Relevant bibliographies by topics / Provitamin A

Contents

  1. Journal articles
  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers
  6. Reports

Academic literature on the topic 'Provitamin A'

Author: Grafiati
Published: 4 June 2021
Last updated: 26 January 2023

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Provitamin A.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Journal articles on the topic "Provitamin A"

1

Mosuro, Aderonke, and Olugbenga Ogunwole. "Vitamin and provitamin profiles of selected vegetables as affected by storage and different drying methods." Journal of Agricultural Sciences, Belgrade 64, no. 2 (2019): 175–88. http://dx.doi.org/10.2298/jas1902175m.

Full text
Abstract:
Effects of drying methods on the vitamin and provitamin compositions of selected vegetables during storage were assessed in this study. Telfaria occidentalis, Celosia argentea (green), Vernonia amygdalina, Moringa oleifera, Launaea taraxacifolia, Curcubita maxima and Celosia argentea (red) were subjected to air drying (AD), oven drying (OD) and freeze drying (FD). The experiment was a 3x7 factorial arrangement in a completely randomized design. Dried leaves were milled and assayed for vitamins (pyridoxine, riboflavin, ascorbic acid and tocopherol) and provitamins (total carotene and ergocalciferol). Samples were stored in opaque airtight containers after drying and assayed periodically at weeks 0, 3, 6, 9, 12, 15 and 18 of storage. Air-dried samples had significantly higher (P<0.05) total carotene (1177.49 ?g/100g), pyridoxine (0.59 mg/100g), riboflavin (0.46 mg/100g), ascorbic acid (39.11 mg/100g), ergocalciferol (46.55 ?g/100g) and tocopherol (57.52 ?g/100g) compared with samples dried by other methods. Moringa oleifera leaf type had significantly higher (P<0.05) total carotene (1079.48 ?g/100g), riboflavin (0.41 mg/100g), ergocalciferol (46.40 ?g/100g) and ?-tocopherol (58.45 ?g/100g) while Cucurbita maxima had significantly higher (P<0.05) pyridoxine (0.73 mg/100g). Effects of the interaction of drying methods and leaf type were significant (P<0.05) on the vitamin and provitamin compositions of samples. The effect of the interaction of the oven drying method and leaf type was highly significant (P<0.05) on inherent vitamin and provitamin of samples. Vitamin and provitamin compositions of samples were stable until week six. Air-dried samples contained more vitamins and provitamins which were also more retained in storage.
APA, Harvard, Vancouver, ISO, and other styles
2

Quackenbush, Forrest W., and Robert L. Smallidge. "Nonaqueous Reverse Phase Liquid Chromatographic System for Separation and Quantitation of Provitamins A." Journal of AOAC INTERNATIONAL 69, no. 5 (September 1, 1986): 767–72. http://dx.doi.org/10.1093/jaoac/69.5.767.

Full text
Abstract:
Abstract A reverse phase liquid chromatographic (LC) system has been developed for separating the main naturally occurring carotenoids that have provitamin A activity. The system produces baseline separation of β-carotene, α-carotene, and β-cryptoxanthin (β,β-carotene-3-ol, 472- 70-8) from biologically inactive zeinoxanthin (β, ∊-carotene-3-ol, 24480- 38-4) and from a pigment believed to be α-cryptoxanthin (β,∊-carotene- 3'-ol). Some m-isomers are also separated. These separations are obtained on a C-18 column, isocratically, with methanol-chloroform eluant. For quantitation, peak areas from detection at 475 nm are compared with that of an internal standard, l-(phenylazo)-2-naphthalenol (842-07-9), which elutes prior to the provitamins. Provitamin amounts are calculated from absorbance ratios. Prior to LC, esters are saponified, and interfering pigments are removed from ester-free extracts by adsorption on magnesia.
APA, Harvard, Vancouver, ISO, and other styles
3

Chidiebere-Mark, Nneka M., and Gods’power C. Anyanwu. "Farmers’ preferences and perception influencing decision to grow bio-fortified provitamin A cassava." Journal of Agriculture and Food Sciences 18, no. 1 (August 17, 2020): 130–42. http://dx.doi.org/10.4314/jafs.v18i1.12.

Full text
Abstract:
The study analysed farmers’ preferences and perception influencing decision to grow biofortified provitamin A cassava. Specifically, the study described the socio-economic characteristics of cassava farmers in the study area; identified sources of information on biofortified provitamin A cassava; ascertained farmers’ perception of the key attributes of biofortified provitamin A cassava; ascertained farmers’ preference for biofortified provitamin A cassava; analysed sio-economic determinants of willingness to grow bio-fortified provitamin A cassava, and, constraints that hinder farmers’ decision to grow bio-fortified provitamin A cassava. It was hypothesized that the socio-economic characteristics of farmers significantly influence the decision to grow bio-fortified provitamin A cassava. Structured questionnaire and interview schedule were used to elicit data from 90 cassava farmers in the study area. Data collected were analysed using descriptive and inferential statistics. The result revealed that farmers in the study area were mostly female, married, with a mean age of 50 years, mean years of formal education of 12 years, farming experience of 6 years and a mean household size of 6 persons. The sources of information on bio-fortified provitamin A cassava include agricultural extension agents, farmer groups and radio. The result also showed that farmers perceived bio-fortified provitamin A cassava to be able to make yellow Garri (Cassava granules); have low sugar content. The farmers preferred bio-fortified provitamin A cassava because of its low sugar content, ability to make yellow cassava granules (Garri) which makes it attractive for selling, and contain vitamin A which is necessary to reduce blindness. Poor access to information, poor access to bio-fortified provitamin A cassava stem, and high moisture content were some of the major constraints that affect the decision to grow bio-fortified provitamin A cassava by farmers’ in the study area. The study recommends that farmers should be given easy access to bio-fortified provitamin A cassava stems and extension agents should make more visits to cassava farmers to enlighten them on the benefits of growing biofortified provitamin A cassava. Keywords: Cassava, Biofortified, provitamin A, Farmers, Imo State
APA, Harvard, Vancouver, ISO, and other styles
4

Shrestha, Jiban, and Tika Bahadur Karki. "Provitamin A Maize Development: A Strategy for Fighting against Malnutrition in Nepal." Our Nature 12, no. 1 (March 3, 2015): 44–48. http://dx.doi.org/10.3126/on.v12i1.12256.

