scholarly journals Mechanisms involved in the intestinal absorption of dietary vitamin A and provitamin A carotenoids

2012 ◽  
Vol 1821 (1) ◽  
pp. 70-77 ◽  
Author(s):  
Earl H. Harrison
Keyword(s):  
Vitamin A ◽  
Intestinal Absorption ◽  
Provitamin A ◽  
Dietary Vitamin ◽  
Provitamin A Carotenoids

scholarly journals Characterization of cassava ORANGE proteins and their capability to increase provitamin A carotenoids accumulation

PLoS ONE ◽  
2022 ◽  
Vol 17 (1) ◽  
pp. e0262412
Author(s):  
Angélica M. Jaramillo ◽  
Santiago Sierra ◽  
Paul Chavarriaga-Aguirre ◽  
Diana Katherine Castillo ◽  
Anestis Gkanogiannis ◽  
...  
Keyword(s):  
Vitamin A ◽  
Vitamin A Deficiency ◽  
Protein Characterization ◽  
Provitamin A ◽  
Carotenoid Content ◽  
Dietary Vitamin ◽  
Crystal Formation ◽  
Biosynthesis Pathway ◽  
Provitamin A Carotenoids

Cassava (Manihot esculenta Crantz) biofortification with provitamin A carotenoids is an ongoing process that aims to alleviate vitamin A deficiency. The moderate content of provitamin A carotenoids achieved so far limits the contribution to providing adequate dietary vitamin A levels. Strategies to increase carotenoid content focused on genes from the carotenoids biosynthesis pathway. In recent years, special emphasis was given to ORANGE protein (OR), which promotes the accumulation of carotenoids and their stability in several plants. The aim of this work was to identify, characterize and investigate the role of OR in the biosynthesis and stabilization of carotenoids in cassava and its relationship with phytoene synthase (PSY), the rate-limiting enzyme of the carotenoids biosynthesis pathway. Gene and protein characterization of OR, expression levels, protein amounts and carotenoids levels were evaluated in roots of one white (60444) and two yellow cassava cultivars (GM5309-57 and GM3736-37). Four OR variants were found in yellow cassava roots. Although comparable expression was found for three variants, significantly higher OR protein amounts were observed in the yellow varieties. In contrast, cassava PSY1 expression was significantly higher in the yellow cultivars, but PSY protein amount did not vary. Furthermore, we evaluated whether expression of one of the variants, MeOR_X1, affected carotenoid accumulation in cassava Friable Embryogenic Callus (FEC). Overexpression of maize PSY1 alone resulted in carotenoids accumulation and induced crystal formation. Co-expression with MeOR_X1 led to greatly increase of carotenoids although PSY1 expression was high in the co-expressed FEC. Our data suggest that posttranslational mechanisms controlling OR and PSY protein stability contribute to higher carotenoid levels in yellow cassava. Moreover, we showed that cassava FEC can be used to study the efficiency of single and combinatorial gene expression in increasing the carotenoid content prior to its application for the generation of biofortified cassava with enhanced carotenoids levels.

scholarly journals Provitamin A-biofortified maize consumption increases serum xanthophylls and 13C-natural abundance of retinol in Zambian children

2017 ◽  
Vol 242 (15) ◽  
pp. 1508-1514 ◽  
Author(s):  
Jesse Sheftel ◽  
Bryan M Gannon ◽  
Christopher R Davis ◽  
Sherry A Tanumihardjo
Keyword(s):  
Vitamin A ◽  
Natural Abundance ◽  
Provitamin A ◽  
Dietary Vitamin ◽  
Mongolian Gerbils ◽  
Serum Retinol ◽  
Provitamin A Carotenoids ◽  
Effectiveness Studies ◽  
The Impact ◽  
Β Carotene

Plants that undergo C4 photosynthesis, such as maize, are enriched in the stable isotope of carbon (13C) compared with other dietary plants and foods. Consumption of maize that has been biofortified to contain elevated levels of provitamin A carotenoids (orange maize) increased the abundance of 13C in serum retinol of Mongolian gerbils. We evaluated this method in humans to determine if it has potential for further use in intervention effectiveness studies. A random subset of samples from a two-month randomized controlled feeding trial of rural three- to five-year old Zambian children were used to determine the impact of orange maize intake on serum carotenoid concentrations ( n = 88) and 13C-natural abundance in serum retinol ( n = 77). Concentrations of β-cryptoxanthin (a xanthophyll provitamin A carotenoid) and the dihydroxy xanthophylls lutein and zeaxanthin, which do not have vitamin A activity, were elevated in children consuming orange maize compared with those consuming a white maize control ( P < 0.001), while β-carotene was not different ( P > 0.3). Furthermore, 13C natural abundance was higher after two months’ intervention in the orange maize group compared with the white maize group ( P = 0.049). Predictions made from equations developed in the aforementioned gerbil study estimated that maize provided 11% (2–21%, 95% confidence interval) of the recent dietary vitamin A to these children. These results demonstrate that orange maize is efficacious at providing retinol to the vitamin A pool in children through provitamin A carotenoids, as monitored by the change in 13C enrichment, which was not reflected in serum β-carotene concentrations. Further effectiveness studies in countries who have adopted orange maize should consider determining differences in retinol 13C-enrichment among target groups in addition to profiling serum xanthophyll carotenoids with specific emphasis on zeaxanthin. Impact statement Maize biofortified with provitamin A carotenoids (orange) has been released in some African markets. Responsive and sensitive methods to evaluate dissemination effectiveness are needed. This study investigated methods to evaluate effectiveness of orange maize consumption using serum from Zambian children fed orange maize for two months. Many varieties of orange maize contain higher amounts of the xanthophyll carotenoids in addition to β-carotene compared with typical varieties. This study uniquely showed higher concentrations of the maize xanthophylls lutein, zeaxanthin, and β-cryptoxanthin in children who consumed orange maize compared with white. Furthermore, maize is a C4 plant and is therefore naturally enriched with 13C. Higher 13C was detected in the serum retinol of the orange maize consumers with no change in serum β-carotene concentration suggesting preferential bioconversion to retinol. The combined analyses of serum zeaxanthin specifically and 13C-natural abundance of retinol could prove useful in effectiveness studies between orange maize adopters and non-adopters.

