Study on the Extraction Technology of Procyanidins from Caribbean Pine Bark

The method and technological conditions for extraction of extract procyanidins from Caribbean pine bark were systema-tically investigated.Three different extraction methods,including conventional solvent extraction,ultrasonic wave extraction and microwave-assisted extraction were compared.The results indicated that the extraction yield of procyanidins was highest when 70 % ethanol was used as solvent.Ultrasonic wave extraction and microwave-assisted extraction are better among the three extraction methods.Ultrasonic wave extraction can get a high yield in a short-time extraction process.However in microwave-assisted extraction the solvent extraction time after the effect of microwave should be prolonged to obtain a high extraction yield.For ultrasonic wave extraction,the optimum conditions were as follows:extraction temperature 50 ℃,ultrasonic wave power 100 W,the ratio of raw materials to ethanol 1∶11,and extraction time 1.5 h.The optimum conditions of microwave-assisted extraction were microwave power 200 W,radiation time with microwave 30 s,the ratio of solid to liquid 1∶11,extraction temperature 50 ℃,and extraction time 6 h.As the results,the yields of procyanidins from Caribbean pine bark were 7.47 % and 7.69 % respectively under above conditions.