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Letteratura scientifica selezionata sul tema "Carotenoids"

Autore: Grafiati

Pubblicato: 4 giugno 2021

Ultima modifica: 30 luglio 2024

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Articoli di riviste sul tema "Carotenoids"

Mahler, Bettina, Lidia S. Araujo e Pablo L. Tubaro. "Dietary and Sexual Correlates of Carotenoid Pigment Expression in Dove Plumage". Condor 105, n. 2 (1 maggio 2003): 258–67. http://dx.doi.org/10.1093/condor/105.2.258.

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Abstract Carotenoid pigmentation in birds' plumage is considered an honest indicator of phenotypic quality, and thus a target of sexual selection. But carotenoids also fulfill essential physiological functions, and therefore, carotenoids should only appear in plumage if they are in excess of those needed physiologically. We explored the presence of carotenoid-based plumage coloration in columbids and its association with diet and sexual dichromatism using a comparative analysis. We found that carotenoid plumage pigmentation appeared three times independently in doves, and that these events were always associated with frugivorous feeding habits. This suggests that expression of carotenoid-based plumage color in granivorous species may be constrained by the scarcity of carotenoids in their diet. However, more than half of the frugivorous species lack carotenoid-pigmented plumage, indicating that rich dietary sources of these compounds are a necessary but not sufficient cause for their expression in plumage. Analyzing 12 pairs of sister taxa, we found that plumage dichromatism was neither associated with the amount of carotenoid pigment present in the plumage nor with the sexual dimorphism in carotenoid-pigmented plumage. Although the presence of carotenoid-based plumage coloration has been related to sexual selection in several taxa, we failed to show such an association in columbids. Correlación de la Expresión de Pigmentos Carotenoides en el Plumaje de Palomas con la Dieta y la Selección Sexual Resumen. Los pigmentos carotenoides en el plumaje de las aves son considerados indicadores honestos de la calidad fenotípica y, por lo tanto, objetos de selección sexual. Sin embargo, los carotenoides también cumplen funciones fisiológicas esenciales, por lo cual aquellos que se expresan en el plumaje deberían estar en exceso de los utilizados a nivel fisiológico. Exploramos la presencia de carotenoides en el plumaje de las palomas y su asociación con la dieta y el dicromatismo sexual usando un análisis comparativo. Encontramos que el plumaje carotenoide apareció tres veces independientemente en palomas, y que estos eventos estaban siempre asociados a frugivoría. Esto sugiere que la expresión de carotenoides en el plumaje de especies granívoras puede estar restringida por la escasez de estos pigmentos en la dieta. Sin embargo, más de la mitad de las especies frugívoras carecen de plumaje carotenoide, indicando que alimentos ricos en este compuesto son una causa necesaria pero no suficiente para su expresión en el plumaje. Analizando 12 pares de taxa hermanos, encontramos que el dicromatismo no estaba asociado ni a la cantidad de pigmentos carotenoides presentes en el plumaje ni al dimorfismo sexual de plumaje carotenoide. Aunque la presencia de plumaje carotenoide ha sido relacionada con la selección sexual en numerosos grupos, no encontramos una asociación similar en palomas.

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McGraw, Kevin J., Geoffrey E. Hill e Robert S. Parker. "Carotenoid Pigments in a Mutant Cardinal: Implications for the Genetic and Enzymatic Control Mechanisms of Carotenoid Metabolism in Birds". Condor 105, n. 3 (1 agosto 2003): 587–92. http://dx.doi.org/10.1093/condor/105.3.587.

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Abstract Birds that use carotenoids to color their feathers must ultimately obtain these pigments from the diet, but they are also capable of metabolically transforming dietary carotenoids into alternate forms that they use as plumage colorants. The genetic and enzymatic control mechanisms underlying carotenoid metabolism are poorly understood. We investigated carotenoid pigments present in the feathers of an aberrantly colored yellow Northern Cardinal (Cardinalis cardinalis) to determine how metabolic pathways may have been altered. Normal red cardinals display four primary keto-carotenoids in plumage that are endogenously derived from a series of common food carotenoids. We found that the yellow feathers of this mutant lacked all four of the typical red pigments, and instead contained a yellow dietary carotenoid (lutein) and three yellow metabolic derivatives (3′-dehydrolutein and canary-xanthophylls A and B). Because yellow metabolites appear to be manufactured via a different metabolic process (dehydrogenation) than the usual red forms (oxidation at the C-4 or -4′ positions), it seems that this genetic mutation did not broadly disrupt all metabolic activity, but specifically impaired only one class of metabolic reactions and its associated enzymes. Pigmentos Carotenoides en un Cardenal Mutante: Implicaciones para los Mecanismos Genéticos y Enzimáticos de Control del Metabolismo de Carotenoides en las Aves Resumen. Las aves que utilizan pigmentos carotenoides para dar color a sus plumas deben obtenerlos de la dieta, pero también son capaces de transformar metabólicamente los carotenoides dietarios en formas alternativas que utilizan para colorear las plumas. Los mecanismos genéticos y enzimáticos de control involucrados en el metabolismo de los carotenoides no han sido bien establecidos. En este estudio investigamos los pigmentos carotenoides presentes en las plumas de un cardenal Cardinalis cardinalis con coloración amarilla aberrante para determinar cómo se podrían haber alterado las rutas metabólicas. Los cardenales normales de color rojo despliegan cuatro keto-carotenoides primarios en el plumaje, los cuales son derivados endógenamente a partir de una serie de carotenoides comunes en la dieta. Encontramos que las plumas amarillas del mutante carecían de los cuatro pigmentos rojos típicos, y contenían en cambio un carotenoide dietario amarillo (luteína) y tres derivados metabólicos amarillos (3′-dehidro luteína y xantofilas de canario A y B). Debido a que los metabolitos amarillos parecen ser fabricados mediante un proceso metabólico diferente al de las formas rojas usuales (deshidrogenación y oxidación en las posiciones C-4 o -4′, respectivamente), parece que esta mutación genética no alteró ampliamente toda la actividad metabólica. En cambio, parece haber inhabilitado sólo una clase de reacciones metabólicas y sus enzimas asociadas.

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Zurak, Dora, Darko Grbeša, Marija Duvnjak, Goran Kiš, Tatjana Međimurec e Kristina Kljak. "Carotenoid Content and Bioaccessibility in Commercial Maize Hybrids". Agriculture 11, n. 7 (24 giugno 2021): 586. http://dx.doi.org/10.3390/agriculture11070586.