Full text
Abstract:
This review paper briefly highlights the importance, challenges and opportunities for adoption of provitamin A rich maize, and potential breeding strategies suitable in the context of Nepal. The biofortified maize with provitamin A could be the convenient, cheaper, and easily accessible source of vitamin A. It can provide a cheap and sustainable form of vitamin A for its deficiency prone communities. Unavailability of suitable maize varieties rich in provitamin A and insufficient nutrition education to the consumers are the major challenges for adoption of provitamin A maize. The introduction, development and commercialization of provitamin A rich maize varieties in collaboration with national and international scientists, CG centers, multinational companies, I/NGOs, government agencies, and private sectors can help to fight against vitamin A induced malnutrition in Nepal. DOI: http://dx.doi.org/10.3126/on.v12i1.12256Our Nature (2014), 12(1): 44-48
APA, Harvard, Vancouver, ISO, and other styles
5

Beswa, Daniso, Muthulisi Siwela, Eric O. Amonsou, and Unathi Kolanisi. "Grain Quality, Provitamin A Carotenoid Profiles, and Sensory Quality of Provitamin A-Biofortified Maize Stiff Porridges." Foods 9, no. 12 (December 21, 2020): 1909. http://dx.doi.org/10.3390/foods9121909.

Full text
Abstract:
Provitamin A-biofortified maize could contribute to the alleviation of vitamin A deficiency (VAD), which is prevalent in sub-Saharan Africa due to a high consumption of starchy, maize-based diets. Four varieties of provitamin A biofortified maize were studied for grain colour, grain texture, thousand kernel weight, and hectolitre mass. Provitamin A biofortified maize stiff porridges were prepared and their retained provitamin A was determined using lutein, zeaxanthin, β-cryptoxanthin, and β-carotene (all-trans and cis isomers) as standards. Provitamin A concentration in the biofortified porridges ranged from 2.24 to 3.18 µg/g and retention from 91–105%. Descriptive sensory analysis and the 5-point facial hedonic test were used to evaluate the sensory quality of the porridges. The biofortified maize porridges were described as sticky, fine, with high intensity residual grain, and having a slightly bitter aftertaste with a cooked maize flavour and aroma, whereas the intensities of these attributes were insignificant in white maize porridge. About 33% of the consumer sample (N = 60) liked the porridges and 28% disliked the porridges, whilst approximately 38% of the consumers were neutral. The findings suggest that biofortified maize stiff porridge can deliver a significant amount of provitamin A to targeted consumers, but the acceptance of biofortified maize still needs to be improved on.
APA, Harvard, Vancouver, ISO, and other styles
6

Strating, J., and H. J. Backer. "Compounds related to provitamin D3 (II). The sulphur analogue of provitamin D3." Recueil des Travaux Chimiques des Pays-Bas 69, no. 7 (September 2, 2010): 909–20. http://dx.doi.org/10.1002/recl.19500690713.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Olawuyi, Odunayo Joseph, Aishat Omotayo Azeez, and Abeeb Abiodun Azeez. "Improvement of Provitamin A in Maize Varieties Using Arbuscular Mycorrhizal Fungus, Glomus clarum." Bio-Research 19, no. 1 (June 30, 2021): 1227–36. http://dx.doi.org/10.4314/br.v19i1.6.

Full text
Abstract:
Arbuscular mycorrhizal fungus (AMF, Glomus clarum) has been used widely as a bio-amendment and bio-control agent in several biotechnological studies. In this study, biofortification of maize with provitamin A using AMF was investigated. Five maize varieties (V1 = white drought-resistant maize, V2= yellow provitamin A maize, V3= white drought-tolerant maize, V4= yellow striga-resistant maize and V5= white striga-resistant maize) were evaluated in a screen house experiment laid out in a completely randomized design with three treatments: T1 = maize + AMF before planting, T2 = maize + AMF, inoculated two weeks after planting and T3 (control) = maize only, and four replications. The result showed that AMF significantly (p<0.05, p = 0.0029) increased the provitamin A level of the maize varieties. White drought-tolerant maize (V3) had the highest provitamin A content (581.57 µg) after harvest, while the least (288.33 µg) was found in white drought-resistant maize (V1). Also, the effect of the treatments on the growth traits (plant height, leaf length, number of leaves per plant) of the maize varieties was highly significant. Therefore, AMF could be considered in breeding maize with high provitamin A content and improved morphological characters.
APA, Harvard, Vancouver, ISO, and other styles
8

Parkes, Elizabeth, Olufemi Aina, Akuwa Kingsley, Peter Iluebbey, Moshood Bakare, Afolabi Agbona, Patrick Akpotuzor, Maryke Labuschagne, and Peter Kulakow. "Combining Ability and Genetic Components of Yield Characteristics, Dry Matter Content, and Total Carotenoids in Provitamin A Cassava F1 Cross-Progeny." Agronomy 10, no. 12 (November 24, 2020): 1850. http://dx.doi.org/10.3390/agronomy10121850.

Full text
Abstract:
Cassava is an important root crop in sub-Saharan Africa, largely cultivated for its starchy edible roots. Biofortified cassava varieties with enhanced provitamin A carotenoid content (PVAC) developed through conventional breeding provide a solution for vitamin A deficiency among vulnerable communities. The aim of this study was to use diallel analysis of six provitamin A cassava genotypes to determine the combining ability, genetic components, heritability, and heterosis of the most important yield characteristics and total carotenoids. Genetic variability for measured characteristics were evident. Fresh root yield was mainly determined by non-additive genetic effects, while dry matter content and total carotenoids were determined by additive effects. Total carotenoids were negatively correlated with fresh root yield, indicating that selection for higher provitamin A content could reduce yield. Mid and higher parent heterosis was seen in some of the crosses for fresh root yield, dry matter content, and total carotenoids. Narrow sense heritability was moderate for fresh root yield and dry matter content, and was high for total carotenoids. This study indicated that yield and dry matter content can be improved in provitamin A cassava but that increased provitamin A content may carry a yield penalty.
APA, Harvard, Vancouver, ISO, and other styles
9

Tang, Guangwen. "Vitamin A Value of Plant Food Provitamin A - Evaluated by the Stable Isotope Technologies." International Journal for Vitamin and Nutrition Research 84, Supplement 1 (December 1, 2014): 25–29. http://dx.doi.org/10.1024/0300-9831/a000183.

