Micellarization of β-carotene during in vitro digestion of maize and uptake by Caco-2 intestinal cells is minimally affected by xanthophylls
Creators:Thakkar, Sagar K.
Advisor:Failla, Mark L.
MetadataShow full item record
Series/Report no.:Interdisciplinary Ph.D. Program in Nutrition - OSUN. Graduate student poster competition, 2008
Currently consumed varieties of maize contain limited pro-vitamin A (VA) carotenoids despite relatively high levels of lutein (LUT) and zeaxanthin (ZEA). Here we determined the relative bioaccessibility of pro-VA carotenoids and their interactions with xanthophylls. First, we examined four accessions of maize containing 0.4 – 11.3 µg/g β-carotene (BC) + β-cryptoxanthin (BCX) with ratios of xanthophylls to pro-VA carotenoids ranging from 1.9 – 7.0. Recovery of carotenoids in cooked maize exceeded 80% after simulated digestion. Mean efficiencies of micellarization of BC, BCX, LUT and ZEA were 16.7, 27.7, 30.3 and 27.9%, respectively, and were independent of the ratio of xanthophylls to pro-VA carotenoids. We also digested white maize to which 3.3 µg/g BC in extra light olive oil (2% v/w) and increasing amounts of LUT (0 – 33.3 µg/g) were added. Efficiency of micellarization of BC was 21.7% in the absence of LUT and increased to 30.2% (P < 0.05) when LUT content was 7x that of BC. Incorporation of BC into synthetic micelles also increased (P < 0.05) when LUT to BC ratio was ≥10. Caco-2 cells accumulated 270, 240 and 180 pmol BC/mg cell protein (P < 0.05) in absence of LUT and at LUT to BC ratios of 7 and 13, respectively. These results suggest that the potential bioavailability of pro-VA carotenoids in maize does not appear to be markedly affected by the relative levels of xanthophylls found in cultivars of maize. Supported in part by HarvestPlus & OARDC.
This study was supported by funding from HarvestPlus and Ohio Agricultural Research and Development Center (OARDC).
Items in Knowledge Bank are protected by copyright, with all rights reserved, unless otherwise indicated.