Author
Prior, Ronald | |
WU, XIANLI - ACNC/UAMS |
Submitted to: Book Chapter
Publication Type: Book / Chapter Publication Acceptance Date: 2/15/2007 Publication Date: 9/15/2007 Citation: Prior, R.L., Wu, X. 2007. Hydrophilic and lipophilic antioxidant capacity in foods: Measurement and in vivo implications. In: Shahidi, F., Ho, C., editors. Antioxidant Measurements and Applications. 1st edition. Washington, D.C.: Oxford University Press. p. 67-82. Interpretive Summary: Oxidative stress can cause damage to tissues and cells of the body. Dietary antioxidants can protect against such damage. Thus, although it is important to know what quantities of antioxidants exist in our foods, it is also important to know if these compounds are effective in the body. This paper addresses the question: What can be learned from the measurement of antioxidants in foods? We have conducted several studies of antioxidants in foods and then fed the foods to determine if these antioxidants appeared in the body. We found that measurement of antioxidants in foods does not provide information on what gets into the body after food consumption. Thus, it is necessary to study each food to determine if the antioxidants contained in that food are absorbed and able to provide antioxidant capacity to prevent oxidative damage the results in diseases such as cancer and cardiovascular disease. Technical Abstract: The measurement of both lipophilic and hydrophilic antioxidant capacity in food is possible using the oxygen radical absorbance capacity (ORACFL) assay. Data from these measurements provide a measure of antioxidant capacity using specific biologically relevant free radical sources (usually the peroxyl radical), but different radical sources can be utilized in order to obtain the relative response of different dietary antioxidants to different radical sources. The effects of food processing and of genetics, harvest maturity, and environmental growing conditions on antioxidant components can be evaluated. The in vitro measure of antioxidant capacity provides information on potential for dietary antioxidants to defend against free radical damage in the gastrointestinal tract; however, information on what the in vivo response will be following consumption of the dietary antioxidants may not directly correlate. It is clear that specific phytochemical components in foods are absorbed/metabolized quite differently; thus in vivo techniques are necessary to confirm that antioxidant status will be altered as a result from consumption of the specific source of dietary antioxidants. |