Submitted to: Institute of Food Technologists
Publication Type: Abstract Only
Publication Acceptance Date: April 10, 2006
Publication Date: June 1, 2006
Citation: Collins, J.K., Perkins Veazie, P.M., Arjmandi, B.H., Claypool, P.I., Clevidence, B.A. 2006. Antioxidants Status of Humans after Intervention with Watermelon and Tomato Juice [Abstract}. Institute of Food Technologists Annual Meeting Technical Program Abstracts. p. 111.
Watermelon and tomato are both excellent sources of lycopene with similar compositions of other carotenoids. In plant extract studies, both foods exhibited strong antioxidant activity. Increased antioxidant capacity of plasma as measured by ferric reducing ability of plasma (FRAP) and malondialdehyde formation products (MDA) was found with processed tomato diet intervention. No studies have been conducted to measure the antioxidant capacity of plasma following watermelon intervention.
The objective of this study was to measure the plasma antioxidant status of middle-aged adults after supplementing with two lycopene containing foods, watermelon and tomato juice.
This study used a subset of subjects from a larger study that was designed to assess the bioavailabilty of lycopene from watermelon and tomato juice. Each of ten subjects consumed in a crossover design, a controlled diet supplemented with 1) watermelon juice (20mg lycopene, 24mg total carotenoids/day), 2) tomato juice (18.4mg lycopene, 22mg total carotenoids/day), or 3) no juice (control) for three weeks. Plasma collected weekly was analyzed for the antioxidant biomarkers of MDA, plasma glutathione peroxidase (GPX) and FRAP. Data were analyzed using Proc Mixed Procedure and associations between antioxidant measures were identified by Pearson’s product moment correlation analysis.
Supplementing for three weeks with tomato or watermelon juice did not change the plasma antioxidant status of the subjects as measured by FRAP, MDA or GPX. The results of MDA assay were positively correlated to FRAP assay (p=0.001, 0.474 correlation coefficient) with a linear relationship (r**2 =0.2321), while GPX was not correlated with either assay.
Although the bioavailability of lycopene from watermelon or tomato juice was similar, there were no differences between the treatments and control for plasma antioxidant status. However, the MDA and FRAP data were correlated and these assays may provide dual measurements for determining the antioxidant status in humans.