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The objective of the present study was to determine the content and bioaccessibility of carotenoids in 104 maize hybrids available at the market. Lutein, zeaxanthin, α- and β-cryptoxanthin, and β-carotene were determined in whole grains and micelles produced during standardized INFOGEST digestibility analysis, and their bioaccessibility was calculated as the ratio of micellar and grain carotenoids. Tested hybrids varied in total carotenoid content, with 34% having total carotenoid content in the range of 15–20 µg/g dry matter (DM) and 41% in the range of 20–25 µg/g DM. The amount of bioaccessible carotenoids increased linearly (p < 0.05) with increasing content in the grain, and decreased among determined carotenoidsd in the order: lutein (52%) > zeaxanthin (43%) > β-carotene (43%) > α-cryptoxanthin (27%) > β-cryptoxanthin (26%). Bioaccessibility of lutein, zeaxanthin, and β-carotene decreased with increasing content in the grain (p < 0.05). On average, only 43% of the total carotenoids were bioaccessible in commercial maize hybrids tested, which should be considered when formulating an animal diet.

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Chedea, Veronica Sanda, Adela Pintea, Andrea Bunea, Cornelia Braicu, Andreea Stanila e Carmen Socaciu. "Physalis alkekengiCarotenoidic Extract Inhibitor of Soybean Lipoxygenase-1 Activity". BioMed Research International 2014 (2014): 1–7. http://dx.doi.org/10.1155/2014/589168.

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The aim of this study was to evaluate the effect of the carotenoidic saponified extract ofPhysalis alkekengisepals (PA) towards the lipoxygenase (LOX) oxidation of linoleic acid. Lipoxygenase activity in the presence of carotenoids, standard and from extract, was followed by its kinetic behaviour determining the changes in absorption at 234 nm. The standard carotenoids used wereβ-carotene (β-car), lutein (Lut), and zeaxanthin (Zea). The calculated enzymatic specific activity (ESA) after 600 s of reaction proves that PA carotenoidic extract has inhibitory effect on LOX oxidation of linoleic acid. A longer polyenic chain of carotenoid structure gives a higher ESA during the first reaction seconds. This situation is not available after 600 s of reaction and may be due to a destruction of this structure by cooxidation of carotenoids, besides the classical LOX reaction. The PA carotenoidic extract inhibiting the LOX-1 reaction can be considered a source of lipoxygenase inhibitors.

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McGraw, Kevin J., e Kirk C. Klasing. "Carotenoids, Immunity, and Integumentary Coloration in Red Junglefowl (Gallus Gallus)". Auk 123, n. 4 (1 ottobre 2006): 1161–71. http://dx.doi.org/10.1093/auk/123.4.1161.

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Abstract There is widespread interest in the roles that carotenoids play as yolk and shank pigments, antioxidants, and immune-system regulators in chickens, but nothing is known of such functions in the wild ancestors of chickens—the Red Junglefowl (Gallus gallus). We manipulated carotenoid access in the diet of captive male and female Red Junglefowl to investigate its effects on the coloration of the red comb and buff-brown legs and beak as well as on several indices of immunocompetence. Comb, leg, and beak did not differ in coloration between control and carotenoid-supplemented groups; in fact, biochemical analyses showed that, unlike in chickens, leg and beak tissue contained no carotenoids. Carotenoids showed variable effects on immunological performance, boosting the potency of whole blood in males to kill bacterial colonies, while inhibiting the ability of macrophages to phagocytize bacterial cells and having no significant effect on the accumulation of haptoglobin—an acute-phase protein whose production was induced by a simulated infectious challenge with lipopolysaccharide. These results bring into question interpretations of the evolutionary significance of carotenoid-based and sexually dichromatic shank coloration in domestic chickens, which was apparently derived through artificial selection, and suggest that carotenoids can exert different, mechanism-specific actions on the many lines of immune defense in birds. Carotenoides, Inmunidad y Coloración Integumentaria en Gallus gallus

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McGraw, Kevin J., Kazumasa Wakamatsu, Shosuke Ito, Paul M. Nolan, Pierre Jouventin, F. Stephen Dobson, Richard E. Austic et al. "You Can't Judge a Pigment by its Color: Carotenoid and Melanin Content of Yellow and Brown Feathers in Swallows, Bluebirds, Penguins, and Domestic Chickens". Condor 106, n. 2 (1 maggio 2004): 390–95. http://dx.doi.org/10.1093/condor/106.2.390.

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Abstract The two main pigment types in bird feathers are the red, orange, and yellow carotenoids and the black, gray, and brown melanins. Reports conflict, however, regarding the potential for melanins to produce yellow colors or for carotenoids to produce brown plumages. We used high-performance liquid chromatography to analyze carotenoids and melanins present in the yellow and brown feathers of five avian species: Eastern Bluebirds (Sialia sialis), Barn Swallows (Hirundo rustica), King Penguins (Aptenodytes patagonicus), Macaroni Penguins (Eudyptes chrysolophus), and neonatal chickens (Gallus domesticus). In none of these species did we detect carotenoid pigments in feathers. Although carotenoids are reportedly contained in the ventral plumage of European Barn Swallows (Hirundo rustica rustica), we instead found high concentrations of both eumelanins and phaeomelanins in North American Barn Swallows (H. r. erythrogaster). We believe we have detected a new form of plumage pigment that gives penguin and domestic- chick feathers their yellow appearance. No Puedes Juzgar un Pigmento por su Color: Contenido de Carotenoide y Melanina de Plumas Amarillas y Marrones en Golondrinas, Azulejos, Pingüinos y Gallinas Domésticas Resumen. Los dos tipos principales de pigmentos que las aves incorporan en sus plumas son carotenoides, para desarrollar plumajes rojo, naranja o amarillo, y melaninas, para adquirir coloración negra, marrón, gris o tonalidades color tierra. Sin embargo, existe información conflictiva sobre la potencial coloración de plumas amarillas basadas en melanina y la presencia de caroteniodes en el plumaje marrón de ciertas especies. En este estudio, usamos cromatografía líquida de alto rendimiento para analizar los tipos y cantidades de carotenoides y melaninas presentes en las plumas amarillas y marrones de cinco especies de aves: el azulejo Sialia sialis y la golondrina Hirundo rustica, los pingüinos Aptenodytes patagonicus y Eudyptes chrysolophus y el plumón natal amarillo de la gallina doméstica Gallus domesticus. En ninguna de estas especies detectamos pigmentos carotenoides en las plumas. A pesar de que los carotenoides han sido encontrados en el plumaje ventral de la golondrina Hirundo rustica rustica, nosotros en cambio encontramos altas concentraciones de eumelaninas y feomelaninas en H. r. erythrogaster y en azulejos que variaron entre individuos y regiones de plumaje. Creemos que hemos detectado una nueva forma de pigmento de plumaje que le da a las plumas de pingüinos y pollos domésticos su apariencia amarilla.

