Modeling the dose effects of soybean oil in salad dressing on carotenoid and fat-soluble vitamin bioavailability in salad vegetables.

Previously, we showed that vegetable oil is necessary for carotenoid absorption from salad vegetables. Research is needed to better define the dose effect and its interindividual variation for carotenoids and fat-soluble vitamins. The objective was to model the dose-response relation between the amount of soybean oil in salad dressing and the absorption of ) carotenoids, phylloquinone, and tocopherols in salad vegetables and ) retinyl palmitate formed from the provitamin A carotenoids.

Genetic architecture controlling variation in grain carotenoid composition and concentrations in two maize populations.

Genetic control of maize grain carotenoid profiles is coordinated through several loci distributed throughout three secondary metabolic pathways, most of which exhibit additive, and more importantly, pleiotropic effects. The genetic basis for the variation in maize grain carotenoid concentrations was investigated in two F2:3 populations, DEexp × CI7 and A619 × SC55, derived from high total carotenoid and high β-carotene inbred lines. A comparison of grain carotenoid concentrations from population DEexp × CI7 grown in different environments revealed significantly higher concentrations and greater trait variation in samples harvested from a subtropical environment relative to those from a temperate environment.

Vitamin A equivalence of the ß-carotene in ß-carotene-biofortified maize porridge consumed by women.

Background: β-Carotene-biofortified maize is being developed through plant breeding as a sustainable agronomic approach to alleviate vitamin A deficiency.

Objective: Our objective was to quantify the vitamin A equivalence of the β-carotene in β-carotene-biofortified maize based on consumption of a single serving of maize porridge.

Design: Six healthy women each consumed three 250-g portions of maize porridge as follows: 1) β-carotene-biofortified maize porridge containing 527 μg (0.

Retention of provitamin A carotenoids in high beta-carotene maize (Zea mays) during traditional African household processing.

High beta-carotene maize, biofortified with beta-carotene through plant breeding, is being developed as a cost-effective, sustainable agronomic approach to alleviating the problem of vitamin A deficiency in Africa. We used high beta-carotene maize (10.49+/-0.

Use of a 13C tracer to investigate lutein as a ligand for plasma transthyretin in humans.

The selective accumulation of lutein in the macula of the human retina is likely to be mediated by specific transport and/or binding proteins. Our objective was to determine whether transthyretin (TTR) is a plasma transport protein for lutein. We used a biosynthetic 13C-lutein tracer and GC-combustion interfaced-isotope ratio MS to gain the requisite sensitivity to detect the minute amounts of lutein expected as a physiological ligand for TTR.

Carotenoid bioavailability is higher from salads ingested with full-fat than with fat-reduced salad dressings as measured with electrochemical detection.

Background: The amount of dietary fat required for optimal bioavailability of carotenoids in plant matrices is not clearly defined.

Objective: The objective was to quantify the appearance of carotenoids in plasma chylomicrons after subjects ingested fresh vegetable salads with fat-free, reduced-fat, or full-fat salad dressings.

Design: The subjects (n = 7) each consumed 3 salads consisting of equivalent amounts of spinach, romaine lettuce, cherry tomatoes, and carrots with salad dressings containing 0, 6, or 28 g canola oil.