title: Bioavailability of iron from spinach using an in vitro/human Caco-2 cell bioassay model.
abstract: Spinach (Spinacia oleracea) cv Whitney was tested for iron bioavailabilty using an in vitro human intestinal cell culture ferritin bioassay technique previously developed. Spinach was cultured in a growth chamber for 33 days, harvested, and freeze-dried. Total iron in the samples was an average of 71 micrograms/g dry weight. Spinach was digested in vitro (pepsin and 0.1 M HCl followed by pancreatin and 0.1 M NaHCO3) with and without the addition of supplemental ascorbic acid. Caco-2 cell cultures were used to determine iron bioavailability from the spinach mixtures. Production of the iron-binding protein ferritin in the Caco-2 cells showed the supplemental ascorbic acid doubled bioavailability of iron from spinach. The data show fresh spinach is a poor source of iron, and emphasize the importance of evaluation of whole meals rather than single food items. The data support the usefulness of the in vitro/Caco-2 cell ferritin bioassay model for prescreening of space flight diets for bioavailable iron.
authors.affiliation: Controlled Environment Agriculture Program, Department of Biological and Environmental Engineering, Cornell University, Ithaca, NY 14853, USA. CFJ4@cornell.edu
authors.forename: Corinne J
authors.initials: CJ
authors.lastname: Rutzke
authors.forename: Raymond P
authors.initials: RP
authors.lastname: Glahn
authors.forename: Michael A
authors.initials: MA
authors.lastname: Rutzke
authors.forename: Ross M
authors.initials: RM
authors.lastname: Welch
authors.forename: Robert W
authors.initials: RW
authors.lastname: Langhans
authors.forename: Louis D
authors.initials: LD
authors.lastname: Albright
authors.forename: Gerald F
authors.initials: GF
authors.lastname: Combs
authors.forename: Raymond M
authors.initials: RM
authors.lastname: Wheeler
mesh_terms: D001205:Ascorbic Acid / Q000008:administration & dosage / Q000502:physiology*; D001682:Biological Availability; D018938:Caco-2 Cells; D004305:Dose-Response Relationship, Drug; D005293:Ferritins / Q000096:biosynthesis*; D006801:Humans; D019266:Iron, Dietary / Q000493:pharmacokinetics*; D008954:Models, Biological; D009753:Nutritive Value; D010940:Plant Proteins / Q000032:analysis; D011237:Predictive Value of Tests; D013026:Space Flight; D018724:Spinacia oleracea / Q000737:chemistry* / Q000254:growth & development
chemical_list: D019266:Iron, Dietary; D010940:Plant Proteins; D005293:Ferritins; D001205:Ascorbic Acid