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Shilpa, P., K. V. Ravishankar, K. S. Shivashankara, A. T. Sadashiva e N. Sunil Kumar. "Molecular Mechanisms Involved in Biosynthesis and Regulation of Carotenoids in Plants". Journal of Horticultural Sciences 11, n. 2 (31 dicembre 2016): 91–103. http://dx.doi.org/10.24154/jhs.v11i2.78.

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Carotenoids are coloured compounds beneficial to plants and humans. Some of the major health benefits carotenoids provide include Vitamin A precursors and, antioxidants besides being involved in several physiological functions. Even though several carotenoids are synthesised by plants, only a few like beta/ alpha carotenes and cryptoxanthin serve as Vitamin A precursors. The rest are useful as antioxidants. To draw maximum benefits from carotenoids, we need to incorporate these in crop improvement programmes for enhancing available Vitamin A precursor carotenoids. Therefore, it is essential to study biosynthesis of carotenoids, their genetics and their control. In this review, we focus on factors regulating carotenoid biosynthesis, metabolism and storage in plastids. Transcriptional and genetic control of carotenoid production in plants is discussed in the review using several mutants too. Further, environmental regulation of carotenoid biosynthesis is also highlighted. Carotenoid-rich fruits and vegetables have greater economic value owing to their health-promoting effects. Besides,carotenoids have several industrial applications. Therefore, knowledge of regulation mechanism in carotenoid production in plants can help develop crop varieties or technologies, thus generating carotene-rich fruits and vegetables.

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Conboy Stephenson, Ruth, R. Paul Ross e Catherine Stanton. "Carotenoids in Milk and the Potential for Dairy Based Functional Foods". Foods 10, n. 6 (2 giugno 2021): 1263. http://dx.doi.org/10.3390/foods10061263.

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Carotenoids are a family of over 1100 known natural pigments synthesized by plants, algae, fungi and bacteria. Dietary intake of carotenoids is necessary for mammals as they cannot be synthesized in the body. In cows, the nature of the diet consumed strongly influences the composition of milk produced and this includes carotenoid concentration and profile. Fresh forage is the richest source of carotenoids for cows. The main carotenoids identified in forages are lutein, β-carotene, zeaxanthin and epilutein. Manipulating cow feed via carotenoid supplementation increases the carotenoid content of bovine milk. In humans, carotenoids have anti-oxidant, anti-inflammatory and provitamin A activity. Lutein is a major carotenoid in human milk and the brain tissue of adults and infants. Lutein and zeaxanthin are linked to improved eye health and cognitive function. Traditionally for humans, fruit and vegetables have been the main source of carotenoid intake. Functional foods present an opportunity to incorporate these naturally occurring compounds into milk products for added health benefits, widening the range of dietary sources of carotenoids. We offer an overview of the literature to date on carotenoid-fortified dairy products and infant formula. This review will describe and summarize the key mechanisms by which the carotenoid profile of bovine milk can be manipulated. We present findings on the origin and role of carotenoids in bovine and human milk, outline factors that impact the carotenoid content of milk, evaluate carotenoid-fortified milk products and discuss the associated challenges, such as bioaccessibility and stability.

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Metibemu, Damilohun Samuel, e Ifedayo Victor Ogungbe. "Carotenoids in Drug Discovery and Medicine: Pathways and Molecular Targets Implicated in Human Diseases". Molecules 27, n. 18 (15 settembre 2022): 6005. http://dx.doi.org/10.3390/molecules27186005.

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Carotenoids are isoprenoid-derived natural products produced in plants, algae, fungi, and photosynthetic bacteria. Most animals cannot synthesize carotenoids because the biosynthetic machinery to create carotenoids de novo is absent in animals, except arthropods. Carotenoids are biosynthesized from two C20 geranylgeranyl pyrophosphate (GGPP) molecules made from isopentenyl pyrophosphate (IPP) and dimethylallyl pyrophosphate (DMAPP) via the methylerythritol 4-phosphate (MEP) route. Carotenoids can be extracted by a variety of methods, including maceration, Soxhlet extraction, supercritical fluid extraction (SFE), microwave-assisted extraction (MAE), accelerated solvent extraction (ASE), ultrasound-assisted extraction (UAE), pulsed electric field (PEF)-assisted extraction, and enzyme-assisted extraction (EAE). Carotenoids have been reported to exert various biochemical actions, including the inhibition of the Akt/mTOR, Bcl-2, SAPK/JNK, JAK/STAT, MAPK, Nrf2/Keap1, and NF-κB signaling pathways and the ability to increase cholesterol efflux to HDL. Carotenoids are absorbed in the intestine. A handful of carotenoids and carotenoid-based compounds are in clinical trials, while some are currently used as medicines. The application of metabolic engineering techniques for carotenoid production, whole-genome sequencing, and the use of plants as cell factories to produce specialty carotenoids presents a promising future for carotenoid research. In this review, we discussed the biosynthesis and extraction of carotenoids, the roles of carotenoids in human health, the metabolism of carotenoids, and carotenoids as a source of drugs and supplements.

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Ngginak, James, Jubhar C. Mangibulude e Ferdy S. Rondonuwu. "The Identification of Carotenoids and Testing of Carotenoid Antioxidants from Sand Lobster (Panulirus homarus) Egg Extract". ILMU KELAUTAN: Indonesian Journal of Marine Sciences 22, n. 3 (22 agosto 2017): 155. http://dx.doi.org/10.14710/ik.ijms.22.3.155-160.

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Sand lobsters (Panulirus homarus) are organisms that play an important role in supporting a society’s economy. Lobsters have a business appeal due to their high demand, enjoyable taste, as well as significant nutritional content. It is interesting that sand lobster eggs have a yellow orange color as an indicator of the presence of carotenoid content. Related with advancements in research and the utilization of carotenoids, this research identifies carotenoids and tests carotenoid antioxidants from sand lobster (Panulirus homarus) egg extract. In identifying carotenoids in sand lobster egg extract, HPLC (high performance liquid chromatography) (shimadzu LC-10AD, Japan) is used. In testing carotenoid antioxidants from sand lobster eggs, a DPPH method is utilized. The identification results with HPLC reveal that the sample contains carotenoids. The kinds of carotenoids identified are dinoxanthin, diadinoxanthin, zeaxanthin, lutein, astaxanthin, and violaxanthin. Among the six kinds of carotenoids identified, lutein is the type of carotenoid that has the highest concentration. These carotenoid compounds are detected in wavelengths of 400-500 nm. The test results of antioxidant power reveal that to hamper free radicals (IC50), a sample concentration of 6675.25 µg.ml-1 is needed. The ability to hinder free radicals from a sample extract is mostly conducted by lutein, zeaxanthin, and astaxantin. If seen from the analytical results, it can be surmised that sand lobster eggs contain carotenoids that can be used as a carotenoid source for humans. Keywords : Sand Lobster, HPLC, Carotenoids, DPPH, Antioxidant

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Più fonti

Tesi sul tema "Carotenoids"

Tawata, Natalia. "Determinação de carotenoides em alimentos brasileiros in natura, processados e preparados para a tabela nacional de composição de alimentos". [s.n.], 2010. http://repositorio.unicamp.br/jspui/handle/REPOSIP/256123.

