Extraction and Purification of Resveratrol from Herbal Residues of Polygonum cuspidatum Sieb. et Zucc

The determination,extraction and purification of resveratrol from herbal residues of Polygonum cuspidatum Sieb.et Zucc.were investigated.The extraction process was optimized by orthogonal design with the content of resveratrol as index.The resveratrol in extract was separated by macroporous adsorptive resin and chromatography and then purified by recrystallization.The optimal extraction process was as follows: the herbal residues were extracted by 90% ethanol with solid-liquid ratio of 1∶10 at 85 ℃(reflux) for three times in 1.5,1 and 0.5 h,respectively.The resveratrol in the extract dissolved in water was enriched by D101 macroporous adsorptive resin,followed with separation by silica column chromatography and recrystallization in acetone.The purity of final product was above 99%.