ARS | Publication request: ABSORPTION OF BETA-CAROTENE FROM CARBON-13 LABELED KALE

Submitted to: Experimental Biology
Publication Type: Abstract Only
Publication Acceptance Date: April 15, 2001
Publication Date: April 15, 2001
Citation: Novotny Dura, J., Britz, S.J., Pawlosky, R.J., Harrison, D.J., Kelm, M.A., Flanagan, V.P., Brown, E., Beecher, G.R., Clevidence, B.A. 2001. Absorption of beta-carotene from carbon-13 labeled kale. Experimental Biology.

Technical Abstract: Bioavailability of nutrients from fruits and vegetables is key to determining how well they provide health benefits. The objective of this study was to quantitate the absorption of beta-carotene from a green, leafy vegetable. Kale was grown in an environmental chamber to be entirely labeled with carbon-13. The growth chamber was sealed, and the only source of carbon available to kale plants during the growth cycle was carbon-13. Nutrients were found to be labeled at >97%. Upon harvest, the labeled kale was fed to a healthy male volunteer as a single 400 gram dose with 30 grams of oil. Serial blood samples were collected several times on the dose day, and several times per week for 6 weeks following the dose. Plasma was analyzed for labeled beta-carotene and retinol by LC-MS and GC-MS, respectively. Compartmental modeling was used to analyze the plasma data. The plasma showed a significant rise in C13-beta-carotene and C13-retinol following ingestion of the labeled kale, representing substantial absorption of the beta-carotene from the plant matrix. The labeled beta-carotene was detectable for 6 weeks following the dose, and the labeled retinol was detectable for over 3 weeks following the dose. In conclusion, labeling of green, leafy vegetables with carbon-13 is a feasible way to study bioavailabiltiy of nutrients from plant foods.