114E-26 |
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H.-S. CHUN, Korea Food Research Institute, San 46-1, Baekhyun-dong, Bundang-gu, Sungnam, 463-746, South Korea and H.-J. Kim, Food chemistry and biotechnology division, Korea Food Research Institute, San 46-1, Backhyun-dong, Bundang-gu, Sungnam Si, Kyonggido, 463-420, South Korea. In vitro assay systems are the first stage in research on evaluating food functionality. These systems have advantages over in vivo experimental systems including more convenient maintenance, lower cost and relatively shorter time span for results. By using an in vitro model, such as a human-derived cell line, useful information can sometimes be obtained. However, active food components or extracts have diverse physicochemical natures such as volatility, solubility, color pigment itself that possibly yield false negative or false positive results using cell-based assay systems. With regards special considerations should be needed in evaluating food functionality. Our objective was to determine the effects of physicochemical characteristics of food components such as volatility, solubility and color pigments on in vitro cell proliferation assay. HepG2 (hepatoma, human) and U-937 (lymphoma, human) were used as cell proliferation assay. Eight test samples having diverse physicochemical properties were evaluated. MTT, MTS, LDH and SRB assays were used to determine the cell proliferation. In test of volatile samples, false negative results could be obtained due to their loss in culture medium during incubation and were prevented by addition of inclusion vehicle. Application of carboxymethylcellulose or gelatin prevented the false positive results of insoluble materials that inhibited the cell proliferation by direct physical contact during culture. Efficiencies of cell proliferation assay methods in testing of samples having color pigment itself were compared. Additionally, correlations between cell proliferation assay methods were also determined. These results suggest that selection of proper assay methods and use of supplementary aids for volatile or insoluble samples successfully minimized the possible false positive or false negative results due to diverse physicochemical characteristics of food components.
Session 114E, Nutraceuticals & Functional Foods: Bioactivity measurement and mechanism
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