Micellarization of β-carotene during in vitro digestion of maize and uptake by Caco-2 intestinal cells is minimally affected by xanthophylls

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)

Past, Present and Future of Human Milk Research

Human milk is the best source of infant nutrition and is recognized as a biological fluid vital for optimal growth and development. It has established short- and long-term benefits to infants and mothers. Sapiens\u27 milk has coevolved with mammalian species for millennia which has resulted in this remarkable secretory product of nutrient-rich milk. The nutritional composition and nonnutritive bioactive factors in human milk are uniquely appropriate for the infant, which provides survival and healthy development. Research over the past 2-3 decades focused on increasing the understanding about the composition of human milk and different factors that influence the composition such as stage of lactation, impact of maternal diet, geographical location, gestational age at infant birth, and circadian rhythm. Presently, collaborative efforts are ongoing in communicating the clinical advantages of human milk composition in relation to public health. Different groups are also working on the establishment of reference in the form of databases using reference and growth standard methodology. Toward the future, with computational and modeling methods, the next stage is to understand human milk as a biological system. Cellular agriculture is also the next exciting field of human milk research