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Orientador: Delia B. Rodriguez-Amaya
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
Made available in DSpace on 2018-08-15T02:59:46Z (GMT). No. of bitstreams: 1 Tawata_Natalia_M.pdf: 1734713 bytes, checksum: c645e7426f02ffd742fed5ec2def16c3 (MD5) Previous issue date: 2010
Resumo: A biodiversidade brasileira em fontes de carotenóides foi demonstrada no Capítulo 1, focalizando a riqueza dos alimentos brasileiros nativos ou pouco cultivados nos seis carotenóides (alfa-caroteno, B-caroteno, B-criptoxantina, licopeno, luteína e zeaxantina) considerados importantes à saúde. No Capítulo 2, dentre os produtos in natura analisados, frutas de clima temperado apresentaram menores teores de carotenóides do que as frutas tropicais, sendo a manga ¿Palmer¿ a maior fonte de -caroteno. Vegetais folhosos altamente consumidos como alface roxa e rúcula são ricos em luteína e -caroteno. Banana e tangerina são frutas comumente consumidas que apresentaram teores apreciáveis de carotenóides. No Capítulo 3, foi observado que a composição qualitativa de carotenóides em alimentos processados e preparados reflete a matéria-prima utilizada e a degradação de carotenóides. Entre os alimentos processados e preparados analisados, somente a goiabada em pasta apresentou licopeno com teor altíssimo. A seleta de legumes possui o maior teor de -caroteno. O teor de B-criptoxantina foi maior em pêssego enlatado. O cereal de milho com açúcar apresentou como carotenóide majoritário a zeaxantina. Os maiores teores de B-caroteno e luteína foram encontrados na catalonha e espinafre refogados. A comparação entre os dados obtidos por análise direta do alimento preparado e por cálculo utilizando dados tabelados dos ingredientes revelaram diferenças marcantes para as três receitas investigadas
Abstract: Brazilian biodiversity in sources of carotenoids is demonstrated in Chapter 1, higlighting the richness of native and uncultivated Brazilian foods in the six carotenoids (alpha-carotene, B-carotene, B-cryptoxanthin, lycopene, lutein and zeaxanthin) considered important to human health. In Chapter 2, among the raw foods analyzed, fruits of temperate climates had lower levels of carotenoids than tropical fruits, the mango ¿Palmer¿ being the major source of -carotene. Highly consumed leafy vegetables such as purple lettuce and roquette are rich in lutein and B-carotene. Banana and tangerine are commonly consumed fruits that present appreciable amounts of carotenoids. In Chapter 3, it was observed that the qualitative composition reflected the raw material used and degradation of carotenoids. Among the processed and prepared foods analyzed, only ¿goiabada¿ had lycopene at high level. A mixture of vegetables had the highest concentration of B-carotene. B-cryptoxanthin was higher in canned peach. Cereal with sugar presented zeaxanthin as the principal carotenoid. The highest levels of -carotene and lutein were found in stir-fried ¿catalonha¿ and New Zealand spinach. A comparison between calculated values and those obtained by direct analysis of three prepared foods revealed marked differences
Mestrado
Mestre em Ciência de Alimentos

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Foster, Linda Ann. "Intracellular Location of Carotenoid Pigments in Yeast-Phase Cells of Wangiella Dermatitidis and Cell Wall Morphology After Enzyme Treatment". Thesis, University of North Texas, 1991. https://digital.library.unt.edu/ark:/67531/metadc798104/.

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Carotenoid pigments in W. dermatitidis, the first pathogenic, dematiaceous fungus in which carotenoid pigments nave been reported, are located primarily (81%) in lipid organelles which floated on the surface of the supernatant fraction of lysed cells. Pigment in this fraction could be extracted with ethyl ether without prior treatment with acetone indicating the pigment is unbound in the lipid organelle. Eight percent remains after exhaustive ether extraction and is recovered after the sample is treated with acetone indicating this fraction is non-covalently bound to proteins in the membranes associated with the lipid organelle. The remaining pigment (about 12%) represents contamination of the supernatant with the lipid organelles.

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Conn, Pauline Frances. "Photophysical chemistry of carotenoids". Thesis, Keele University, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.315187.

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Tsavalos, Alexander John. "Production of microalgal secondary carotenoids". Thesis, Liverpool John Moores University, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.337891.

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Thakkar, Sagar. "PRE-ABSORPTIVE METABOLISM OF CAROTENOIDS". The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1244048450.

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Koutsos, Elizabeth Allison. "Carotenoids in avian immune systems /". For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2002. http://uclibs.org/PID/11984.

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Cobb, Bonnie Finn. "Extracting Carotenoids from Corn Industry Coproducts". Thesis, North Dakota State University, 2016. https://hdl.handle.net/10365/28243.

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Two experiments were completed to develop methods for extracting xanthophylls from corn industry co-products, post fermentation (PF) corn oil and corn gluten meal (CGM). A solid phase extraction (SPE) method was used to fractionate a xanthophyll-rich portion of PF corn oil by varying conditioning and eluting solvents used with a diol SPE column. Conditioning with dichloromethane yielded highest xanthophyll fractionation, 86.5%. The elution solvent selected did not impact fractionation based on a two-way ANOVA. Supercritical fluid extraction of xanthohpylls from CGM was modeled using a Box-Behnken design, varying temperature, pressure, and co-solvent ratio. The optimum conditions were determined to be 40 ?C, 6820 psi, and 15% co-solvent, which would extract 85.4 ?g lutein/g CGM, 2.6 times more lutein than an ethanol and chloroform: dichloromethane solvent extraction. Co-solvent was the most influential extraction parameter and increasing it further could yield higher xanthophyll recovery. With further studies, this work has industrial potential.
Golden Growers; North Dakota Corn Council

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Figueiredo, Bruna Flávia Henriques Tavares. "Carotenoids extraction from the microalga Phaeodactylum tricornutum". Master's thesis, Universidade de Aveiro, 2015. http://hdl.handle.net/10773/19136.