Full text
Abstract:
Humans need vitamin A and obtain essential vitamin A by conversion of plant foods rich in provitamin A and/or absorption of preformed vitamin A from foods of animal origin. The determination of the vitamin A value of plant foods rich in provitamin A is important but has challenges. The aim of this paper is to review the progress over last 80 years following the discovery on the conversion of β-carotene to vitamin A and the various techniques including stable isotope technologies that have been developed to determine vitamin A values of plant provitamin A (mainly β-carotene). These include applications from using radioactive β-carotene and vitamin A, depletion-repletion with vitamin A and β-carotene, and measuring postprandial chylomicron fractions after feeding a β-carotene rich diet, to using stable isotopes as tracers to follow the absorption and conversion of plant food provitamin A carotenoids (mainly β-carotene) in humans. These approaches have greatly promoted our understanding of the absorption and conversion of β-carotene to vitamin A. Stable isotope labeled plant foods are useful for determining the overall bioavailability of provitamin A carotenoids from specific foods. Locally obtained plant foods can provide vitamin A and prevent deficiency of vitamin A, a remaining worldwide concern.
APA, Harvard, Vancouver, ISO, and other styles
10

Kockott, D., and B. Herzog. "Photobiologische Wirkungen der Sonnenstrahlung auf die Haut und Schutz durch Sonnenschutzmittel." Aktuelle Dermatologie 44, no. 05 (May 2018): 216–25. http://dx.doi.org/10.1055/s-0043-122327.

Full text
Abstract:
ZusammenfassungDie Wellenlängenabhängigkeit photobiologischer Wirkungen wird durch Wirkungsspektren beschrieben. Die physikalischen Voraussetzungen für die Ermittlung und Anwendung von Wirkungsspektren werden erläutert. Die Bewertung von Strahlungsquellen durch Wirkungsspektren wird am Beispiel der Erythembildung und der Bildung von Provitamin D gezeigt.Die Schutzwirkung von Sonnenschutzmitteln in verschiedenen Spektralbereichen kann durch die Wahl geeigneter UV-Absorber variiert werden. Die Bestimmung von Schutzfaktoren gegenüber erythemwirksamer Strahlung und UVA-Strahlung wird beschrieben. Sonnenschutzmittel reduzieren automatisch auch diejenigen Strahlungsanteile, die für die Produktion von Provitamin D verantwortlich sind. Es wird eine Optimierung von Sonnenschutzmitteln beschrieben, die bei vorgegebenem Erythemschutz ein Optimum an Provitamin D-erzeugender Strahlung auf der Haut zulassen.
APA, Harvard, Vancouver, ISO, and other styles
More sources

Dissertations / Theses on the topic "Provitamin A"

1

Pires, Kelma Maria dos Santos. "AvaliaÃÃo sazonal de carotenÃides provitamina A (αâ e βâ caroteno) e vitamina E (αâtocoferol) em macroalgas marinhas pertencentes a famÃlia Caulerpacea (DivisÃo Chlorophyta)." Universidade Federal do CearÃ, 2007. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=6898.

Full text
Abstract:
FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico
As algas marinhas sÃo fontes de uma grande variedade de compostos benÃficos para o homem, dentre os quais se destacam os minerais, as fibras dietÃrias e as vitaminas (A, B, C e E). O objetivo deste trabalho foi verificar a existÃncia de variaÃÃo sazonal nos teores de α- e β-caroteno (carotenÃides provitamina A) e de α-tocoferol (vitamina E), em cinco espÃcies de macroalgas marinhas pertencentes ao gÃnero Caulerpa (FamÃlia Caulerpaceae, DivisÃo Chlorophyta), âin naturaâ e desidratada. Os conteÃdos desses nutrientes nas algas desidratadas foram comparados com aqueles nas algas âin naturaâ, com o objetivo de verificar se houve alteraÃÃo pelo processo de desidrataÃÃo. As espÃcies de macroalgas marinhas foram coletadas mensalmente, de janeiro a dezembro de 2006, durante as marÃs baixas na Praia do Pacheco, Caucaia- CE. As anÃlises de α- e β-caroteno e α-tocoferol foram realizadas a partir da extraÃÃo da alga em metanol-Ãgua (90:10) nas proporÃÃes 1:10 (p/v), nas amostras âin naturaâ, e 1:20 (p/v), nas desidratadas, saponificaÃÃo com hidrÃxido de potÃssio 5% por 30 min a 70ÂC e partiÃÃo em n-hexano que foi evaporado sob corrente de ar. O resÃduo foi suspenso em 1 mL de metanol no momento da anÃlise cromatogrÃfica e 100 μL foram injetados manualmente. O sistema cromatogrÃfico consistiu em uma coluna Waters Spherisorb-Hichrom S5ODS-2 (4,6 x 250 mm) e uma fase mÃvel constituÃda de metanol:tetrahidrofurano (90:10, v/v), com fluxo de 1,5 mL min-1. O detector foi ajustado em 450 nm e 292 nm e os cromatogramas registrados atravÃs do sistema UnicornTM versÃo 5.0. Todas as espÃcies de Caulerpa âin naturaâ e desidratadas analisadas no presente trabalho apresentaram tanto α-caroteno quanto β-caroteno e as suas distribuiÃÃes mostraram diferenÃas ao longo dos doze meses de coleta. De um modo geral, os teores de α-caroteno foram superiores aos de β-caroteno. As perdas nos conteÃdos de carotenÃides provitamina oscilaram entre 10% e 94%. Para que as algas analisadas neste trabalho fossem consideradas fontes excelentes de vitamina A seria necessÃrio que as porÃÃes consumidas diariamente variassem de 52 g a 689 g, quando consumidas âin naturaâ ou de 42 g a 469 g, quando desidratadas. As cinco espÃcies analisadas neste trabalho apresentaram α-tocoferol, tanto nas amostras âin naturaâ quanto nas desidratadas, com exceÃÃo de C. racemosa coletada em marÃo que apÃs ser submetida a secagem nÃo foi detectado α- tocoferol, e sua distribuiÃÃo foi variÃvel ao longo do ano. Nos teores de α- tocoferol foi observado perdas que variaram de 22 a 91%. As porÃÃes que deveriam ser consumidas diariamente para que as espÃcies de Caulerpa estudadas fossem capazes de fornecer 1/2 da IDR sÃo relativamente pequenas, devendo oscilar entre 11 g e 168 g, quando âin naturaâ, ou entre 13 g e 70 g, quando desidratadas. As quantidades de retinol equivalente e α-tocoferol equivalente nas algas analisadas no presente trabalho nÃo diferiram muito daquelas encontradas nos vegetais normalmente consumidos
Marine macroalgae are sources of a great variety of beneficial compounds such as minerals, dietary fibers and vitamins. The aim of this work was to verify seasonal variation upon both provitamin A carotenoids (α- and β-carotene) and vitamin E (α-tocopherol) contents in five species of the marine green macroalga Caulerpa both fresh and oven-dried at 40ÂC for 15 h. The contents in dried algae were compared to those in fresh algae to evaluate the losses after drying. Algal material was collected monthly from January to December 2006, in Pacheco Beach, Caucaia, CearÃ. Analyses of α- and β-carotene and α-tocopherol were carried out in extracts 1:10 (p/v) for fresh alga and 1:20 (p/v) for dried alga using aqueous methanol (90:10, v/v). They were saponified with 5% KOH and partitioned into n-hexane, which was then evaporated. The residues were suspended in 1 mL methanol prior to HPLC analyses. Aliquots of 100 μL were injected in a HPLC system consisting of a Waters Spherisorb-Hichrom S5 ODS-2 column (4.6 x 250 mm) and a mobile phase of methanol:tetrahydrofurane (90:10, v/v), delivered at 1.5 mL min-1. The detector was set at 450 nm for α- and β-carotene and 290 nm for α-tocopherol. Chromatograms were registered at UnicornTM version 5.0. All samples showed α- and β-carotene and α-tocopherol, but their distribution along the year was variable. In general, the contents of α-carotene were greater than those of β-carotene. The losses of α- and β-carotene varied between 10% and 94%. In order to be considered an excellent source of vitamin A, the daily consumption would be 52 g to 689 g of fresh alga or 42 g to 469 g of dried alga. α-Tocopherol was detected in all samples except in dried C. racemosa collected in March. Similar to the distribution of α- and β-carotene along the year, α-tocopherol contents varied too. Losses varied from 22% to 91%. Daily portions to supply 50% of the Recommended Daily Allowance (RDA) would be 11 g to 168 g of fresh alga or 13 g to 70 g of dried alga. Amounts of vitamin A (retinol equivalents) and vitamin E (tocopherol equivalents) in all algae analyzed were not very different from most vegetables normally consumed
APA, Harvard, Vancouver, ISO, and other styles
2

