Submitted to: Journal of Nutritional Biochemistry
Publication Type: Review Article
Publication Acceptance Date: January 31, 1997
Publication Date: N/A
Interpretive Summary: Interpretive Summary not needed for this 115.
Technical Abstract: Although plant foods provide an array of nutrients in the human diet, our knowledge of how efficiently these nutrients are absorbed has been limited by our ability to selectively monitor their absorption from a complex food matrix. Intrinsic labeling of plants with low-abundance stable isotopes can provide a safe, traceable product to investigate absorptive phenomena in the gut. Various techniques, including hydroponic culture, stem injection, and atmospheric labeling, have been used to introduce isotopes of either minerals or carbon to the plant. New, alternative possibilities exist for labeling plants with deuterium through the use of heavy water, or for using isolated root cultures. Each labeling situation offers some unique concern, related to the plant, the nutrient, or the isotope expense, that must be addressed in order to generate a useful and affordable product. Attention to the mechanisms and pathways by which a specific nutrient is transported throughout the plant will aid in the selection of an effective labeling approach that will (1) maximize the recovery of isotope in the edible tissues, and (2) ensure that the isotope is incorporated into endogenous compounds and compartments in the same manner as that of the normal high-abundance isotopes. Intrinsically labeled plants may be used in an unlimited number of human bioavailability investigations focusing on essential nutrients, secondary plant metabolites, or unique phytochemicals.