Chemical Constituents of Date Palm (Phoenix dactylifera L.) Fruit-Free Bunches and Their Biological Activities

Phytochemical investigation of Phoenix dactylifera L. (date palm) fruit-free bunches lead to the isolation of seven compounds, including new trisaccharide (β-D-glucopyranosyl-(1→2)-β-D-fructofuranosyl-(6→6)-α- D-glucopyranoside), two flavonoid glycosides (isorhametin-3-O-β-D-glucoside and neodiosmin), three sugars (maltotriose, maltose and sucrose) and β-sitosterol-3-O-β-D-glucoside. The structures were elucidated using detailed analysis of one- and two-dimensional nuclear magnetic resonance spectra and mass spectrometric data along with comparison to published data. Computational and pharmacological investigations were performed. First, molecular docking studies were used to explore interaction of the new trisaccharide and its derivatives as well as the isolated flavonoid glycosides with human leukotriene A4 hydrolase (LTA4H) in the search for clinically active LTA4 H inhibitors. Second, study of the butanol fraction of the palm fruit-free bunch and the new trisaccharide showed their significant antimicrobial activity against Candida albicans and moderate activity against Bacillus subtilis. Finally, measuring the in-vitro prothrombin time (PT) and activated partial thromboplastin time (APTT) showed a promising anticoagulant activity of the total ethanolic extract, butanol fraction and the new trisaccharide.