Siebert, Torsten Uwe. "Four-wave mixing techniques applied to the investigation of non-adiabatic dynamics in polyatomic molecules." Doctoral thesis, [S.l. : s.n.], 2002. http://deposit.ddb.de/cgi-bin/dokserv?idn=966017331.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Pires, Kelma Maria dos Santos. "Avaliação sazonal de carotenóides provitamina A (α– e β– caroteno) e vitamina E (α–tocoferol) em macroalgas marinhas pertencentes a família Caulerpacea (Divisão Chlorophyta)." reponame:Repositório Institucional da UFC, 2007. http://www.repositorio.ufc.br/handle/riufc/18443.

Full text
Abstract:
PIRES, Kelma Maria dos Santos. Avaliação sazonal de carotenóides provitamina A (α– e β– caroteno) e vitamina E (α–tocoferol) em macroalgas marinhas pertencentes a família Caulerpacea (Divisão Chlorophyta). 2007. 94 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Centro de Ciências Agrárias, Departamento de Engenharia de Pesca, Fortalezza-CE, 2007
Submitted by Nádja Goes (nmoraissoares@gmail.com) on 2016-07-18T14:11:47Z No. of bitstreams: 1 2007_dis_kmspires.pdf: 561534 bytes, checksum: 2fbf133b889f47da3a32efc273c3f7ec (MD5)
Approved for entry into archive by Nádja Goes (nmoraissoares@gmail.com) on 2016-07-18T14:12:01Z (GMT) No. of bitstreams: 1 2007_dis_kmspires.pdf: 561534 bytes, checksum: 2fbf133b889f47da3a32efc273c3f7ec (MD5)
Made available in DSpace on 2016-07-18T14:12:01Z (GMT). No. of bitstreams: 1 2007_dis_kmspires.pdf: 561534 bytes, checksum: 2fbf133b889f47da3a32efc273c3f7ec (MD5) Previous issue date: 2007
Marine macroalgae are sources of a great variety of beneficial compounds such as minerals, dietary fibers and vitamins. The aim of this work was to verify seasonal variation upon both provitamin A carotenoids (α- and β-carotene) and vitamin E (α-tocopherol) contents in five species of the marine green macroalga Caulerpa both fresh and oven-dried at 40°C for 15 h. The contents in dried algae were compared to those in fresh algae to evaluate the losses after drying. Algal material was collected monthly from January to December 2006, in Pacheco Beach, Caucaia, Ceará. Analyses of α- and β-carotene and α-tocopherol were carried out in extracts 1:10 (p/v) for fresh alga and 1:20 (p/v) for dried alga using aqueous methanol (90:10, v/v). They were saponified with 5% KOH and partitioned into n-hexane, which was then evaporated. The residues were suspended in 1 mL methanol prior to HPLC analyses. Aliquots of 100 μL were injected in a HPLC system consisting of a Waters Spherisorb-Hichrom S5 ODS-2 column (4.6 x 250 mm) and a mobile phase of methanol:tetrahydrofurane (90:10, v/v), delivered at 1.5 mL min-1. The detector was set at 450 nm for α- and β-carotene and 290 nm for α-tocopherol. Chromatograms were registered at UnicornTM version 5.0. All samples showed α- and β-carotene and α-tocopherol, but their distribution along the year was variable. In general, the contents of α-carotene were greater than those of β-carotene. The losses of α- and β-carotene varied between 10% and 94%. In order to be considered an excellent source of vitamin A, the daily consumption would be 52 g to 689 g of fresh alga or 42 g to 469 g of dried alga. α-Tocopherol was detected in all samples except in dried C. racemosa collected in March. Similar to the distribution of α- and β-carotene along the year, α-tocopherol contents varied too. Losses varied from 22% to 91%. Daily portions to supply 50% of the Recommended Daily Allowance (RDA) would be 11 g to 168 g of fresh alga or 13 g to 70 g of dried alga. Amounts of vitamin A (retinol equivalents) and vitamin E (tocopherol equivalents) in all algae analyzed were not very different from most vegetables normally consumed
As algas marinhas são fontes de uma grande variedade de compostos benéficos para o homem, dentre os quais se destacam os minerais, as fibras dietárias e as vitaminas (A, B, C e E). O objetivo deste trabalho foi verificar a existência de variação sazonal nos teores de α- e β-caroteno (carotenóides provitamina A) e de α-tocoferol (vitamina E), em cinco espécies de macroalgas marinhas pertencentes ao gênero Caulerpa (Família Caulerpaceae, Divisão Chlorophyta), “in natura” e desidratada. Os conteúdos desses nutrientes nas algas desidratadas foram comparados com aqueles nas algas “in natura”, com o objetivo de verificar se houve alteração pelo processo de desidratação. As espécies de macroalgas marinhas foram coletadas mensalmente, de janeiro a dezembro de 2006, durante as marés baixas na Praia do Pacheco, Caucaia- CE. As análises de α- e β-caroteno e α-tocoferol foram realizadas a partir da extração da alga em metanol-água (90:10) nas proporções 1:10 (p/v), nas amostras “in natura”, e 1:20 (p/v), nas desidratadas, saponificação com hidróxido de potássio 5% por 30 min a 70°C e partição em n-hexano que foi evaporado sob corrente de ar. O resíduo foi suspenso em 1 mL de metanol no momento da análise cromatográfica e 100 μL foram injetados manualmente. O sistema cromatográfico consistiu em uma coluna Waters Spherisorb-Hichrom S5ODS-2 (4,6 x 250 mm) e uma fase móvel constituída de metanol:tetrahidrofurano (90:10, v/v), com fluxo de 1,5 mL min-1. O detector foi ajustado em 450 nm e 292 nm e os cromatogramas registrados através do sistema UnicornTM versão 5.0. Todas as espécies de Caulerpa “in natura” e desidratadas analisadas no presente trabalho apresentaram tanto α-caroteno quanto β-caroteno e as suas distribuições mostraram diferenças ao longo dos doze meses de coleta. De um modo geral, os teores de α-caroteno foram superiores aos de β-caroteno. As perdas nos conteúdos de carotenóides provitamina oscilaram entre 10% e 94%. Para que as algas analisadas neste trabalho fossem consideradas fontes excelentes de vitamina A seria necessário que as porções consumidas diariamente variassem de 52 g a 689 g, quando consumidas “in natura” ou de 42 g a 469 g, quando desidratadas. As cinco espécies analisadas neste trabalho apresentaram α-tocoferol, tanto nas amostras “in natura” quanto nas desidratadas, com exceção de C. racemosa coletada em março que após ser submetida a secagem não foi detectado α- tocoferol, e sua distribuição foi variável ao longo do ano. Nos teores de α- tocoferol foi observado perdas que variaram de 22 a 91%. As porções que deveriam ser consumidas diariamente para que as espécies de Caulerpa estudadas fossem capazes de fornecer 1/2 da IDR são relativamente pequenas, devendo oscilar entre 11 g e 168 g, quando “in natura”, ou entre 13 g e 70 g, quando desidratadas. As quantidades de retinol equivalente e α-tocoferol equivalente nas algas analisadas no presente trabalho não diferiram muito daquelas encontradas nos vegetais normalmente consumidos
APA, Harvard, Vancouver, ISO, and other styles
4

