When the sub-core complex of photosystem II, D1/D2, is irradiated at 436 or 415 nm (absorption by chlorophyll and pheophytin and ß-carotene) or 540 nm (absorption primarily by pheophytin), the low temperature fluorescence spectrum has two maxima, at 685 and 674 nm. This shows the existence of at least two different fluorescent forms of chlorophyll (chlorophyll a and perhaps pheophytin a). When ...

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, ...

We measured carotene in the livers of two patients receiving beta-carotene therapy for photosensitivity. In both patients, the amount of carotene was within reported ranges for patients on normal diets; no abnormal amounts of beta-carotene had accumulated in the livers after oral administration of large amounts of beta-carotene. Light-microscopic examination of the liver (specimen obtained at c...

*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...

Colour is one of the most important visual attributes of food and is directly related to the perception of food quality. The interest in natural colourants, especially β-carotene that not only imparts colour but also has well-documented health benefits, has triggered the research and development of different protocols designed to entrap these hydrophobic natural molecules to improve their stabi...

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...

In 1981 it was hypothesized that a high dietary intake of n-carotene might reduce human cancer rates. Since then, several observational epidemiologic studies have addressed this topic. The results of both case-control and cohort studies show a remarkable consistency for the association of increased lung cancer risk with low amounts of dietary 3-carotene or low plasma /3-carotene concentrations....

Winter squash "type butternut" is harvested in physiological ripening for better commercial distribution, when sensory and/or nutritional quality is not optimum for consumption. The objective of this study was to quantify the content of α-carotene, β-carotene, color and dry matter in the pulp of raw and microwave-cooked winter squash "type butternut" (variety CosmoF1) in three states of commerc...

I T HAS been widely reported in the literature that carotene from different sources varies in its biological value (Ward, i94o; Fraps and Meinke, Rubin and Bird, t94i; Smith and Otis, i94i; Jones et al. I944). Since much of this work has been done with cattle, poultry, and small laboratory animals it has little direct application to sheep nutrition. If the efficiency of utilization of carotene ...

conclusions light and temperature were both relevant factors that contributed to the growth and beta-carotene accumulation of the three d. salina strains, and nahco3 had significantly positive effects on growth. the degree of impact of the different factors on cell growth was temperature > nahco3 > light intensity > kno3 > co (nh2)2 > strains; the impact on beta-carotene accumulation was temper...