Preparative Separation of Flavones from Peanut Hull by High-Speed Counter-Current Chromatography

Three flavones were prepared,isolated and purified from peanut hull by high-speed counter-current chromatography (HSCCC) for the first time.A two-phase solvent system composed of n-hexane:ethyl acetate:methanol:water:acetic acid (5:3:3.5:5:0.25,v/v) was used.The obtained fractions were analyzed by HPLC and identified by MS,1H and 13C NMR.Within 100 minute,11.0 mg of luteolin,2.2 mg of diosmetin,and 5.2 mg of 5,7-dihydroxychromone with their purities over 96.0% were obtained from 70 mg crude extract of peanut hull in one-step elution under the conditions of a flow rate of 2.0 mL/min,while the apparatus rotated at 800 r/min and the effluent was detected at 275 nm.The results indicated that HSCCC was a powerful technique for the separation and purification of flavones from the peanut hull.