Shen, Yanting. "Sorghum pericarp pigments are associated with the contents of carotenoids and provitamin A." Thesis, Kansas State University, 2016. http://hdl.handle.net/2097/34473.

Full text
Abstract:
Master of Science
Food Science Institute - Food, Nutrition, Dietetics and Health
Weiqun Wang
Sorghum is a staple crop consumed in certain regions of Africa and Asia, where vitamin A deficiency is prevalent. However, the correlation of sorghum intake and vitamin A deficiency is inconsistent. The objective of this study was to identify and quantify the carotenoids and pro-vitamin A in the selected sorghum accessions with various pericarp pigments by using LC-MS. Among of total five carotenoids (α-carotene, β-carotene, lutein, zeaxanthin, and β-cryptoxanthin) that were identified and quantitated, three (α-carotene, β-carotene and β-cryptoxanthin) are precursors of vitamin A. The highest content of total carotenoids was detected in the sorghum accessions with yellow pericarp (PI656096, PI585374, PI563448, PI585351), while the highest β-carotene content was found in the accessions with brown or yellow pericarp (PI655996, PI656096, PI585374, PI563448, PI585351). The lowest carotenoids were found in the accessions with white pericarp (PI533943, PI656112, PI565121, PI560493). The pro-vitamin A was 584.9 ± 38.9 ng/g DW in yellow pericarp, 250.6 ± 28.9 ng/g DW in brown pericarp, and 89.0 ± 12.3 ng/g DW in white pericarp, respectively. It appeared the phenotypic diversity of sorghum pericarp colors was strongly associated with the contents of carotenoids and pro-vitamin A, indicating a different impact of various sorghum varieties on vitamin A deficiency and suggesting a possible prevention of vitamin A deficiency by breeding certain sorghum varieties with pericarp pigments.
APA, Harvard, Vancouver, ISO, and other styles
5

Mlalazi, Bulukani. "Defining the role of phytoene synthase in carotenoid accumulation of high provitamin A bananas." Thesis, Queensland University of Technology, 2010. https://eprints.qut.edu.au/48847/1/Bulukani_Mlalazi_Thesis.pdf.

