Submitted to: Journal of Agricultural and Food Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/5/2003
Publication Date: 11/8/2003
Citation: Prior, R.L., Gu, L., Kelm, M.A., Hammerstone, J.F., Beecher, G., Holden, J., Haytowitz, D. 2003. Screening of foods containing proanthocyanidins and their structural characterization using lc-ms/ms and thiolytic degradation. Journal of Agricultural and Food Chemistry. 51(25):7513-7521.
Interpretive Summary: Proanthocyanidins are large complex compounds found in many foods. These substances have been shown to have potential health benefits. However, little is known about their dietary intake because quantitative information on the proanthocyanidin profiles in foods is lacking. A method was developed and applied to screen for proanthocyanidins in 88 different kinds of foods. Thirty-nine foods were found to contain proanthocyanidins. These foods include 19 kinds of fruits, 8 cereals/beans, 7 nuts, 2 beverages, 2 spices, and one vegetable. Twenty-five kinds of foods were found to contain both small and very large proanthocyanidins, and the other 14 foods contained only the smaller proanthcyanidin compounds. The structure of proanthocyanidins in pinto bean, raspberry, strawberry, and almond were found to have unique structures, different than that in plum, avocado, peanut, curry, cranberry, and cinnamon. This study has demonstrated that proanthocyanidins account for a major fraction of the total flavonoids ingested in the Western diet. Information from this study will be used to construct a database of proanthocyanidins in foods which can be used in studies to evaluate the dietary intake of these compounds.
Technical Abstract: A normal-phase HPLC-MS/MS method was applied to screen for proanthocyanidins in 88 different kinds of foods. Thirty-nine foods were found to contain proanthocyanidins. These foods include 19 kinds of fruits, eight cereals/beans, seven nuts, two beverages, two spices, and one vegetable. Twenty-five kinds of foods were found to contain both oligomeric (DP 10) and polymeric proanthocyanidins (DP > 10), and the other 14 foods contained only oligomers. Procyanidins with B-type linkages were detected as the only components in 21 foods and also as principal components in the others. Propelargonidins were identified in pinto bean, raspberry, strawberry, and almond, etc. Plum, avocado, peanut, curry, and cinnamon were identified as potential sources of A-type proanthocyanidins in addition to cranberry. Thiolytic degradation and MS/MS analyses indicated that the A-type linkages are present as a terminal unit in plum or between the extension units in curry, cinnamon, and avocado, whereas A-type linkages exist at both positions in cranberry and peanut. Keywords: Catechin; propelargonidin; procyanidin; proanthocyanidins; tannins; foods