Comparative Biochemical Profiling of Three Commercial Date Palm Cultivars (Sukkary, Mejhoul, and Khlass) During Fruit Development.

Date palm (Phoenix dactylifera L.) plays a vital agronomic and nutritional role in arid regions of the Gulf Cooperation Council (GCC), where sustainable crop improvement is essential. Among the many cultivars, Sukkary, Mejhoul, and Khlass stand out for their commercial importance, adaptability, and distinctive fruit characteristics. This study investigated their metabolomic profiles during fruit development, focusing on sugars, amino acids, polyphenols, and organic acids. Distinct biochemical signatures were identified among cultivars. Mejhoul exhibited the highest Brix (~79), reflecting elevated glucose and fructose, while Sukkary and Khlass (~72) showed sucrose predominance. Sugar profiles revealed cultivar-specific patterns: Sukkary accumulated more sucrose, whereas Mejhoul and Khlass had higher invert sugars, with inositol uniquely abundant in Khlass. Amino acid analysis showed Sukkary enriched in glutamine, valine, and GABA-metabolites linked to nitrogen metabolism and stress tolerance. Mejhoul contained more tyrosine and glutamine, and Khlass was rich in methionine and urea. Organic acid profiling highlighted Sukkary's dominance in TCA intermediates (fumaric, succinic, and malic acids), Khlass in citric and citraconic acids, and lower organic acid levels in Mejhoul. Sukkary also exhibited the highest polyphenol content, consistent with elevated phenylalanine and activation of the phenylpropanoid pathway. These metabolomic distinctions reflect cultivar-specific physiological and nutritional traits: Mejhoul suits fresh consumption and fermentation, Sukkary favors functional food and storage potential, and Khlass offers balanced sugar-acid and inositol profiles. The findings provide a biochemical basis for cultivar-specific breeding, postharvest optimization, and enhanced nutritional value under climate stress.