Purification of the proanthocyanidins from Lycium ruthenicum Murr. by macroporous resin

Macroporous resin were used to purify the crude proanthocynidins extract from Lycium ruthenicum Murr..Absorbation and desorption capacity were determined to study the purification effect on proanthpcyanidins of AB-8, D130, D101, HPD100, D101-1 and polyamide macroporous resin, then desorption capacity was used to evaluate the effect of eluant concentration and elution velocity for purifying.The results showed that D101 was better for purification among the supplied macroporous resins.After static absorbation, proanthocynidins was eluated by alcohol of 95% at the elution velocity of 2.5 BV/h and eluation volume of 4.0 BV, and the purity of proanthocynidins was enhanced from 31.33% to 68.03% by macroporous resin absorbation.After that, ethyl acetate was used to extract the oligomeric proanthocyanidins, and the DP was reduced from 8.98 to 3.17.Catechin, epicatechin and proanthocyanidin B2 were all detected in oligomeric proanthocyanidins by HPLC method, and their total content was 18.73% according to their peak area proportion.