Abstract:Macroporous adsorption resins were used to purify the crude proanthocynidins extract from red raspberry seeds, and then the polyamide was used for secondary purification of the oligomeric procyanidins. The results showed that the macroporous resin adsorbing the crude extract of proanthocyanidin from red raspberry seed was eluted with 40% ethanol to obtain oligomeric procyanidins, which were then eluted with 60% ethanol to obtain high polymeric proanthocyanidins. The optimum parameters for polyamide were determined as follows: sample concentration 2 mg/mL, flow rate 1.5 mL/min, sample volume 100 mL; 70% ethanol as the eluent, flow rate 1.5 mL/min, eluent volume 150 mL, the purity of oligomeric proanthocyanidins increased from 52.36% to 71.09%. Simulated gastric digestion 0-2.5 h and intestinal digestion 0-3.0 h, The release of oligomeric proanthocyanidins and high polymeric proanthocyanidins gradually increased to 14.23, 5.02 mg/g and 27.79, 12.62 mg/g, which indicated that pepsin, pancreatin and bile promoted the release of oligomeric proanthocyanidins and high polymeric proanthocyanidins from red raspberry seeds during simulated gastrointestinal digestion. The release of oligomeric procyanidins was much higher than that of high polymeric proanthocyanidins, indicating that oligomeric procyanidins were more beneficial to human body absorption and utilization.