Research Overview

Dr. Prior’s research has focused on aspects related to the health effects of dietary fruits and vegetables. One focus has been to develop analytical techniques whereby we can quantitate many of the phytochemicals in fruits and vegetables. Results from these efforts have led to the expansion of the flavonoid database in the USDA Food Nutrient Database with the addition of data on anthocyanins, proanthocyanidins and antioxidant capacity (ORACFL). This has provided the first comprehensive set of data on concentrations of procyanidins, anthocyanins, and antioxidant capacity in commonly consumed foods in the U.S., and will make it possible to compute dietary intakes of these phytochemicals in many of the epidemiology studies conducted in this country.

Furthermore, Dr. Prior’s research has provided leadership in understanding the metabolism of anthocyanins during the absorption process. Further studies have begun to elucidate some of the phenolic acids and other metabolites that are produced in the gastrointestinal tract as a result of microbial metabolism of proanthocyanidins.

Proanthocyanidins seem to have the ability to increase the sensitivity of insulin. His recent work has focused on application of some of this information to the understanding of how these phytochemicals may prevent the development of metabolic syndrome and alter insulin sensitivity.

Key Publications

Prior, R. L.; Gu, L.; Wu, X.; Jacob, R. A.; Sotoudeh, G.; Kader, A. A.; Cook, R. A., Plasma antioxidant capacity changes following a meal be used as a measure of the ability of a food to alter in vivo antioxidant status. J. Amer. Coll. Nutr. 26, (2), 170-181, 2007.

Prior, R. L.; Wu, X.; Gu, L., Perspective: Flavonoid metabolism and challenges to understanding mechanisms of health effects. J. Sci. Food Agric. 86, 2487-2491, 2006.

Prior, R. L.; Wu, X., Anthocyanins: structural characteristics that result in unique metabolic patterns and biological activities. Free Radic Res 40, (10), 1014-28, 2006.

Wu, X.; Beecher, G. R.; Holden, J. M.; Haytowitz, D. B.; Gebhardt, S. E.; Prior, R. L., Concentrations of anthocyanins in common foods in the United States and estimation of normal consumption. J Agric Food Chem 54, (11), 4069-75, 2006.

Prior, R. L.; Wu, X.; Schaich, K., Standardized methods for the determinations antioxidant capacity and phenolics in foods and dietary supplements. J. Agric. Food Chem 53, 4290-4302, 2005.

Wu, X.; Pittman, H. E.; McKay, S.; Prior, R. L., Aglycones and sugar moieties alter anthocyanin absorption and metabolism following berry consumption in the weanling pig. J. Nutr. 135, 2417-2424, 2005.

Prior, R. L.; Gu, L., Prevalence, structural diversity and biological significance of proanthocyanidins (Condensed Tannins) in the American diet. Phytochemistry 66, (18), 2263-2279, 2005.

*To find additional publications by this author, please visit Pubmed Central, a National Institutes of Health-operated site for electronic distribution of life sciences research reports.

Research Support

USDA/ARS - The Effects of Dietary Factors During Development on Long-Term Health Consequences.

USDA/NRI - Processing Effects on the Content and Absorption of Grape and Berry Polyphenolics - Co-PI

Masterfoods Inc. – Analytical Measurement System: Single Lab Validation and an External Multi-Lab AOAC Peer Validation - PI

Oregon Berry Commission - Berry Anthocyanins and the Prevention of Obesity - PI