Isolation and purification of flavones from Murraya exotica L. by high-speed counter-current chromatography

Abstract

High-speed counter-current chromatography HSCCC was used to isolate and pu rify flavones from Murraya exotica L. The optimum separation conditions were as follows: A two-phase solvent system was petroleum ether-ethyl acetate-methanol-water(5:5:4.8:5,v/v/v/v). The lower phase as the mobile phase was operated at a flow rate of 2.0 mL/min , while the apparatus rotated at 800 r/min . Each time 200 mg of the sample was loaded. Under these conditions ,54.31 mg o f recrystallized 5,7,3' , 4', 5' -pentamethoxyflavone,107.68 mg of 5-hydroxy -6,7,3',4'-tetramethoxyflavone,215.54 mg of 5-hydroxy -6,7,8,3',4'-pentamethoxyflavone,and 84.36 mg of 5-hydroxy-6,7 ,8 ,3 ' ,4 ',5 '-hexamethoxyflavone with their purities over 95% were successfully obtained from 4.0g of the crude extract of Murraya exotica L. The four compounds were analyzed by high performance liquid chromatography (HPLC) ,and identified by mass spectrometry (MS) ,1H-nuclear magnetic resonance (NMR) and 13C-NMR. The compound 5 -hydro xy-6,7 ,',4 ' -tetramethoxyflavone was fo r the firs t time isolated and p urified from Murraya exotica L.