. The 100% ethanol showed the highest phenolic content, while water had the lowest. This finding agrees with the results reported by [20; 50], who assessed the efficiency of different solvent systems and found that ethanol is the most effective solvent for extracting phenolic compounds from date seeds, whereas, other researchers [16; 18] observed that 50% and 70% acetone were more efficient in extracting phenolic compounds from date seeds.