title: Supplemental inulin does not enhance iron bioavailability to Caco-2 cells from milk- or soy-based, probiotic-containing, yogurts but incubation at 37°C does.
abstract: The in vitro effects of supplemental inulin (4%) on iron (Fe) availability in two different probiotic-containing yogurts were examined. Milk or soy-based yogurts, with and without inulin, were incubated (37°C) for 48h or without any incubation before comparison by an in vitro gastrointestinal digestion/Caco-2 cell culture model was used to assess iron bioavailability. The dialysable Fe fraction, cell ferritin formation, and cell associated Fe were monitored. Supplemental inulin decreased dialysable Fe only in non-incubated milk-based yogurt. In both yogurts incubation by itself increased dialysable Fe, and inulin increased the latter only in soy-based yogurt. Cellular ferritin concentration were higher after exposure to non-incubated milk-based than soy-based yogurt, although, after incubation the latter induced the highest ferritin formation. These data suggest that inulin does not have a direct effect on Fe bioavailability in the small intestine, and that probiotic bacteria play an enhancing role on Fe bioavailability.
authors.affiliation: Department of Food Science, Cornell University, 216 Stocking Hall, Ithaca, New York 14853, United States. Electronic address: jml259@cornell.edu.
authors.forename: José Moisés
authors.initials: JM
authors.lastname: Laparra
authors.affiliation: Department of Food Science, Cornell University, 216 Stocking Hall, Ithaca, New York 14853, United States.
authors.forename: Elad
authors.initials: E
authors.lastname: Tako
authors.affiliation: US Plant, Soil, and Nutrition Laboratory, Agricultural Research Service, US Department of Agriculture, Ithaca, New York 14853, United States.
authors.forename: Raymond P
authors.initials: RP
authors.lastname: Glahn
authors.affiliation: Department of Food Science, Cornell University, 216 Stocking Hall, Ithaca, New York 14853, United States.
authors.forename: Dennis D
authors.initials: DD
authors.lastname: Miller
keywords: Caco-2 cells; Inulin; Iron bioavailability; Prebiotic; Yogurts