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Mestrado em Biotecnologia, ramo de Biotecnologia Industrial e Ambiental
Microalgae have been attracting a crescent attention regarding either the potential use of their biomass or the wide range of compounds of interest that they have in their constitution, which can be extracted and applied in several fields of industry, namely carotenoids and in particular fucoxanthin.. Fucoxanthin is a photosynthetic pigment, with numerous applications and benefits, namely in the human healthrelated domains, due to its high antioxidant properties, essential in the prevention and treatment of several diseases, such as cancer and cardiovascular diseases. Hereupon, the development of a feasible route for the production of carotenoids rich in fucoxanthin which could allow its commercialization is of utmost scientific, industrial and even social relevance. The Phaeodactylum tricornutum species is being reported as a relevant producer of fucoxanthin. Still, there are no economic feasible extraction methods for the carotenoids, and in particular fucoxanthin, considering their efficient obtainment with high purity levels. Thus, this work is aiming at the development of a sustainable and feasible production and extraction platform for the extraction of carotenoids (and fucoxanthin) from Phaeodactylum tricornutum. In this sense, a conventional methodology was optimized, as well as a novel extraction methodology based on alternative tensioactive solvents, exclusively in aqueous solution, namely common surfactants, copolymers and tensioactive ionic liquids. Regarding the alternative method developed, it was possible to achieve a final extraction of 32.67 mgcarotenoids/gbiomass with the ionic liquid [C18mim]Cl and 10.69 mgfucoxanthin/gbiomass with [C14mim]Cl, similar values or even superior when compared with those found for the conventional methodology. At the end, the achievement of fucoxanthin in its purest form is foreseen for further industrial application.
As microalgas têm vindo a despertar cada vez mais interesse pelas potencialidades de utilização da biomassa como um todo, quer pela diversidade de compostos de interesse que as constituem, com aplicações variadas, como é o caso dos carotenóides e, em particular, da fucoxantina. Fucoxantina é um pigmento fotossintético com inúmeras aplicações e benefícios, nomeadamente na área da saúde, pelasua elevada atividade antioxidante, importante na prevenção e tratamento de várias doenças, como o cancro e doenças cardiovasculares. Desta forma, é de interesse científico, industrial e mesmo social, o desenvolvimento de uma plataforma economicamente eficiente de produção e extração destes carotenóides que permitam o seu uso em larga escala, visando assim a sua aplicação industrial. Existem diversos estudos que apontam as microalgas como grandes produtoras deste pigmento, nomeadamente a espécie Phaeodactylum tricornutum. No entanto, os métodos de extração e purificação de carotenóides e em particular de fucoxantina que permitam a recuperação destes compostos com elevado grau de pureza são ainda algo deficitários, no que diz respeito ao seu elevado impacto económico e ambiental. Assim, o objetivo deste trabalho recai no desenvolvimento de uma plataforma rentável para produção e extração de carotenóides (e fucoxantina) a partir da microalga Phaeodactylum tricornutum. Para tal, o método de extração convencional foi otimizado, assim como foi desenvolvido um método de extração alternativo recorrendo ao uso de solventes alternativos com natureza tensioativa exclusivamente em solução aquosa, nomeadamente surfactantes comuns, copolímeros e líquidos iónicos tensioativos. A partir deste método alternativo foi possível extrair um total de 32.67 mgcarotenoides/gbiomassa com o [C18mim]Cl e 10.69 mgfucoxantina/gbiomassa com [C14mim]Cl, valores semelhantes ou mesmo superiores aos obtidos pelo método convencional.

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Lian, Fuzhi. "The anti-carcinogenic effect of carotenoids against lung cancer /". Thesis, Connect to Dissertations & Theses @ Tufts University, 2006.

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Thesis (Ph.D.)--Tufts University, 2006.
Submitted to the School of Nutrition Science and Policy. Adviser: Xiang-Dong Wang. Includes bibliographical references. Access restricted to members of the Tufts University community. Also available via the World Wide Web;

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Kopec, Rachel Elizabeth. "Bioavalability, Metabolism, and Bioefficacy of Tomato Carotenoids". The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1354735735.

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Libri sul tema "Carotenoids"

Britton, George, Synnøve Liaaen-Jensen e Hanspeter Pfander, a cura di. Carotenoids. Basel: Birkhäuser Basel, 2004. http://dx.doi.org/10.1007/978-3-0348-7836-4.

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Krinsky, Norman I., Micheline M. Mathews-Roth e Richard F. Taylor, a cura di. Carotenoids. Boston, MA: Springer US, 1989. http://dx.doi.org/10.1007/978-1-4613-0849-2.

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Britton, George, Synnøve Liaaen-Jensen e Hanspete Pfander, a cura di. Carotenoids. Basel: Birkhäuser Basel, 2008. http://dx.doi.org/10.1007/978-3-7643-7499-0.

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Britton, George, Hanspeter Pfander e Synnøve Liaaen-Jensen, a cura di. Carotenoids. Basel: Birkhäuser Basel, 2009. http://dx.doi.org/10.1007/978-3-7643-7501-0.

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Britton, George, Synnøve Liaaen-Jensen e Hanspeter Pfander, a cura di. Carotenoids. Basel: Birkhäuser Basel, 1996. http://dx.doi.org/10.1007/978-3-0348-9323-7.

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Kaczor, Agnieszka, e Malgorzata Baranska, a cura di. Carotenoids. Chichester, UK: John Wiley & Sons, Ltd, 2016. http://dx.doi.org/10.1002/9781118622223.

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Lester, Packer, a cura di. Carotenoids. San Diego: Academic Press, 1992.

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George, Britton, a cura di. Carotenoids. Basel: Birkhäuser Verlag, 1996.

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George, Britton, Liaaen-Jensen S. 1932- e Pfander H. 1940-, a cura di. Carotenoids. Basel: Birkhäuser Verlag, 1995.

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Barreiro, Carlos, e José-Luis Barredo, a cura di. Microbial Carotenoids. New York, NY: Springer New York, 2018. http://dx.doi.org/10.1007/978-1-4939-8742-9.

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Capitoli di libri sul tema "Carotenoids"

Liaaen-Jensen, Synnøve. "Artifacts of Natural Carotenoids — Unintended Carotenoid Synthesis". In Carotenoids, 149–65. Boston, MA: Springer US, 1989. http://dx.doi.org/10.1007/978-1-4613-0849-2_9.

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Kaczor, Agnieszka, Malgorzata Baranska e Krzysztof Czamara. "Carotenoids". In Carotenoids, 1–13. Chichester, UK: John Wiley & Sons, Ltd, 2016. http://dx.doi.org/10.1002/9781118622223.ch1.

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Britton, George, Synnøve Liaaen-Jensen e Hanspeter Pfander. "Introduction and guidelines on the use of the Handbook". In Carotenoids, 1–33. Basel: Birkhäuser Basel, 2004. http://dx.doi.org/10.1007/978-3-0348-7836-4_1.

