14E-7 |
Antioxidant activity of oryzanol as determined using an in vitro cell culture model |
C. C. J. HUANG and J. S. GODBER. Dept. of Food Science, Louisiana State Univ. Agricultural Center, 111 Food Science Bldg., Baton Rouge, LA 70803-4200 Oryzanol may have functional capacity in several diseases that likely involve in vivo oxidative reactions such as coronary artery disease and cancer. Oryzanol has been found to have antioxidant activity using a cholesterol oxidation model compared to vitamin E. This is the first time that an in vitro cell culture model was developed to study the antioxidant activity of oryzanol. Our objective was to develop an in vitro cell culture model and use it to evaluate antioxidant activity of oryzanol compared to a-tocopherol. Mouse lymph axillary endothelial cell line, SVEC4-10 (ATCC CRL-2181), MTT for cell viability measurement and tert-butyl hydroperoxide (tBHP) as the oxidation agent were used. Oryzanol emulsion was prepared using ethanol, phosphatidylcholine and bovine serum albumin. An in vitro cell model was established and proven to be capable of distinguishing antioxidant activity of oryzanol from a-tocopherol. It was found that SVEC4-10 cell line had fast metabolism and consequently could be used to determine antioxidant activity of a test substance in a relatively rapid manner. Critical parameters included the emulsion preparation of hydrophobic compounds, consistent management of cell culture, the control of tBHP oxidation conditions and the selection of cell viability detection methods compatible with the cell line and test substance. Our results showed that oryzanol possessed antioxidant activity in terms of reducing tBHP oxidation damage on cellular mitochondrial activity. Among the three major components of oryzanol, cycloartenyl ferulate, 24-methylene cycloartanyl ferulate and campesteryl ferulate, 24-methylene cycloartanyl ferulate was found to be more effective. In some situations, oryzanol could present more powerful antioxidant activity than a-tocopherol (81.8% cell viability when incubated with oryzanol after 1-hour oxidation compared to 54.5% with the control and 74.6% with a-tocopherol). This could imply functionality in a number of chronic diseases such as coronary artery disease and cancer.
Session 14E, Nutraceuticals & Functional Foods: General I
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