Full text
Abstract:
Vitamin A deficiency (VAD) is a serious problem in developing countries, affecting approximately 127 million children of preschool age and 7.2 million pregnant women each year. However, this deficiency is readily treated and prevented through adequate nutrition. This can potentially be achieved through genetically engineered biofortification of staple food crops to enhance provitamin A (pVA) carotenoid content. Bananas are the fourth most important food crop with an annual production of 100 million tonnes and are widely consumed in areas affected by VAD. However, the fruit pVA content of most widely consumed banana cultivars is low (~ 0.2 to 0.5 ìg/g dry weight). This includes cultivars such as the East African highland banana (EAHB), the staple crop in countries such as Uganda, where annual banana consumption is approximately 250 kg per person. This fact, in addition to the agronomic properties of staple banana cultivars such as vegetative reproduction and continuous cropping, make bananas an ideal target for pVA enhancement through genetic engineering. Interestingly, there are banana varieties known with high fruit pVA content (up to 27.8 ìg/g dry weight), although they are not widely consumed due to factors such as cultural preference and availability. The genes involved in carotenoid accumulation during banana fruit ripening have not been well studied and an understanding of the molecular basis for the differential capacity of bananas to accumulate carotenoids may impact on the effective production of genetically engineered high pVA bananas. The production of phytoene by the enzyme phytoene synthase (PSY) has been shown to be an important rate limiting determinant of pVA accumulation in crop systems such as maize and rice. Manipulation of this gene in rice has been used successfully to produce Golden Rice, which exhibits higher seed endosperm pVA levels than wild type plants. Therefore, it was hypothesised that differences between high and low pVA accumulating bananas could be due either to differences in PSY enzyme activity or factors regulating the expression of the psy gene. Therefore, the aim of this thesis was to investigate the role of PSY in accumulation of pVA in banana fruit of representative high (Asupina) and low (Cavendish) pVA banana cultivars by comparing the nucleic acid and encoded amino acid sequences of the banana psy genes, in vivo enzyme activity of PSY in rice callus and expression of PSY through analysis of promoter activity and mRNA levels. Initially, partial sequences of the psy coding region from five banana cultivars were obtained using reverse transcriptase (RT)-PCR with degenerate primers designed to conserved amino acids in the coding region of available psy sequences from other plants. Based on phylogenetic analysis and comparison to maize psy sequences, it was found that in banana, psy occurs as a gene family of at least three members (psy1, psy2a and psy2b). Subsequent analysis of the complete coding regions of these genes from Asupina and Cavendish suggested that they were all capable of producing functional proteins due to high conservation in the catalytic domain. However, inability to obtain the complete mRNA sequences of Cavendish psy2a, and isolation of two non-functional Cavendish psy2a coding region variants, suggested that psy2a expression may be impaired in Cavendish. Sequence analysis indicated that these Cavendish psy2a coding region variants may have resulted from alternate splicing. Evidence of alternate splicing was also observed in one Asupina psy1 coding region variant, which was predicted to produce a functional PSY1 isoform. The complete mRNA sequence of the psy2b coding regions could not be isolated from either cultivar. Interestingly, psy1 was cloned predominantly from leaf while psy2 was obtained preferentially from fruit, suggesting some level of tissue-specific expression. The Asupina and Cavendish psy1 and psy2a coding regions were subsequently expressed in rice callus and the activity of the enzymes compared in vivo through visual observation and quantitative measurement of carotenoid accumulation. The maize B73 psy1 coding region was included as a positive control. After several weeks on selection, regenerating calli showed a range of colours from white to dark orange representing various levels of carotenoid accumulation. These results confirmed that the banana psy coding regions were all capable of producing functional enzymes. No statistically significant differences in levels of activity were observed between banana PSYs, suggesting that differences in PSY activity were not responsible for differences in the fruit pVA content of Asupina and Cavendish. The psy1 and psy2a promoter sequences were isolated from Asupina and Cavendish gDNA using a PCR-based genome walking strategy. Interestingly, three Cavendish psy2a promoter clones of different sizes, representing possible allelic variants, were identified while only single promoter sequences were obtained for the other Asupina and Cavendish psy genes. Bioinformatic analysis of these sequences identified motifs that were previously characterised in the Arabidopsis psy promoter. Notably, an ATCTA motif associated with basal expression in Arabidopsis was identified in all promoters with the exception of two of the Cavendish psy2a promoter clones (Cpsy2apr2 and Cpsy2apr3). G1 and G2 motifs, linked to light-regulated responses in Arabidopsis, appeared to be differentially distributed between psy1 and psy2a promoters. In the untranscribed regulatory regions, the G1 motifs were found only in psy1 promoters, while the G2 motifs were found only in psy2a. Interestingly, both ATCTA and G2 motifs were identified in the 5’ UTRs of Asupina and Cavendish psy1. Consistent with other monocot promoters, introns were present in the Asupina and Cavendish psy1 5’ UTRs, while none were observed in the psy2a 5’ UTRs. Promoters were cloned into expression constructs, driving the â-glucuronidase (GUS) reporter gene. Transient expression of the Asupina and Cavendish psy1 and psy2a promoters in both Cavendish embryogenic cells and Cavendish fruit demonstrated that all promoters were active, except Cpsy2apr2 and Cpsy2apr3. The functional Cavendish psy2a promoter (Cpsy2apr1) appeared to have activity similar to the Asupina psy2a promoter. The activities of the Asupina and Cavendish psy1 promoters were similar to each other, and comparable to those of the functional psy2a promoters. Semi-quantitative PCR analysis of Asupina and Cavendish psy1 and psy2a transcripts showed that psy2a levels were high in green fruit and decreased during ripening, reinforcing the hypothesis that fruit pVA levels were largely dependent on levels of psy2a expression. Additionally, semi-quantitative PCR using intron-spanning primers indicated that high levels of unprocessed psy2a and psy2b mRNA were present in the ripe fruit of Cavendish but not in Asupina. This raised the possibility that differences in intron processing may influence pVA accumulation in Asupina and Cavendish. In this study the role of PSY in banana pVA accumulation was analysed at a number of different levels. Both mRNA accumulation and promoter activity of psy genes studied were very similar between Asupina and Cavendish. However, in several experiments there was evidence of cryptic or alternate splicing that differed in Cavendish compared to Asupina, although these differences were not conclusively linked to the differences in fruit pVA accumulation between Asupina and Cavendish. Therefore, other carotenoid biosynthetic genes or regulatory mechanisms may be involved in determining pVA levels in these cultivars. This study has contributed to an increased understanding of the role of PSY in the production of pVA carotenoids in banana fruit, corroborating the importance of this enzyme in regulating carotenoid production. Ultimately, this work may serve to inform future research into pVA accumulation in important crop varieties such as the EAHB and the discovery of avenues to improve such crops through genetic modification.
APA, Harvard, Vancouver, ISO, and other styles
6

Ananieva, Valeriya, and Anna Belinska. "Investigation of the influence of sesame antioxidants on the oxidative stability of provitamin A." Thesis, Scientific Route, Estonia, 2019. http://repository.kpi.kharkov.ua/handle/KhPI-Press/48207.

Full text
Abstract:
Microbiological oil solutions of provitamin A (β-carotene) as a dietary supplement are not widely used due to their low oxidation stability. The aim of research is determination of the effect of sesame antioxidants on the oxidative stability of provitamin A in oil solutions. The peroxide number of vegeTable oils is determined by the standard method by the titrimetric method. The value of the period of induction of oil oxidation is determined graphically from the growth curves of peroxide numbers. The content of tocopherols in oils is determined by spectrophotometric method. The content of sesamol and sesamoline in oils is determined by the colorimetric method. The oxidative stability of oils is determined using the accelerated "active oxygen" method. To plan the experiment and process the data, mathematical methods are applied using the software Microsoft Office Excel 2003. The oxidation stability of blended oils (a mixture of sesame, high oleic, sunflower and corn refined oils) and its components is investigated. Blended oil has a lower oxidative stability than sesame oil, but higher than corn and high oleic sunflower. The oxidative stability of the blend is enhanced by the antioxidant content of sesamol and sesamoline. The content of the above antioxidants, as well as the amount of tocopherols, is studied in blended oils. The oxidation stability of the obtained solution of provitamin A in blended oils is investigated. The period of induction of oxidation of blended oils with the addition of 0.2 % β-carotene increases by 1.3 times compared with the period of induction of the original blended oil. Blended long-life oil is recommended to be used to stabilize fat-soluble biologically active compounds.
APA, Harvard, Vancouver, ISO, and other styles
7

