Antioxidant and antitumor effects and immunomodulatory activities of crude and purified polyphenol extract from blueberries

The antioxidant and antitumor effects as well as the immunomodulatory activities of crude and purified polyphenol extract from blueberries were investigated. The antioxidant and antitumor effects of the polyphenol extract were measured both in vitro and in vivo, and their effect on the immune systems of CD-1 tumor-bearing mice were also analyzed. In vitro assays demonstrated that blueberry purified polyphenol extract （BBPP） exhibited higher antioxidant activities than blueberry crude polyphenol extract （BBCP）, but the opposite effect was observed in vivo. Both the in vitro and in vivo antitumor activity and the immunity assay showed that BBCP not only inhibited tumor growth, but also significantly improved the immunity of the mice. According to physical and histological studies, the CD-1 tumor-bearing mice treated with the polyphenol extract, especially high doses of BBCP experienced a higher quality of life than the positive control group （treated with cyclophosphamide）. These results indicate that BBCP has significant antioxidant and antitumor activities and that it can enhance the immunity of CD-1 tumor-bearing mice.