Send Page to a friendPhenolic compounds from blueberries can inhibit colon cancer cell proliferation and induce apoptosis.
J Agric Food Chem. 2005 Sep 7;53(18):7320-9.
Yi W, Fischer J, Krewer G, Akoh CC.
Department of Food Science and Technology, The University of Georgia, Athens, Georgia 30602-7610, USA.
Research has shown that diets rich in phenolic compounds may be associated with lower risks of several chronic diseases including cancer. This study systematically evaluated the bioactivities of phenolic compounds in rabbiteye blueberries and assessed their potential anti-proliferation and apoptosis induction effects using two colon cancer cell lines, HT-29 and Caco-2. Polyphenols in three blueberry cultivars, Briteblue, Tifblue, and Powderblue, were extracted and freeze-dried. The extracts were further separated into phenolic acids, tannins, flavonols, and anthocyanins using an HLB cartridge and LH20 column. Some individual phenolic acids and flavonoids were identified by HPLC with 90% purity in anthocyanin fractions. The dried extracts and fractions were added to the cell culture medium to test for anti-proliferation activities and induction of apoptosis. Flavonol and tannin fractions resulted in 50% inhibition of cell proliferation at concentrations of 70-100 and 50-100 microg/mL in HT-29 and Caco-2 cells, respectively. The phenolic acid fraction showed relatively lower bioactivities with 50% inhibition at approximately 1000 microg/mL. The greatest anti-proliferation effect among all four fractions was from the anthocyanin fractions. Both HT-29 and Caco-2 cell growth was significantly inhibited by 50% by the anthocyanin fractions at concentrations of 15-50 microg/mL. Anthocyanin fractions also resulted in 2-7 times increases in DNA fragmentation, indicating the induction of apoptosis. The effective dosage levels are close to the reported range of anthocyanin concentrations in rat plasma. These findings suggest that blueberry intake may reduce colon cancer risk.
Specific phenolic antioxidants isolated from blueberries were effective in reducing activity of colon cancer cells. This and a variety of other studies indicate that chemical constituents of dark berries have anti-cancer activity.
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