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Britton, George, Synnøve Liaaen-Jensen e Hanspeter Pfander. "Main List". In Carotenoids, 35–545. Basel: Birkhäuser Basel, 2004. http://dx.doi.org/10.1007/978-3-0348-7836-4_2.

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Britton, George, Synnøve Liaaen-Jensen e Hanspeter Pfander. "Supplementary List". In Carotenoids, 547–625. Basel: Birkhäuser Basel, 2004. http://dx.doi.org/10.1007/978-3-0348-7836-4_3.

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Pfander, Hanspeter, Synnøve Liaaen-Jensen e George Britton. "Synthesis in Perspective". In Carotenoids, 1–6. Basel: Birkhäuser Basel, 1996. http://dx.doi.org/10.1007/978-3-0348-9323-7_1.

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Pfander, Hanspeter, e Birgit Bartels. "Synthesis of Cyclic Carotenoids". In Carotenoids, 161–200. Basel: Birkhäuser Basel, 1996. http://dx.doi.org/10.1007/978-3-0348-9323-7_10.

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Ito, Masayoshi. "Synthesis of Acetylenic, Allenic and In-chain Substituted Carotenoids". In Carotenoids, 201–16. Basel: Birkhäuser Basel, 1996. http://dx.doi.org/10.1007/978-3-0348-9323-7_11.

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Bernhard, Kurt, e Synnøve Liaaen-Jensen. "Total Synthesis of (Z)-Isomers". In Carotenoids, 217–32. Basel: Birkhäuser Basel, 1996. http://dx.doi.org/10.1007/978-3-0348-9323-7_12.

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Jansen, Frans Jos, e Johan Lugtenburg. "Labelled Carotenoids". In Carotenoids, 233–58. Basel: Birkhäuser Basel, 1996. http://dx.doi.org/10.1007/978-3-0348-9323-7_13.

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Atti di convegni sul tema "Carotenoids"

Konrade, Daiga, e Kriss Spalvins. "Extraction of bioactives from pumpkin by-products and determination of their antioxidant activity". In Research for Rural Development 2022 : annual 28th international scientific conference proceedings. Latvia University of Life Sciences and Technologies, 2022. http://dx.doi.org/10.22616/rrd.28.2022.016.

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Agro-industrial and food processing from pumpkins (Cucurbitaceae) produces a large number of by-products: bark, pomace, seeds still rich in bioactive compounds, especially carotenoids and green pigments (proto chlorophyll (a and b) and proto pheophytin (a and b)), which exhibit a broad spectrum of health-promoting effects and can be used as ingredients in functional food and cosmetics. For extraction of bioactive compounds from dried pumpkin by-products different methods were used: supercritical CO2, Soxhlet extraction with n- hexane, ethanol. Vegetable oils (rapeseed, coconut, grapeseed and olive oil) were used as green solvent alternatives to conventional organic solvents for carotenoid extraction. Detection and analyses of chlorophylls and carotenoids was done with hexane/acetone, cyclohexane, ethanol as solvents. The aim of this study was to use pumpkin by-products for extraction of high-value bioactive compounds with different methods, to determine antioxidant´s content and profile – carotenoids (ß-carotene, lutein, lycopene, zeaxanthin), pigments (chlorophylls a, chlorophylls b) with different solvents and to find out what solvent can be used for detection of pigments and carotenoids; to determine antiradical scavenging activity of biologically active compounds in extracts from pumpkin by-products (peel and hulled seeds).

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Calinescu, Ioan, Alin Vintila, Aurel Diacon, Mircea Vinatoru, Ana Maria Galan e Sanda Velea. "GROWTH OF NANNOCHLORIS ALGAE IN THE PRESENCE OF MICROWAVES (CONTINUOUS REACTOR)". In Ampere 2019. Valencia: Universitat Politècnica de València, 2019. http://dx.doi.org/10.4995/ampere2019.2019.9820.

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Algae are very effective in capturing the sun's energy, carbon dioxide from the atmosphere, and nutrients to turn them into useful substances (carbohydrates, oils, proteins, etc.). Besides the main metabolites, there are also secondary metabolites, such as carotenoids (astaxanthin, β-carotene, lutein, lycopene, and canthaxanthin [1]). Both major and compounds existing in small amounts in algae are useful. Oils and carbohydrates could provide biofuels, proteins can get products with nutritional value and from carotenoids can be prepared food supplements. Obtaining biofuel from algae has not yet proved to be economically viable [2, 3]. A much higher interest might be getting food supplements from algae. To increase their value as ingredients for food supplements, algal oils should have a higher degree of unsaturation (rich in omega 3) and an increased carotenoid content to be an important additional benefit in over all processing of algae. There are studies that refer to the influence of environmental factors on algae composition [2], but the microwave influence on algae growth, especially algal metabolites composition change is very poor studied. In this paper, besides the experiments for the activation of algal growth in discontinuous reactors [4] additional work was conducted in a continuous photobioreactor. The goal was checking not only the growth of microalgae but also their content in polyunsaturated oil and in carotenoids. By microwave-controlled irradiation of the nutrient and algae flux, which is recirculated through the photobioreactor and through a glass reactor located in a TE-type monomod cavity, the lipid content of the algae increased, but only, the modification of the lipid fraction content was significantly increased in the concentration of polyunsaturated acids with 16 and 18 carbon atoms. As far as carotenoids are concerned, the algae nannochloris has a higher carotenoid content over many known vegetables holding carotene or lycopene (carrots or tomatoes). Besides oil increasing microwave treatment produced a significant increase in carotenoid content of algae. They can be extracted together with omega-3-rich algal oil and are the basis of very valuable dietary supplements.

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Summons, R., F. Husain, X. Cui, S. Rohret, X. Liu, P. Welander, G. Shen e D. Bryant. "Cyanobacterial Aromatic Carotenoids". In 30th International Meeting on Organic Geochemistry (IMOG 2021). European Association of Geoscientists & Engineers, 2021. http://dx.doi.org/10.3997/2214-4609.202134084.

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Clark, Kameron A. "Effects of dietary carotenoids on carotenoid sequestration and immune response inTrichoplusia ni". In 2016 International Congress of Entomology. Entomological Society of America, 2016. http://dx.doi.org/10.1603/ice.2016.115011.

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Britton, G. "What's Special about Carotenoids?" In 13th World Congress of Food Science & Technology. Les Ulis, France: EDP Sciences, 2006. http://dx.doi.org/10.1051/iufost:20060812.

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Davis, J. A., E. Cannon, L. V. Dao, P. Hannaford, K. A. Nugent e H. M. Quiney. "Coherent Effects in Carotenoids". In International Conference on Ultrafast Phenomena. Washington, D.C.: OSA, 2010. http://dx.doi.org/10.1364/up.2010.thb3.

