Abstract: The aim of this study was to optimize technical conditions for ultrasonic-assisted ethanol extraction, cellulase hydrolysis-based extraction and microwave-assisted ethanol extraction of proanthocyanidins from grape seed power using one-factor-at-a-time coupled with orthogonal array design method. Microwave-assisted extraction was found to be the best of the three methods, and the optimal process conditions were ethanol concentration of 80%, material-to-liquid ratio of 1:25 (g/mL), microwave treatment time of 40 s and microwave power of 115 W. Under these conditions, the extraction rate of proanthocyanidins was 10.70%.

Key words: grape seed, proanthocyanidins, microwave, cellulose, ultrasonic