Carotenoid Absorption Research Articles

Chlorophyll and carotenoid quantifications in white grape ( Vitis vinifera L.) skins by reflectance spectroscopy

In white grapes, chlorophylls and carotenoids play important roles in berry color and environmental interactions (e.g. radiative stresses). In this paper, easy, fast and low cost non-invasive reflectance methods have been tested and developed. Previously published indexes showed good performances for chlorophyll quantifications. However, in this work, new formulas able to discriminate chlorophylls a and b were also proposed. The wavelengths of major interest for the absorption detection were identified. Formulas based on the Gaussians half heights were proposed. In general, chlorophyll quantifications were obtained directly from reflectance spectra, while carotenoid absorption bands did not allow good reflectance correlations. However, the chlorophyll/carotenoid ratio (due to the pigments physiological linked roles) could be used to estimate carotenoid concentration. Their proportion changes during berry development, thus the index coefficients should be adapted in relation to the BBCH phenological phase. The obtained indexes demonstrated good correlations with the destructive quantifications. These methods could support further researches concerning cultivar classification and physiological studies

Absorption of Carotenoids and Mechanisms Involved in Their Health-Related Properties.

Carotenoids participate in the normal metabolism and function of the human body. They are involved in the prevention of several diseases, especially those related to the inflammation syndrome. Their main mechanisms of action are associated to their potent antioxidant activity and capacity to regulate the expression of specific genes and proteins. Recent findings suggest that carotenoid metabolites may explain several processes where the participation of their parent carotenoids was unclear. The health benefits of carotenoids strongly depend on their absorption and transformation during gastrointestinal digestion. The estimation of the 'bioaccessibility' of carotenoids through in vitro models have made possible the evaluation of the effect of a large number of factors on key stages of carotenoid digestion and intestinal absorption. The bioaccessibility of these compounds allows us to have a clear idea of their potential bioavailability, a term that implicitly involves the biological activity of these compounds.

Carotenoids as a Source of Antioxidants in the Diet.

Carotenoids, widely distributed fat-soluble pigments, are responsible for the attractive colorations of several fruits and vegetables commonly present in our daily diet. They are particularly abundant in yellow-orange fruits (carrots, tomatoes, pumpkins, peppers, among others) and, although masked by chlorophylls, in dark green leafy vegetables. Several health benefits have been attributed to carotenoids or to foods rich in these pigments, by means of different mechanisms-of-action, including the role as provitamin A of almost 50 different carotenoids and the antioxidant activity that protects cells and tissues from damage of free radicals and singlet oxygen, providing enhancement of the immune function, protection from sunburn reactions and delaying the onset of certain types of cancer. Common food sources and the efficiency of the absorption of carotenoids, analytical approaches used for measurement of their antioxidant effect and an overview of some epidemiological studies that have been performed to assess the beneficial impact of carotenoids in human health are outlined in this chapter.

ROLE OF DIETARY SUPPLEMENTATION IN PREVENTING PROGRESSION OF AGE-RELATED MACULAR DEGENERATION

Age-related macular degeneration (AMD) is a chronic, progressive, degenerative eye disease affecting the central retina. It is the leading cause of blindness among individuals of 65 years and older. In the early stage patients have drusen and/or alterations of pigmentation in the macular region. This disease can progress to geographic atrophy and/or choroidal neovascularization. It has been shown that oxidative stress and hypoxia are important in the pathogenesis of AMD. Patients may gain some visual improvement with inhibitors of vascular endothelial growth factor, but complete restoration of visual function is achieved only in small cases. No effective therapies are known for atrophic AMD. Many large observational studies have shown that dietary antioxidant supplementation is beneficial in preventing the progression of AMD from early to late stages. The Age-Related Eye Disease Study (AREDS) demonstrated that daily oral supplementation with vitamins C (500 mg) and E (400 IU), beta carotene (15 mg), zinc (80 mg) and copper (2 mg) reduced the risk of progression to advanced AMD by 25% at 5 years. In primary analyses AREDS II failed to show further reduce of this risk by addition of lutein (10 mg) and zeaxanthin (2mg), or/and omega-3 long-chain polyunsaturated fatty acids [docosahexaenoic acid (350 mg DHA) and eicosapentaenoic acid 650 mg (EPA)] to the AREDS formulation. But there was no true placebo group. The simultaneous administration of beta carotene, lutein and zeaxanthin may suppress tissue level of the both laters because of competitive absorption of carotenoids. Subgroup analyses revealed that dietary supplementation with lutein, zeaxanthin and AREDS formulation without beta carotene may reduce the risk of progression to advanced AMD.The LUNA (Lutein nutrition effects measured by autofluorescence) study demonstrated that supplementation with lutein (12 mg), zeaxanthin (1 mg), vitamin C (120 mg), vitamin E (17,6 mg), zinc (10 mg), selenium (40 mg) resulted in a significant augmentation of macular pigment optical density (MPOD). This effect was more prominent in cases with initial low level of MPOD. The CARMA (Carotenoids in Age-Related Maculopathy) Study has shown that lutein (6 mg), zeaxanthin (0,3 mg), vitamin C (75 mg), vitamin E (7,5 mg), zinc (10 mg) and copper (0,2 mg) prevented progression from early to late stages of AMD. Early intervention is more effective in maintaining visual function.

