Abstract: 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.

Key words: Caribbean pine bark, procyanidins, ultrasonic wave extraction, microwave-assisted extraction