Extraction of proanthocyanidins from grape seed

The percentage of phenols (calculated as GAE) in grape seed is about 4.85%, proanthocyanidin about 3.05%(10%moisture of raw materials). So exploitation of grape seeds has great value in use. The research results showed that when the grapeseed powder of 130～150 mesh was extracted by 70% acetone with stirring 40min at 20?, the extract ratio of proanthocyanidinwas the highest of 99.11%. At a constant temperature, the more power of ultrasonic wave, the higher extract ratio ofproanthocyanidin. The extract ratio of proanthocyanidin in grape seed dried by vacuum-desiccator was 12.61% higher than driednaturally.