Despite the national vitamin A and antihelminthic prophylaxis programmes, both intestinal geohelminths and subclinical vitamin A deficiency continue to be prevalent among children in developing countries. Studies on potential synergistic effects of vitamin A supplementation and deworming on retinol status have inconsistent results. The purpose of the present study was to investigate the impacts...

Induction of gap junctional communication (GJC) and antioxidant activities of carotenoids have been considered as biochemical mechanisms underlying the cancer-preventive properties of these compounds. beta-Carotene and other carotenoids, including those lacking provitamin A activity, proved to be active in both these parameters. The beta-carotene analogs retrodehydro-beta-carotene, echinenone, ...

background: oxidative stress in reproductive system leads to sperm dna damage and sperm membrane lipid peroxidation and may play an important role in the pathogenesis of male infertility, especially in idiopathic cases. antioxidants such as carotenoids function against free radical damages. objective : the aim of this study was to determine the levels of lycopene, beta-carotene and retinol in s...

PURPOSE Vitamin A is essential for vision. The key step in the vitamin A biosynthetic pathway is the oxidative cleavage of beta-carotene into retinal by the enzyme beta,beta-carotene-15,15'-monooxygenase (BCO). The purpose of the study was to investigate beta-carotene metabolism and its effects on BCO expression in the human retinal pigment epithelial (RPE) cell line D407. METHODS BCO mRNA an...

*Corresponding Address: LC Nnaji [email protected] In view of the fundamental role of antioxidants such as beta carotene in human nutrition, this study was designed to determine the concentrations of this antioxidant in chicken egg yolks of the preponderant poultry breeds in Nigeria. Among the strains studied include Harco, White Leghorn, and Local chickens. Again, due to instability...

Immunomodulating activities of beta-carotene and carotene-associated carotenoids such as canthaxanthin (beta, beta-carotene-4,4 dione) and astaxanthin (3,3'-dihydroxyl beta, beta-carotene 4,4-dione) were analyzed by in vitro cell culture experiments. (i) beta-Carotene, canthaxanthin and astaxanthin caused significant stimulatory effects on the cell proliferative response of spleen cells and thy...

Three different types of beta-carotene mutants of Phycomyces have been studied. In 2 mutants (Type I) beta-carotene is still the principal carotene but scaled down or up relative to wild type. The carotene mixture of 2 mutants (Type II) consists mainly of phytoene and phytofluene. In Type III (2 mutants) beta-carotene is replaced by lycopene. The examination of the mutants reveals that the rece...

We present a sensitive tracer method, suitable for in vivo human research, that uses beta-[(14)C]carotene coupled with accelerator mass spectrometry (AMS) detection. Using this approach, the concentration-time course of a physiological (306 microgram 200 nCi) oral dose of beta-[(14)C]carotene was determined for 209 days in plasma. Analytes included beta-[(14)C]carotene, [(14)C]retinyl esters, [...

beta-carotene is an antioxidant molecule of commercial value that can be naturally produced by certain microalgae that mostly belong to the genus Dunaliella. So far, nitrogen starvation has been the most efficient condition for enhancing beta-carotene accumulation in Dunaliella. However, while nitrogen starvation promotes beta-carotene accumulation, the cells become non-viable; consequently und...

BACKGROUND Some of the main nutritional reasons for recommending a Mediterranean diet is to prevent metabolic diseases arising through free radical formation. A key constituent compound is beta-carotene which, amongst the carotenoids, displays the greatest provitamin A activity as well as possessing significant antioxidant properties. OBJECTIVES Principally, to determine the relationship betw...