Eicosapentaenoic acid inhibits intestinal β-carotene absorption by downregulation of lipid transporter expression via PPAR-α dependent mechanism

The involvement of lipid transporters, the scavenger receptor class B, type I (SR-BI) and Niemann–Pick type C1 Like 1 protein (NPC1L1) in carotenoid absorption is demonstrated in intestinal cells and animal models. Dietary ω-3 fatty acids are known to possess antilipidemic properties, which could be mediated by activation of PPAR family transcription factors. The present study was conducted to determine the effect of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), on intestinal β-carotene absorption. β-carotene uptake in Caco-2/TC7 cells was inhibited by EPA (p < 0.01) and PPARα agonist (P < 0.01), but not by DHA, PPARγ or PPARδ agonists. Despite unaltered β-carotene uptake, both DHA and PPARδ agonists inhibited the NPC1L1 expression. Further, EPA also induced the expression of carnitine palmitoyl transferase 1A (CPT1A) expression, a PPARα target gene. Interestingly, EPA induced inhibition of β-carotene uptake and SR B1 expression were abrogated by specific PPARα antagonist, but not by PPARδ antagonist. EPA and PPARα agonist also inhibited the basolateral secretion of β-carotene from Caco-2 cells grown on permeable supports. These results suggest that EPA inhibits intestinal β-carotene absorption by down regulation of SR B1 expression via PPARα dependent mechanism and provide an evidence for dietary modulation of intestinal β-carotene absorption.

Bioavailability of β-cryptoxanthin is greater from pasteurized orange juice than from fresh oranges - a randomized cross-over study.

Orange fruits and products thereof represent important dietary sources of carotenoids, particularly β-cryptoxanthin. Since previous studies reported a positive effect of vegetable processing on carotenoid absorption, our objective was to compare the bioavailability of β-cryptoxanthin from either fresh navel oranges (Citrus sinensis L. Osbeck) or pasteurized orange juice. The study was designed as a randomized 2-way cross-over study. Twelve volunteers consumed two meals delivering 744 μg of β-cryptoxanthin from either fresh navel oranges or pasteurized orange juice. Eight blood samples were collected over 9.5 h after test meal consumption and analyzed using HPLC-DAD. Additionally, carotenoid bioaccessibility was assessed after in vitro digestion of the same test foods. β-cryptoxanthin bioavailability from pasteurized orange juice was 1.8-fold higher than from fresh oranges (P = 0.011). Similarly, mean absorption of the non-dose adjusted carotenoids lutein (P = 0.301), zeaxanthin (P = 0.216), and zeinoxanthin (P = 0.090) were slightly higher from orange juice, although not reaching statistical significance. The in vitro digestion revealed a 5.3-fold higher bioaccessibility of β-cryptoxanthin from orange juice. Dietary fiber contents in the test foods were inversely associated with carotenoid bioavailability. Orange juice represents a more bioavailable source of β-cryptoxanthin than fresh oranges.