Gast, Kai [Verfasser]. "Enrichment of Vitamin E and Provitamin A from Palm Oil Derivates with Supercritical Fluids / Kai Gast." Aachen : Shaker, 2006. http://d-nb.info/1186583010/34.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Kelly, Mary E. Kelly. "Mechanisms Controlling Vitamin A Homeostasis in the Gut and Periphery." Case Western Reserve University School of Graduate Studies / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=case1528476852462429.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Puspitasari-nienaber, Ni Luh. "Stability of carotenoids in Red Palm Oil and its effects on their bioavailability, provitamin a activity and toxicity /." The Ohio State University, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=osu148646270246471.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

Mbabazi, Ruth. "Molecular characterisation and carotenoid quantification of pro-vitamin A biofortified genetically modified bananas in Uganda." Thesis, Queensland University of Technology, 2015. https://eprints.qut.edu.au/84853/1/Ruth_Mbabazi_Thesis.pdf.

Full text
Abstract:
In Uganda, a significant proportion of the population depends on the micronutrient poor East African highland banana as a food staple. Consequently, micronutrient deficiencies such as vitamin A deficiency are an important health concern in the country. To reach most vulnerable rural poor populations, staple crops can be biofortified with essential micronutrients though conventional breeding or genetic engineering. This thesis provided proof of concept that genetically modified East African highland bananas with enhanced provitamin A levels can be generated and fully characterised in Uganda. In addition, provitamin A levels present in popular banana varieties was documented.
APA, Harvard, Vancouver, ISO, and other styles
More sources

Books on the topic "Provitamin A"

1

Miller, Dr Bruce B. Beta-Carotene: The Amazing Provitamin that Promotes & Protects Your Health. Institute for Preventive Health Care, 1985.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
2

Parker, Philip M. The World Market for Provitamin, Vitamin Intermixtures, and Natural Concentrates: A 2007 Global Trade Perspective. ICON Group International, Inc., 2006.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
3

The World Market for Provitamin, Vitamin Intermixtures, and Natural Concentrates: A 2004 Global Trade Perspective. Icon Group International, Inc., 2005.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
4

Parker, Philip M. The 2007 Import and Export Market for Provitamin, Vitamin Intermixtures, and Natural Concentrates in India. ICON Group International, Inc., 2006.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
5

Parker, Philip M. The 2007 Import and Export Market for Provitamin, Vitamin Intermixtures, and Natural Concentrates in China. ICON Group International, Inc., 2006.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
6

Parker, Philip M. The 2007 Import and Export Market for Provitamin, Vitamin Intermixtures, and Natural Concentrates in United States. ICON Group International, Inc., 2006.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
7

Group, Research. The 2000 World Market Forecasts for Imported Provitamins and Vitamins. Icon Group International, 2000.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
8

Parker, Philip M. The World Market for Unmixed Provitamins: A 2007 Global Trade Perspective. ICON Group International, Inc., 2006.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
9

The World Market for Unmixed Provitamins: A 2004 Global Trade Perspective. Icon Group International, Inc., 2005.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
10

The Provitamins and Vitamins Research Gr, The Provitamins, and Vitamins Research Group. The 2000 World Forecasts of Provitamins and Vitamins Export Supplies (World Trade Report). 2nd ed. Icon Group International, 2000.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
More sources

Book chapters on the topic "Provitamin A"

1

Bährle-Rapp, Marina. "Provitamin." In Springer Lexikon Kosmetik und Körperpflege, 457. Berlin, Heidelberg: Springer Berlin Heidelberg, 2007. http://dx.doi.org/10.1007/978-3-540-71095-0_8605.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Bährle-Rapp, Marina. "Provitamin A." In Springer Lexikon Kosmetik und Körperpflege, 457. Berlin, Heidelberg: Springer Berlin Heidelberg, 2007. http://dx.doi.org/10.1007/978-3-540-71095-0_8606.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Perveen, Shagufta, Sara Zafar, Naeem Iqbal, and Muhammad Riaz. "Provitamin A Carotenoids." In Carotenoids: Structure and Function in the Human Body, 775–97. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-46459-2_26.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Bährle-Rapp, Marina. "Provitamin B 5." In Springer Lexikon Kosmetik und Körperpflege, 457. Berlin, Heidelberg: Springer Berlin Heidelberg, 2007. http://dx.doi.org/10.1007/978-3-540-71095-0_8607.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Tang, Guangwen, and Robert M. Russell. "Carotenoids as Provitamin A." In Carotenoids, 149–72. Basel: Birkhäuser Basel, 2009. http://dx.doi.org/10.1007/978-3-7643-7501-0_8.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

Badu-Apraku, Baffour, M. A. B. Fakorede, A. O. Talabi, E. Obeng-Bio, S. G. N. Tchala, and S. A. Oyekale. "Quantitative genetics, molecular techniques and agronomic performance of provitamin a maize in sub-Saharan Africa." In Quantitative genetics, genomics and plant breeding, 276–324. 2nd ed. Wallingford: CABI, 2020. http://dx.doi.org/10.1079/9781789240214.0276.

Full text
Abstract:
Abstract This chapter focuses on quantitative genetics, screening of germplasm collection at the International Institute of Tropical Agriculture, genetic diversity, genetic variation of provitamin A content in maize. Inheritance, heritability, genotype-by-environment for carotenoid content, population improvement, development of open-pollinated varieties were also discussed. Agronomic performance, stress tolerance, combining ability, heterosis were also conducted in sub-Saharan Africa. It may be concluded that maize in sub-Saharan Africa can be effectively subjected to genetic enhancement of provitamin A, along with other mineral components of the kernel and the plant traits for sustainable, high-quality food sufficiency to drastically reduce hunger and malnutrition.
APA, Harvard, Vancouver, ISO, and other styles
7

Kaur, Navneet, Shivani, Ashutosh Pandey, and Siddharth Tiwari. "Provitamin A Enrichment for Tackling Malnutrition." In Banana: Genomics and Transgenic Approaches for Genetic Improvement, 277–99. Singapore: Springer Singapore, 2016. http://dx.doi.org/10.1007/978-981-10-1585-4_19.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Miao, Benchun, and Xiang-Dong Wang. "Provitamin A Carotenoids and Cancer Prevention." In Carotenoids and Human Health, 181–92. Totowa, NJ: Humana Press, 2012. http://dx.doi.org/10.1007/978-1-62703-203-2_11.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Stephensen, Charles B. "Provitamin A Carotenoids and Immune Function." In Carotenoids and Human Health, 261–70. Totowa, NJ: Humana Press, 2012. http://dx.doi.org/10.1007/978-1-62703-203-2_16.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

Hossain, Firoz, Sujay Rakshit, Bhupender Kumar, John J. Amalraj, Vignesh Muthusamy, Bhukya Prakash, Rajkumar U. Zunjare, et al. "Molecular breeding for increasing nutrition quality in maize: recent progress." In Molecular breeding in wheat, maize and sorghum: strategies for improving abiotic stress tolerance and yield, 360–79. Wallingford: CABI, 2021. http://dx.doi.org/10.1079/9781789245431.0021.

