Aqueous and alcoholic extractions were performed on Khastawi date seed powder to isolate flavonoids and estimate the total phenolic content. The extracted phenolic compounds were subsequently evaluated for their antibiotic activity and reducing strength. Phenolic compounds were detected using the FTIR and UV-Vis techniques. Alcoholic extraction proved superior, as flavonoids-being phenolic compounds exhibit greater solubility in alcohol than in water. The yield of the alcoholic extract was found to be 57%. The FTIR spectrum displayed a strong absorption band at 3200-3600 cm⁻¹ (O-H stretching), which was accompanied by other peaks at 2850–3100 cm⁻¹ (C–H stretching) and >3000 cm⁻¹ (aromatic C–H). C=C stretching (1400-1600 cm⁻¹) and phenolic C-O stretching (1150-1250 cm⁻¹) further supported flavonoid presence. UV-Vis spectra showed clearly defined peaks that are characteristic of high concentration and conjugation of phenolic compounds. According to High-Performance Liquid Chromatography (HPLC) analysis, flavonoids extraction through alcohol was found to be more yielding, since the area under the curve was larger. EDX analysis pointed to strong signals from iron (Fe) and oxygen, which could be interpreted as indications of high flavonoid content and great reducing ability. The analyzed material displayed peaks at 136.2 and 847.3cps. The antibiotic activity of Khastawi date seeds extracts (for ethanol and ethyl acetate) at a concentration of 50 mg/ml showed inhibitory effect against both of G+ (Staphylococcus aureus and Staphylococcus epidermidis) and G- (Acinetobacter, Proteus) bacteria. G+ strains showed slightly higher sensitivity, with inhibition zones ranging from 10-13 mm. Generally, the ethanol extract exhibited slightly higher antibacterial activity compared to the ethyl acetate extract.
A. H. AlMoula (Wed,) studied this question.