Abstract:

Two flavonoids were isolated and purified from the extract of Exocarpium Citri grandis by high performance
countercurrent chromatography (HPCCC). A two-phase solvent systems composed of ethyl acetate-1-butanol-water (1:4:5,
V/V) was used to separate naringin directly from the crude extract of Exocarpium Citri grandis. The method allowed the
separation of 83.3 mg of individual naringin with purity of over 98% from 1 g of crude extract. A solvent system composed
of dichloromethane, methanol and water (10:7:4, V/V), or hexane, ethyl acetate, methanol and water (1:1:1:1, V/V) was used
in two steps to separate naringenin from the acid hydrolyzed product of crude extract. The method allowed the separation
of 27.5 mg of individual naringenin with purity of over 98% from 1 g of acid hydrolyzed product. Separation of the two
compounds was achieved within 60 min. The HPCCC method is a relatively simple and fast method with a high-loading
capacity suitable for the isolation and purification of flavonoids from Exocarpium Citri grandis.

Key words: high-performance counter-current chromatography (HPCCC), Exocarpium Citri grandis, naringin, naringenin