Full text
Abstract:
Abstract This chapter presents the status of molecular breeding, especially marker-assisted backcross breeding (MABB), followed in each of the nutritional traits of maize. It focuses on breeding and improvement of protein quality, lysine and tryptophan, provitamin A, vitamin E, phytate, glycaemic index, amylose, and biofortification of maize for human and animal use.
APA, Harvard, Vancouver, ISO, and other styles

Conference papers on the topic "Provitamin A"

1

Terenetskaya, Irina P., and Yury A. Repeyev. "Provitamin D photoisomerization kinetics upon picosecond laser irradiation: role of previtamin conformational nonequilibrium." In Moscow - DL tentative, edited by Sergei A. Akhmanov and Marina Y. Poroshina. SPIE, 1991. http://dx.doi.org/10.1117/12.57382.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Terenetskaya, Irina P. "Provitamin D photoisomerization as possible UV-B monitor: kinetic study using tunable dye-laser." In Ultraviolet Radiation Hazards. SPIE, 1994. http://dx.doi.org/10.1117/12.180825.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Zhu, Kaijie. "Provitamin A biofortification of tomato fruit by overexpressing chromoplast-specific lycopene β-cyclase alleles from citrus." In ASPB PLANT BIOLOGY 2020. USA: ASPB, 2020. http://dx.doi.org/10.46678/pb.20.1374634.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Stojković, Danijela, Verica Jevtić, Maja Đukić, Đorđe Petrović, Sandra Jovičić Milić, and Marijana Kasalović. "SADRŽAJ VITAMINA C U EKSTRAKTIMA ŠIPURKA." In XXVII savetovanje o biotehnologiji. University of Kragujevac, Faculty of Agronomy, 2022. http://dx.doi.org/10.46793/sbt27.541s.

Full text
Abstract:
Rosehip is rich in vitamin C. It also contains provitamin A, B vitamins, vitamin K, as well as many minerals. Rosehip is most often used to produce jams and marmalades. It can also be used to produce drinks because its specific taste and aroma significantly contributes to the appearance and taste of juices. Tea is also the most famous way to use rosehips. Due to the high content of vitamin C and pectin, it can be used for canning food in cooking and for preparing winter food. Medicinal wine can also be made from rose hips. In this paper, extracts of the plant Rosehip obtained by different extraction methods, were examined. The content of extracted substances was determined, as well as the content of vitamin C in order to determine which method will give the best yields of extracts.
APA, Harvard, Vancouver, ISO, and other styles
5

Cola, Florica. "THE INFLUENCE OF SUBCLINICAL MASTITIS ON THE FAT-SOLUBLE VITAMINS AND PROVITAMINS IN COW�S MILK." In 17th International Multidisciplinary Scientific GeoConference SGEM2017. Stef92 Technology, 2017. http://dx.doi.org/10.5593/sgem2017h/63/s30.143.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

Manito, Willy Souza, Brenda Stephany Ferreira Caldas, and Gabriel Carneiro Martins. "COEZIMA COQ10 E SUA IMPORTÂNCIA NA SAÚDE HUMANA: UMA REVISÃO DE LITERATURA." In I Congresso Brasileiro de Saúde Pública On-line: Uma abordagem Multiprofissional. Revista Multidisciplinar em Saúde, 2021. http://dx.doi.org/10.51161/rems/3039.

Full text
Abstract:
Introdução: A Coenzima Q10 (CoQ10), uma provitamina lipossolúvel sintetizada endógenamente, naturalmente encontrada em alimentos ou na forma de suplemento alimentar, também utilizada em formulações cosméticas. Localiza-se na membrana de organelas celulares como o retículo endoplasmático, vesículas e membrana interna da mitocôndria, onde atua como um cofator essencial na cadeia respiratória. Objetivo: O objetivo desta pesquisa, consiste em dispor de informação correspondente, sobre os beneficios da CoQ10 na saúde humana, bem como de apresentar alimentos in natura que apresentam quantidade consideráveis dessa coezima, facilitando assim a disponibilidade de ingestão. A pesquisa consiste em uma revisão da literatura científica, sobre a importância da COQ10 na saúde humana. Material e métodos: A pesquisa foi realizada nas bases de dados eletrônicos, nacionais e internacionais: PubMed, Google Scholar, SciELO, Biblioteca Cochrane, BMC e Scopus. As palavras-chaves utilizadas em combinações para a busca de artigos foram: Efeitos ergogênicos, CoQ10, exercício físico, desportista. Resultados: Na sua forma reduzida, a CoQ10 é um poderoso antioxidante que previne os danos oxidativos causados pelos radicais livres, incluindo a oxidação de lipídios na membrana mitocondrial. A Coenzima Q10 pode ser obtida por duas vias: por via exógena pela ingestão de alimentos e por via endógena, pelo ciclo do mevalonato. Os alimentos que a contêm são rebentos de soja, amêndoas, nozes, vegetais verdes como espinafre , carne, aves domésticas e brócolis. Também pode ser encontrada em peixes gordos, como cavala e sardinha, e em amendoim. Conclusão: A Coenzima Q10 é considerada uma substância ergogênica, atuando no metabolismo celular, com potencial de melhorar o desempenho físico, além disso é um potente antioxidante que atua no combate dos radicais livres, evitando o envelhecimento, fatores que justificam o aumento da procura dessa coenzima nos últimos anos.
APA, Harvard, Vancouver, ISO, and other styles

Reports on the topic "Provitamin A"

1

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

Full text
Abstract:
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.
APA, Harvard, Vancouver, ISO, and other styles
You might also be interested in the extended bibliographies on the topic 'Provitamin A' for particular source types:
Journal articles Dissertations / Theses Books
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!

To the bibliography