14E-41 |
Growth inhibition of HT-29 colon cancer cells by various berry extracts |
C. ZHAO1, T. Yu1, M. Malik1, L. W. Douglass2, and B. A. Magnuson1. (1) Dept. of Nutrition & Food Science, Univ. of Maryland, 3304 Marie Mount Hall, College Park, MD 20742, (2) Dept. of Animal & Avian Sciences, Univ. of Maryland, 1405 Animal Science/Agricultural Engineering Bldg., College Park, 20742-2311 Justification: High consumption of fruits and vegetables is associated with decreased risk of a variety of cancer types. Research is underway to identify the active chemopreventive compounds in these plants. We have previously reported that anthocyanin-rich extracts from grape, bilberry and chokeberry specially inhibit colon cancer cell, but not normal colon cell growth. Objectives: The purpose of these experiments was to further explore the growth inhibitory effect of other berry extracts and to identify active compounds through fractionation. Materials and methods: Methanol extracts from blueberries, black raspberries and strawberries were evaluated for their ability to inhibit growth of colon adenocarcinoma-derived cells, HT-29, at concentrations ranging from 0-50 µg/mL growth media. Black raspberry extract was fractionated using either water/dichloromethane (1:1) partitioning or silica gel chromatography. Five of the resulting fractions (F001, F003, F004, DM and ET) were compared for their inhibitory effect at concentrations ranging from 0-100 µg/mL growth media. HT-29 cell growth was monitored for 24, 72 and 144 hr using the sulforhodamine B assay and morphological evaluation. Results After exposure to 50 µg/mL blueberry and black raspberry methanol extracts for 24 hour, HT-29 cell growth was inhibited by 26% and 24% respectively. Inhibition was concentration-dependent. All five extracts from black raspberry inhibited the growth of HT-29 cells, but to varying degrees at different time points. After 24 hour, HT-29 cells were inhibited by 30% after exposure to 5 µg/mL ET or DM fractions. Cells exposed to 25 and 50 µg/mL of F003 showed up to 50% inhibition. However, after 144 hour the greatest inhibition was observed in cells exposed to 5 µg/mL F001. Overall, F003 treated HT-29 cells showed the most consistent inhibitory effect. Morphological evaluations indicated that cells treated with black raspberry extracts undergo apoptosis. Significance: Our studies support the hypothesis that blueberry and black raspberry extracts may be protective against cancers of the gastrointestinal tract. They may induce cancer cells to undergo apoptosis.
Session 14E, Nutraceuticals & Functional Foods: General I
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