Skip to main content
ARS Home » Southeast Area » Little Rock, Arkansas » Arkansas Children's Nutrition Center » Research » Publications at this Location » Publication #151456
Title: ASSAYS FOR HYDROPHILIC AND LIPOPHILIC ANTIOXIDANT CPACITY (OXYGEN RADICAL ABSORBANCE CAPACITY (ORAC)) OF PLASMA AND OTHER BIOLOGICAL AND FOOD SAMPLES

Author
item Prior, Ronald
item HOANG, HA - ACNC
item GU, LIWEI - UAMS
item BACCHIOCCA, MARA - ACNC
item HOWARD, LUKE - UNIV/ARKANSAS
item HAMPSCH-WOODILL, MAUREEN - BRUNSWICK LABORATORIES
item HUANG, DEJIAN - BRUNSWICK LABORATORIES
item OU, BOXIN - BRUNSWICK LABORATORIES
item JACOB, ROBERT - WESTERN HUMAN RESEARCH CT

Submitted to: Journal of Agricultural and Food Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/25/2003
Publication Date: 4/29/2003
Citation: PRIOR, R.L., HOANG, H., GU, L., BACCHIOCCA, M., HOWARD, L., HAMPSCH-WOODILL, M., HUANG, D., OU, B., JACOB, R. ASSAYS FOR HYDROPHILIC AND LIPOPHILIC ANTIOXIDANT CPACITY (OXYGEN RADICAL ABSORBANCE CAPACITY (ORAC)) OF PLASMA AND OTHER BIOLOGICAL AND FOOD SAMPLES. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY. 2003. v. 51. p. 3273-3279.

Interpretive Summary: Oxidation of various chemical components of cells is thought to be the major process leading to tissue damage and diseases of several types. Dietary antioxidants are thought to counteract these actions and provide a degree of protection against this damaging oxidative process. Cells have components that are soluble in lipids (fat) or water. Knowing the levels of antioxidants in the lipid soluble or water soluble portion of cells is important in determining how much antioxidant rich foods are required to provide protection against cellular oxidation. This study was conducted to develop methods of analysis of water soluble and lipid soluble antioxidant capacity in biological samples and foods were developed using modifications of the Oxygen Radical Absorbing Capacity (ORACFL) procedure. These methods, for the first time, provide the ability to obtain a measure of 'Total Antioxidant Capacity' in the protein free plasma using the same peroxyl radical generator for both lipid and water soluble antioxidants. Lipid soluble antioxidants represented 30-40% of the total antioxidant capacity of protein free plasma. Lipophilic and hydrophilic antioxidants were efficiently partitioned between hexane and aqueous solvents. Conditions for controlling assay variability were validated in different laboratories. Methods are described for application of the assay techniques to other types of biological and food samples. These methods are being used to develop a database of antioxidant capacity of foods which will be part of the USDA food database.

Technical Abstract: To assess the physiologic effects of cherry consumption, we measured plasma urate, antioxidant, and inflammatory markers in ten healthy women fed Bing sweet cherries. The women, age 22-40 y, consumed two servings (280 g) of cherries after an overnight fast. Blood and urine samples were taken before the cherry dose, and at 1.5, 3, and 5 h postdose. Plasma urate decreased at 5 h postdose, mean ± SEM = 183 ± 15 µmol/L compared to predose baseline of 214 ± 13 µmol/L (p<0.05). Urinary urate increased post-dose, with peak excretion of 350 ± 33 µmol/mmol creatinine at 3 h postdose compared to 202 ± 13 at baseline (p<0.01). Plasma C-reactive protein (CRP) and nitric oxide (NO) concentrations decreased marginally at 3 h postdose (p<0.1) while plasma albumin and TNF-alpha were unchanged. The vitamin C content of the cherries was solely as dehydroascorbic acid, but postdose increases in plasma ascorbic acid indicated that dehydroascorbic acid in fruits is bioavailable as vitamin C. The decrease in plasma urate following cherry consumption supports the anti-gout reputation of cherries. The trend toward decreased inflammatory indices CRP and NO adds to in vitro evidence that compounds in cherries may inhibit inflammatory pathways.