Effects of egg consumption on carotenoid absorption from co-consumed, raw vegetables

Dietary lipids are one of the most effective stimulators of carotenoid absorption, but very limited data exist on the impact of endogenous food sources of lipids to enhance carotenoid absorption. The co-consumption of whole egg with carotenoid-rich foods may increase overall carotenoid absorption via lipid-rich egg yolk. We designed this study to assess the effects of egg consumption on carotenoid absorption from a carotenoid-rich, raw mixed-vegetable salad. Healthy young men (n = 16) consumed the same salad (all served with 3 g canola oil) with no egg (control), 75 g scrambled whole eggs (1.5 eggs) [low egg (LE)], and 150 g scrambled whole eggs (3 eggs) [high egg (HE)] (a randomized crossover design). Control, LE, and HE meals contained 23 mg, 23.4 mg (0.4 mg from eggs), and 23.8 mg (0.8 mg from eggs) total carotenoids and 3 g, 10.5 g (7.5 g from eggs), and 18 g (15 g from eggs) total lipids, respectively. Blood was collected hourly for 10 h, and the triacylglycerol-rich lipoprotein (TRL) fraction was isolated. Total and individual carotenoid contents, including lutein, zeaxanthin , α-carotene, β-carotene, and lycopene in TRL were analyzed, and composite areas under the curve (AUCs) were calculated. The total mean (±SE) carotenoid AUC0-10h in TRL was higher for the HE meal than for LE and control meals [125.7 ± 19.4(a) compared with 44.8 ± 9.2(b) compared with 14.9 ± 5.2(b) nmol/L · 10 h, respectively (values without a common superscript letter differ); P < 0.0001]. The TRL AUC(0-10h) of lutein and zeaxanthin increased 4-5-fold (P < 0.001), and the TRL AUC(0-10h) of carotenoid not present in eggs, including α-carotene, β-carotene, and lycopene, increased 3-8-fold (P < 0.01) for the HE meal compared with the control meal. These findings support the claim that co-consuming cooked whole eggs is an effective way to enhance carotenoid absorption from other carotenoid-rich foods such as a raw mixed-vegetable salad. This trial was registered at clinicaltrials.gov as NCT01951313.

Effects of Whole Egg Consumption on Carotenoids Absorption from Co‐Consumed, Carotenoids‐Rich Mixed‐Vegetable Salad

Dietary lipid is one of the most effective stimulators of carotenoids (CAT) absorption, but very limited data exist on the impact of endogenous food sources of lipid to enhance CAT absorption. Co‐consuming whole egg which contains lutein (LUT) and zeaxanthin (ZEA), with CAT‐rich foods may increase overall CAT absorption via lipid rich egg yolk. The objective of this study was to assess the effects of egg consumption on CAT absorption from a CAT‐rich, raw mixed‐vegetable salad. Healthy young males (n=16) consumed the same salad (all served with 3g canola oil) with no egg (control, C); with 75g (1½ eggs) of scrambled whole egg (low egg, LE); and with 150g (3 eggs) of scrambled whole egg (high egg, HE) (randomized, crossover design). C, LE, and HE trials included 3g, 10.5g (7.5g from eggs), and 18g (15g from eggs) of total lipid, respectively. Blood was collected hourly for 10h and triacylglycerol rich lipoprotein fractions (TRL) were isolated. Total and individual CAT contents, including LUT, ZEA, α‐carotene (α‐C), β‐carotene (β‐C), and lycopene (LYC) in TRL were analyzed and composite areas under the curve (AUC) were calculated. Total CAT AUC0‐10h in TRL was higher for HE vs. LE and C (125.9±14.1a vs. 46.0±14.1b vs. 15.6±13.6b nmol•L−1•h, p&lt;0.0001). 2 and 5‐fold increases (p&lt;0.001) in TRL AUC0‐10h of LUT and ZEA and 2 to 4 and 4 to 9‐fold increases (p&lt;0.01) in TRL AUC0‐10h of CAT beyond those found in egg such as α‐C, β‐C, and LYC were observed for HE compared to LE and C. These findings support that co‐consuming whole eggs is an effective way to increase both CAT content and absorption of CAT from raw vegetables.Support: American Egg Board; NIH UL1TR001108; Purdue Ingest Behav Res Ctr

