Abstract: Objective: To explore the microwave-assisted extraction of procyanidins from raspberry seeds and screen the optimal extraction parameters. Methods: The response surface design was used to investigate the effects of ethanol concentration, microwave power, material-liquid ratio and microwave time on extraction rate of procyanidins from raspberry seeds. Results: The optimal extraction conditions were ethanol concentration of 60%, ultrasonic power of 300 W, material/liquid ratio of 1:10 (g/mL) and microwave extraction time of 3 min. Under the optimal extraction conditions, the extraction rate of procyanidins from raspberry seeds was up to 7.19 mg/g, which exhibited a 3-fold enhancement compared with traditional water extraction. Conclusion: The optimized microwave extraction process for procyanidins from raspberry seeds is highly efficient and less time consumption.

Key words: raspberry seeds, procyanidins, microwave-assisted extraction