scholarly journals Meeting the Vitamin A Requirement: The Efficacy and Importance ofβ-Carotene in Animal Species

2016 ◽  
Vol 2016 ◽  
pp. 1-22 ◽  
Author(s):  
Alice S. Green ◽  
Andrea J. Fascetti
Keyword(s):  
Vitamin A ◽  
Intestinal Absorption ◽  
Animal Species ◽  
Species Differences ◽  
Provitamin A ◽  
Mechanistic Studies ◽  
Provitamin A Carotenoids ◽  
Number Of Factors

Vitamin A is essential for life in all vertebrate animals. Vitamin A requirement can be met from dietary preformed vitamin A or provitamin A carotenoids, the most important of which isβ-carotene. The metabolism ofβ-carotene, including its intestinal absorption, accumulation in tissues, and conversion to vitamin A, varies widely across animal species and determines the role thatβ-carotene plays in meeting vitamin A requirement. This review begins with a brief discussion of vitamin A, with an emphasis on species differences in metabolism. A more detailed discussion ofβ-carotene follows, with a focus on factors impacting bioavailability and its conversion to vitamin A. Finally, the literature on how animals utilizeβ-carotene is reviewed individually for several species and classes of animals. We conclude thatβ-carotene conversion to vitamin A is variable and dependent on a number of factors, which are important to consider in the formulation and assessment of diets. Omnivores and herbivores are more efficient at convertingβ-carotene to vitamin A than carnivores. Absorption and accumulation ofβ-carotene in tissues vary with species and are poorly understood. More comparative and mechanistic studies are required in this area to improve the understanding ofβ-carotene metabolism.

Vitamin A Value of Plant Food Provitamin A - Evaluated by the Stable Isotope Technologies

2014 ◽  
Vol 84 (Supplement 1) ◽  
pp. 25-29 ◽  
Author(s):  
Guangwen Tang
Keyword(s):  
Stable Isotope ◽  
Vitamin A ◽  
Provitamin A ◽  
Animal Origin ◽  
Plant Food ◽  
Plant Foods ◽  
A Value ◽  
Provitamin A Carotenoids ◽  
Β Carotene

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.

scholarly journals Content and Retention of Provitamin A Carotenoids Following Ripening and Local Processing of Four Popular Musa Cultivars from Eastern Democratic Republic of Congo

2012 ◽  
Vol 2 (2) ◽  
pp. 60 ◽  
Author(s):  
Beatrice Nakhauka Ekesa ◽  
Judith Kimiywe ◽  
Inge Van den Bergh ◽  
Guy Blomme ◽  
Claudie Dhuique-Mayer ◽  
...  
Keyword(s):  
Vitamin A ◽  
Palm Oil ◽  
Democratic Republic ◽  
Democratic Republic Of Congo ◽  
Vitamin A Deficiency ◽  
Provitamin A ◽  
Local Processing ◽  
Dietary Intakes ◽  
Republic Of Congo ◽  
Provitamin A Carotenoids

<p>Changes in the concentrations and retention levels of total and individual provitamin A carotenoids (pVACs) during ripening and local processing of the four most popular <em>Musa</em> cultivars of Eastern Democratic Republic of Congo were established through HPLC analysis. The predominant pVACs were all <em>trans</em> ?- and ?-carotene, together constituting about 90% of total pVACs content in raw and processed <em>Musa</em> fruit pulp. The proportion of ?- and ?-carotene was not significantly different in the tested East African Highland Bananas (AAA-EAHB) (‘Nshikazi’ and ‘Vulambya’); in the plantains (‘Musilongo’ and ‘Musheba’), proportion of ?-carotene was almost twice that of ?-carotene. An increase in total pVACs was observed during ripening, with highest levels at ripening stage 3 in all four cultivars. Total pVACs values were as high as 1081µg/100gfw in ‘Vulambya’ and 1819µg/100gfw in ‘Musilongo’. Boiling of the AAA-EAHB and AAB-Plantains resulted to retention of between 40-90% and &gt;95% respectively. Plantains deep-fried in fully-refined palm oil and crude red palm oil for 2 minutes did not seem to lose any pVACs, the levels of total pVACs observed after frying were 100% of what was observed when the fruit was raw. Retinol Activity Equivalents (RAE), in boiled products varied between 22.3 and 173 RAEµg/100gfw, whereas deep fried products had &gt;190 RAEµg/100g edible portion. These results show that the tested AAA-EAHBs and the plantains could meet at least 14% and 30 % of Vitamin A recommended dietary intakes respectively. The findings can therefore guide consumer consumption patterns to maximize vitamin A intake for improved health in these regions and also direct researchers in the selection of <em>Musa</em> cultivars to be incorporated within existing farming systems in the fight against vitamin A deficiency (VAD).</p>

