Summary: Precursor forms of vitamins.
Cooperstone J, Goetz H, Riedl K, Harrison E, Schwartz S, Kopec R. Relative contribution of ?-carotene to postprandial vitamin A concentrations in healthy humans after carrot consumption. Am J Clin Nutr. 2017;106:59-66 pubmed publisher
..This trial was registered at clinicaltrials.gov as NCT01432210. ..
Ford J, Green J, Lietz G, Oxley A, Green M. A Simple Plasma Retinol Isotope Ratio Method for Estimating ?-Carotene Relative Bioefficacy in Humans: Validation with the Use of Model-Based Compartmental Analysis. J Nutr. 2017;147:1806-1814 pubmed publisher
..The method also provides information about the contributions of absorptive and postabsorptive conversion to total bioefficacy if an additional sample is taken at 1 d. ..
Oparinde A, Abdoulaye T, Mignouna D, Bamire A. Will farmers intend to cultivate Provitamin A genetically modified (GM) cassava in Nigeria? Evidence from a k-means segmentation analysis of beliefs and attitudes. PLoS ONE. 2017;12:e0179427 pubmed publisher
..It was estimated that only 25% of the surveyed population of farmers was highly opposed to cultivating Provitamin A GM cassava. ..
Schaub P, Wüst F, Koschmieder J, Yu Q, Virk P, Tohme J, et al
. Nonenzymatic ?-Carotene Degradation in Provitamin A-Biofortified Crop Plants. J Agric Food Chem. 2017;65:6588-6598 pubmed publisher
..This reveals a substantial nonenzymatic proportion of carotene decay and corroborates the quantitative relevance of highly oxidized ?-carotene polymers that form in all plant tissues investigated. ..
Sheftel J, Gannon B, Davis C, Tanumihardjo S. Provitamin A-biofortified maize consumption increases serum xanthophylls and 13C-natural abundance of retinol in Zambian children. Exp Biol Med (Maywood). 2017;242:1508-1514 pubmed publisher
..The combined analyses of serum zeaxanthin specifically and 13C-natural abundance of retinol could prove useful in effectiveness studies between orange maize adopters and non-adopters. ..