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Drljača, Tamara, Kristina Stevanović, Draginja Radošević, Jelena Milićević, Nevena Veljković e Sanja Glišić. "In silico screening of Solanum lycopersicum carotenoids from Carotenoids Database for candidates PPARα agonists". In 2nd International Conference on Chemo and Bioinformatics. Institute for Information Technologies, University of Kragujevac, 2023. http://dx.doi.org/10.46793/iccbi23.605d.

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Peroxisome proliferator-activated receptor alpha (PPARα) is crucial in regulating lipid metabolism. Clinically, PPARα is significant as a possible therapeutic target for a variety of human disorders, including cardiovascular, neurological, and metabolic syndromes. The wide range of natural compounds provides great opportunities for new approaches in targeting PPARα. Carotenoids, a large class of natural compounds, have been recognized as PPARα agonists. Tomatoes (Solanum lycopersicum) are one of the most widely grown crops in the world and contain compounds that improve lipid metabolism. Since there is no data on tomato carotenoids as PPARα agonists in this study, we focused on searching carotenoids from tomatoes as possible PPARα agonists. The Solanum lycopersicum carotenoids from Carotenoids Database were in silico screened using a combined protocol with the Electron-Ion Interaction Potential/Average Quasi Valence Number (EIIP/AQVN) filter and molecular docking to find the most promising candidate compounds. The best resulting compounds may have the promise to be further developed as candidates for PPARα agonists.

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Kamaruddin, Amirah Hanani, Norashikin Ahmad Zamanhuri e Rafeqah Raslan. "Extraction Yield of Palm Oil and Carotenoids Value from Microwave-Sterilized Oil Palm Mesocarp". In International Conference on Nanoscience and Nanotechnology 2022. Switzerland: Trans Tech Publications Ltd, 2023. http://dx.doi.org/10.4028/p-c4h8lr.

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Steam batch sterilization is favorably utilized by conventional palm oil mills in Malaysia. However, there are some disadvantages to using steam batch sterilization, including the fact that it takes a long time to complete the sterilizing process, and a huge amount of wastewater is released as palm oil mill effluent (POME). Besides, extraction by fruit press expeller requires a large number of nuts or seeds to produce a high yield, which is relatively expensive. Therefore, this research aimed to investigate the capability of microwave sterilization and the Soxhlet extraction (solvent extraction) process as an alternative to the conventional method. The impact of various microwave power levels of 400, 600, and 800 W and water ratios of 0, 50, and 100 mL on oil yield and carotenoids value of microwave-sterilized oil palm mesocarp are also investigated. Microwave sterilization and Soxhlet extraction have been employed as a replacement for the conventional method of extracting a higher yield of palm oil mesocarp in order to fill the gap by the previous research, which applied two methods: microwave sterilization (power level) and extraction. Then, carotenoid value analysis with a UV spectrophotometer is utilized to examine the outcomes in order to demonstrate the efficacy of the method. As a result, a high oil yield and carotenoid value are produced, which is 59.31% at 800W with the absence of water (0 mL) and a carotenoid value of 757 ppm at 400W (0 mL), respectively. Meanwhile, other carotenoid values at different microwave power levels and water ratios are still within the acceptable range as per the commercial crude palm oil standard.

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Levy, J. "Bone health-supporting activity of carotenoids". In 13th World Congress of Food Science & Technology. Les Ulis, France: EDP Sciences, 2006. http://dx.doi.org/10.1051/iufost:20060829.

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Dufossé, Laurent. "Microbial carotenoids as bioactive food ingredients". In Foods: Bioactives, Processing, Quality and Nutrition. Basel, Switzerland: MDPI, 2013. http://dx.doi.org/10.3390/bpqn2013-01169.

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Rapporti di organizzazioni sul tema "Carotenoids"

Kispert, Lowell. Magnetic Resonance and Optical Spectroscopic Studies of Carotenoids. Office of Scientific and Technical Information (OSTI), maggio 2014. http://dx.doi.org/10.2172/1132066.

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Gantt, Elisabeth, Avigad Vonshak, Sammy Boussiba, Zvi Cohen e Amos Richmond. Carotenoid-Rich Algal Biomass for Aquaculture: Astaxanthin Production by Haematococcus Pluvialis. United States Department of Agriculture, agosto 1996. http://dx.doi.org/10.32747/1996.7613036.bard.

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The synthesis of carotenoids has been studied toward enhancing the production of ketocarotenoids, since fish and crustaceans raised by aquaculture require astaxanthin and other ketocaroteinoids in their feed for desirable pigmentation. Notable progress has been made in attaining the goals of determining improved conditions for ketocarotenoid production in Haematococcus pluvialis and in elucidating the carotenoid biosynthetic pathway. For production of astaxanthin a number of strains of the green alga Haematococcus were evaluated, a strain CCAG was found to be optimal for photoautotrophic growth. Of four mutants, selected for enhanced carotenoid production, two hold considerable promise because caroteinoid accumulation occurs without encystment. The biosynthetic pathway of carotenoids was elucidated in photosynthetic organisms by characterizing novel genes encoding carotenoid enzymes and by examining the function of these enzymes in a bacterial complementation system. Two cyclases (b- and e-) were cloned that are at a critical branch point in the pathway. One branch leads to the formation of b-carotene and zeaxanthin and astaxanthin, and the other to the production of a-carotene and lutein. Cyclization of both endgroups of lycopene to yield b-carotene was shown to be catalyzed by a single gene product, b-lycopene cyclase in cyanobacteria and plants. The formation of a-carotene was found to require the e-cyclase gene product in addition to the b-cyclase. By cloning a b-hydroxylase gene we showed that a single gene product forms zeaxanthin by hydroxylatin of both b-carotene rings. It is expected that a second hydroxylase is required in the synthesis of astaxanthin, since canthaxanthin rather than zeaxanthin is the precursor. Evidence, from inhibitor studies, suggests that astaxanthin is formed from canthaxanthin and that b-carotene is a major precursor. Feasibility studies with the photobioreactors have shown that a two-stage system is the most practical, where Haematococcus cultures are first grown to high cell density and are then switched to high light for maximal astaxanthin production. The basic knowledge and molecular tools generated from this study will significantly enhance Haematococcus as a viable model for enhanced astaxanthin production.

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Van Tassle, Aaron Justin. Excited State Structural Dynamics of Carotenoids and ChargeTransfer Systems. Office of Scientific and Technical Information (OSTI), gennaio 2006. http://dx.doi.org/10.2172/925609.