scholarly journals Evaluating Provitamin A Carotenoids and Polar Metabolite Compositions during the Ripening Stages of the Agung Semeru Banana (Musa paradisiaca L. AAB)

2020 ◽  
Vol 2020 ◽  
pp. 1-9
Author(s):  
Rosita D. Chandra ◽  
Chandra A. Siswanti ◽  
Monika N. U. Prihastyanti ◽  
Heriyanto ◽  
Leenawaty Limantara ◽  
...  
Keyword(s):  
Vitamin A ◽  
Organic Acids ◽  
High Performance ◽  
Food Resource ◽  
Dry Weight ◽  
Provitamin A ◽  
Gas Chromatography Mass Spectrometry ◽  
Musa Paradisiaca ◽  
Provitamin A Carotenoids ◽  
Ripening Stages

Banana cultivars that are rich in provitamin A carotenoids and other nutrients may offer a potential food source to help alleviate vitamin A deficiencies, particularly in developing countries. The local plantain type banana, Agung Semeru (Musa paradisiaca L.), was investigated, in order to analyse the changes in the compositions of the provitamin A carotenoids and metabolite compounds, including the amino acids, organic acids, and sugars, during the ripening stage as this banana is widely processed for food products in either the unripe, ripe, or overripe stages. The bananas that had reached the desired ripening stages were subjected to high-performance liquid chromatography (HPLC) analysis, and the results indicated that the total provitamin A carotenoid concentrations ranged between 4748.83 μg/100 g dry weight (dw) and 7330.40 μg/100 g dw, with the highest level of vitamin A activity at 457.33±5.18 μg retinol activity equivalents (RAE)/100 g dw. Compared to the Cavendish variety, which is consumed worldwide, the Agung Semeru banana had vitamin A activity that was 40 to 90 times higher, dependent on the stage of ripening. The breakdown of the starch during the ripening stages resulted in an increase of its sugar compounds, such as sucrose, fructose, and glucose, as well as its dominant organic acids, such as malic acid, oxalic acid, and citric acid, which were observed using gas chromatography-mass spectrometry (GC-MS) during the ripening stages. The findings of this study show that the Agung Semeru banana is a promising fruit that could be widely produced as a nutritional and energy food resource, due to its high levels of vitamin A activity and sugars.

scholarly journals The Human Enzyme That Converts Dietary Provitamin A Carotenoids to Vitamin A Is a Dioxygenase

2014 ◽  
Vol 289 (19) ◽  
pp. 13661-13666 ◽  
Author(s):  
Carlo dela Seña ◽  
Kenneth M. Riedl ◽  
Sureshbabu Narayanasamy ◽  
Robert W. Curley ◽  
Steven J. Schwartz ◽  
...  
Keyword(s):  
Vitamin A ◽  
Provitamin A ◽  
Provitamin A Carotenoids ◽  
Human Enzyme

scholarly journals Can Increased Vegetable Consumption Improve Iron Status?

1996 ◽  
Vol 17 (1) ◽  
pp. 1-3 ◽  
Author(s):  
Saskia de Pee ◽  
Clive E. West ◽  
Muhilal ◽  
Darwin Karyadi ◽  
Joseph G. A. J. Hautvast
Keyword(s):  
Vitamin A ◽  
Intervention Studies ◽  
Vegetable Consumption ◽  
Iron Status ◽  
Provitamin A ◽  
Review Of The Literature ◽  
Fortified Foods ◽  
Plant Foods ◽  
Provitamin A Carotenoids ◽  
Vitamin A Status

Theoretically, vegetable consumption could improve iron status. First, vegetables contain iron. Second, when the provitamin A carotenoids in vegetables improve vitamin A status, the result could be increased iron levels. Most studies on vegetable consumption have focused on improvements in vitamin A status, and only very few have addressed iron status. From a review of the literature and a recent study in Indonesia, we conclude that the data on the effectiveness of vegetables to improve the levels of both nutrients are inconclusive. The bioavailability of both iron and provitamin A carotenoids might be lower than expected. It is necessary to conduct other intervention studies using plant foods, animal foods, and fortified foods. In the meantime, other strategies that have been proved to reduce iron and vitamin A deficiencies should continue.

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