An SCD gene from the Mollusca and its upregulation in carotenoid-enriched scallops

Carotenoids are a diverse group of red, orange, and yellow pigments that act as vitamin A precursors and antioxidants. Animals can only obtain carotenoids through their diets. Amongst the carotenoids identified in nature, over one third are of marine origin, but current research on carotenoid absorption in marine species is limited. Bivalves possess an adductor muscle, which is normally white in scallops. However, a new variety of Yesso scallop (Patinopecten yessoensis), the ‘Haida golden scallop’, can be distinguished by its adductor muscle's orange colour, which is caused by carotenoid accumulation. Studying the genes related to carotenoid accumulation in this scallop could benefit our understanding of the mechanisms underlying carotenoid absorption in marine organisms, and it could further improve scallop breeding for carotenoid content. Stearoyl-CoA desaturase (SCD) is the rate-limiting enzyme in the production of monounsaturated fatty acids, which enhance carotenoid absorption. Here, the full-length cDNA and genomic DNA sequences of the SCD gene from the Yesso scallop (PySCD) were obtained. The PySCD gene consisted of four exons and three introns, and it contained a 990-bp open reading frame encoding 329 amino acids. It was ubiquitously expressed in adult tissues, embryos and larvae of both white Yesso scallops and ‘Haida golden’ scallops. Although the expression pattern of PySCD in both types of scallops was similar, significantly more PySCD transcripts were detected in the ‘Haida golden’ scallops than in the white scallops. Elevated PySCD expression was found in tissues including the adductor muscle, digestive gland, and gonad, as well as in veliger larvae. This study represents the first characterisation of an SCD gene from the Mollusca. Our data imply that PySCD functions in multiple biological processes, and it might be involved in carotenoid accumulation.

A Review of the Structure, Biosynthesis, Absorption of Carotenoids-Analysis and Properties of their Common Natural Extracts

Carotenoids are a class of natural pigments familiar to all through the orange-red colours of popular foods like oranges, tomatoes and carrots and the yellow colour of many flowers. They have been studied for a number of years because of their diverse roles in photobiology, photochemistry and photo medicine. Carotenoids are also added as colorants to many manufactured foods, drinks, and animal feeds, either in the forms of natural extracts (e.g annatto, paprika or marigold extracts) or as pure compounds manufactured by chemical synthesis. Carotenoids are often described as provitamins A, as this particular vitamin is a product of carotenoid metabolism. The distribution of carotenoids among the different plant groups shows no obvious pattern. b-Carotene is the most abundant in leafy vegetables, though the colour is masked by its co-existence with chlorophyll, and this carotenoid has the highest vitamin A activity. Zeaxanthin, a-carotene and antheraxanthin are also present in small amounts. In the tomato, lycopene is the major carotenoid, while fruits contain varying proportions of cryptoxanthin, lutein and antheraxanthin. In this review paper the natural occurrence of carotenoids (with focus on certain natural extracts) is described along with its structure and physicochemical properties. The biosynthesis - industrial synthesis and absorption of carotenoids is also discussed. Finally, a brief overview of analysis and properties of commonly available natural carotenoid extracts (annato, paprika, xanthophylls, lycopene) are also reported.

A genetic dissection of intestinal fat-soluble vitamin and carotenoid absorption.

Carotenoids are currently investigated regarding their potential to lower the risk of chronic disease and to combat vitamin A deficiency. Surprisingly, responses to dietary supplementation with these compounds are quite variable between individuals. Genome-wide studies have associated common genetic polymorphisms in the BCO1 gene with this variability. The BCO1 gene encodes an enzyme that is expressed in the intestine and converts provitamin A carotenoids to vitamin A-aldehyde. However, it is not clear how this enzyme can impact the bioavailability and metabolism of other carotenoids such as xanthophyll. We here provide evidence that BCO1 is a key component of a regulatory network that controls the absorption of carotenoids and fat-soluble vitamins. In this process, conversion of β-carotene to vitamin A by BCO1 induces via retinoid signaling the expression of the intestinal homeobox transcription factor ISX. Subsequently, ISX binds to conserved DNA-binding motifs upstream of the BCO1 and SCARB1 genes. SCARB1 encodes a membrane protein that facilitates absorption of fat-soluble vitamins and carotenoids. In keeping with its role as a transcriptional repressor, SCARB1 protein levels are significantly increased in the intestine of ISX-deficient mice. This increase results in augmented absorption and tissue accumulation of xanthophyll carotenoids and tocopherols. Our study shows that fat-soluble vitamin and carotenoid absorption is controlled by a BCO1-dependent negative feedback regulation. Thus, our findings provide a molecular framework for the controversial relationship between genetics and fat-soluble vitamin status in the human population.

