Phenols and Flavonoids as an Indicator for Selecting the most Suitable Solvent for Resveratrol Flavonoid Extraction

Abstract

Abstract Grape juice residues were purchased from a shop selling grape guice in Baghdad then washed with tap water and dried in oven(40-50) °C some samples were milling during the experiment and others were left without milling, ethanol, methanol with concentration 70, 80, 90%, boiled distilled water and ethyl acetate were used by maceration the boiling water extract (BWE) was characterized by the highest concentration of phenols then methanol extract (ME90%) and ethanol extract (EE80%) 41.70, 40.50 and 23.27 mg/gm respectively for the milled samples while methanol 70% was the most solvent for the unground samples then ethanol 80% and methanol 90% with phenols 33.08, 27.17 and 23.84 mg/gm respectively also the BWE was superior to the ground samples and ME 70% for the unground 0.12 and 0.13 respectively the concentration of phenols55.47mg/gm increased to and flavonoids to 0.55mg/gm with assist extraction microwave in ground samples the resveratrol crystals appeared rhomboid and irregular with peal brown color the retention time 4.90 min and for standard 4.89 min.