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Hirschberg, Joseph, e Gloria A. Moore. Molecular Analysis of Carotenoid Biosynthesis in Plants: Characterizing the Genes Psy, Pds and CrtL-e. United States Department of Agriculture, agosto 1993. http://dx.doi.org/10.32747/1993.7568744.bard.

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In this research we have studied the molecular biology of carotenoid biosynthesis in tomato. The investigations focused on the genes Pds and Psy, encoding desaturase and phytoene synthase, respectively, which are key enzymes in the biosynthetic pathway of lycopene and b-carotene. In addition, we have investigated the genes for lycopene cyclase. We have cloned from tomato and characterized the cDNA of CrtL-e, which encodes the lycopene e-cyclase, and analyzed its expression during fruit development. The results establish a paradigm for the regulation of carotenoid pigment biosynthesis during the ripening process of fruits. It is concluded that transcriptional regulation of genes that encode carotenoid-biosynthesis enzymes is the major mechanism that governs specific pigment accumulation. During the ripening of tomato fruits transcription of the genes encoding the enzymes phytoene synthase and phytoene desaturase is up-regulated, while the transcription of the genes for both lycopene cyclases decreases and thus the conversion of lycopene to subsequent carotenoids is inhibited. These findings support the working hypothesis of the molecular approach to manipulating carotenogenesis by altering gene expression in transgenic plants, and offer obvious strategies to future application in agriculture. The molecular and physiological knowledge on carotenogenesis gained in this project, suggest a concept for manipulating gene expression that will alter carotenoid composition in fruits and flowers.

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Shaw, John, Arieh Rosner, Thomas Pirone, Benjamin Raccah e Yehezkiel Antignus. The Role of Specific Viral Genes and Gene Products in Potyviral Pathogenicity, Host Range and Aphid Transmission. United States Department of Agriculture, agosto 1992. http://dx.doi.org/10.32747/1992.7561070.bard.

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Rocheford, Torbert, Yaakov Tadmor, Robert Lambert e Nurit Katzir. Molecular Marker Mapping of Genes Enhancing Tocol and Carotenoid Composition of Maize Grain. United States Department of Agriculture, dicembre 1995. http://dx.doi.org/10.32747/1995.7571352.bard.

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The overall objective of this research was to identify chromosomal regions and candidate genes associated with control of concentration and forms of carotenoids (includes pro-Vitamin A) and tocopherols (Vitamin E), which are both antioxidants and are associated with health advantages. Vitamin A and E are included in animal feeding supplements and the eventual goal is to increase levels of these compounds in maize grain so that the cost of these supplements can be reduced or eliminated. Moreover, both compounds are antioxidants that protect unsaturated fatty acids from oxidation and thus maintaining maize oil quality for longer periods. We identified three SSR markers that are associated with 38% of the variation for total carotenoids and three SSR markers associated with 44% of the variation for total tocopherols in the cross W64a x A632. We identified two candidate genes associated with levels of carotenoids: phytoene synthase and zeta carotene desaturase. Evaluation of (Illinois High Oil x B73) B73 BC 1S1 population for tocopherols detected additional chromosomal regions influencing the level of total tocopherols, and detected a common region on chromosome 5 associated with ratio of the more desirable alpha from to the gamma form of tocopherol. The results suggest molecular marker assisted selection for higher levels of these antioxidants in corn grain should be feasible.

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Li, Li, Joseph Burger, Nurit Katzir, Yaakov Tadmor, Ari Schaffer e Zhangjun Fei. Characterization of the Or regulatory network in melon for carotenoid biofortification in food crops. United States Department of Agriculture, aprile 2015. http://dx.doi.org/10.32747/2015.7594408.bard.

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The general goals of the BARD research grant US-4423-11 are to understand how Or regulates carotenoid accumulation and to reveal novel strategies for breeding agricultural crops with enhanced β-carotene level. The original objectives are: 1) to identify the genes and proteins in the Or regulatory network in melon; 2) to genetically and molecularly characterize the candidate genes; and 3) to define genetic and functional allelic variation of these genes in a representative germplasm collection of the C. melo species. Or was found by the US group to causes provitamin A accumulation in chromoplasts in cauliflower. Preliminary genetic study from the Israeli group revealed that the melon Or gene (CmOr) completely co-segregated with fruit flesh color in a segregating mapping population and in a wide melon germplasm collection, which set the stage for the funded research. Major conclusions and achievements include: 1). CmOris proved to be the gene that controls melon fruit flesh color and represents the previously described gflocus in melon. 2). Genetic and molecular analyses of CmOridentify and confirm a single SNP that is responsible for the orange and non-orange phenotypes in melon fruit. 3). Alteration of the evolutionarily conserved arginine in an OR protein to both histidine or alanine greatly enhances its ability to promote carotenoid accumulation. 4). OR promotes massive carotenoid accumulation due to its dual functions in regulating both chromoplast biogenesis and carotenoid biosynthesis. 5). A bulk segregant transcriptome (BSRseq) analysis identifies a list of genes associated with the CmOrregulatory network. 6). BSRseq is proved to be an effective approach for gene discovery. 7). Screening of an EMS mutation library identifies a low β mutant, which contains low level of carotenoids due to a mutation in CmOrto produce a truncated form of OR protein. 8). low β exhibits lower germination rate and slow growth under salt stress condition. 9). Postharvest storage of fruit enhances carotenoid accumulation, which is associated with chromoplast development. Our research uncovers the molecular mechanisms underlying the Or-regulated high level of carotenoid accumulation via regulating carotenoidbiosynthetic capacity and storage sink strength. The findings provide mechanistic insights into how carotenoid accumulation is controlled in plants. Our research also provides general and reliable molecular markers for melon-breeding programs to select orange varieties, and offers effective genetic tools for pro-vitamin A enrichment in other important crops via the rapidly developed genome editing technology. The newly discovered low β mutant could lead to a better understanding of the Or gene function and its association with stress response, which may explain the high conservation of the Or gene among various plant species.

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Levy, Arieh, Paul Bosland e Dan Palevitch. Determination of Carotenoids and Capsaicinoids in Chile Peppers and Paprika: Genetic, Physiological and Horticultural Apects. United States Department of Agriculture, marzo 1994. http://dx.doi.org/10.32747/1994.7603837.bard.

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Kispert, L. D. Magnetic resonance and optical spectroscopic studies of carotenoids. Progress report, December 1, 1991--November 30, 1994. Office of Scientific and Technical Information (OSTI), maggio 1994. http://dx.doi.org/10.2172/10196714.

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Kispert, L. D. Magnetic resonance and optical spectroscopic studies of carotenoids. Progress report, December 1, 1994--November 30, 1995. Office of Scientific and Technical Information (OSTI), giugno 1995. http://dx.doi.org/10.2172/179206.

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