Abstract: Purification of lignans and pinoresinol diglucoside(PDG) from Eucommia bark extract was studied by a combined method of macroporous adsorption resin-C₁₈ column chromatography and silica gel column chromatography. The results indicated that AB-8 resin was the best one on the adsorption and desorption rates by comparing with the other 3 kinds of resins. The purity of effective part of lignans and the crude product of PDG were respectively from 23.33% to 71.61% and 0.960 5% to 8.070% through AB-8 resin once. Then the purity of PDG increased to 53.12% after C₁₈ purification and finally reached 91.50% after purifying by normal phase silica gel column chromatography.

Key words: Eucommia ulmoides Oliv., lignans, pinoresinol diglucoside, purification technology