Tomato (Solanum lycopersicum) Carotenoids and Lycopenes Chemistry; Metabolism, Absorption, Nutrition, and Allied Health Claims—A Comprehensive Review

Tomato (Solanum lycopersicum) is one of the most essential herbaceous plants that have been probed against various life sight related disorders owing to array of phytochemicals. It is important source of vitamin C, potassium, folic acid, and carotenoids, such as lycopene. Carotenoids are the pigments synthesized during fruit ripening and responsible for the final red color of the tomato. Consumption of tomato and tomato-based products contribute to the absorption of carotenoids and lycopenes in human serum. Lycopene is chemically acyclic carotene with 11 conjugated double bonds, normally in transconfiguration while isomerization occur in blood plasma for its better absorption. It has ability for adenosine deaminase inhibition that plays important role in the regression of tumor. Tomato also contain other active compounds, namely, neoxanthin, lutein, α-cryptoxanthin, α-carotene, β-carotene, cyclolycopene, and β-carotene 5, 6-epoxide. These components provide synergistic effect against various threats but still need further attention of the researchers. Both in vitro and in vivo studies have elucidated the potential of tomato against variety of metabolic syndromes. Latest research highlights the relationship between consuming tomato and its products with reduced risk of various maladies like obesity, hyperglycemic and hypercholesterolemic attributes, cardiovascular disorders, and cancer insurgences. Moreover, tomato and its bioactive components hold potential to become effective modules in diet-based regimens; however, integrated research and meta-analysis are still required to enhance meticulousness.

Stark absorption spectroscopy on the carotenoids bound to B800–820 and B800–850 type LH2 complexes from a purple photosynthetic bacterium, Phaeospirillum molischianum strain DSM120

Stark absorption spectroscopy was applied to clarify the structural differences between carotenoids bound to the B800–820 and B800–850 LH2 complexes from a purple photosynthetic bacterium Phaeospirillum (Phs.) molischianum DSM120. The former complex is produced when the bacteria are grown under stressed conditions of low temperature and dim light. These two LH2 complexes bind carotenoids with similar composition, 10% lycopene and 80% rhodopin, each with the same number of conjugated CC double bonds (n=11). Quantitative classical and semi-quantum chemical analyses of Stark absorption spectra recorded in the carotenoid absorption region reveal that the absolute values of the difference dipole moments |Δμ| have substantial differences (2 [D/f]) for carotenoids bound to either B800–820 or B800–850 complexes. The origin of this striking difference in the |Δμ| values was analyzed using the X-ray crystal structure of the B800–850 LH2 complex from Phs. molischianum DSM119. Semi-empirical molecular orbital calculations predict structural deformations of the major carotenoid, rhodopin, bound within the B800–820 complex. We propose that simultaneous rotations around neighboring CC and CC bonds account for the differences in the 2 [D/f] of the |Δμ| value. The plausible position of the rotation is postulated to be located around C21–C24 bonds of rhodopin.

Optical properties, ethylene production and softening in mango fruit

Firmness decay, chlorophyll breakdown and carotenoid accumulation, controlled by ethylene, are major ripening events in mango fruit. Pigment content and tissue structure affect the optical properties of the mesocarp, which can be measured nondestructively in the intact fruit by time-resolved reflectance spectroscopy (TRS). This work is aimed at improving the maturity assessment in mango (Mangifera indica L. cv Haden) from Brazil, using TRS absorption in both the carotenoid and chlorophyll regions in order to develop a model for fruit ripening. Scattering and absorption in the 540–900nm spectral range by TRS, ethylene production and respiration rate, and firmness, were measured in one day on each individual fruit of a sample covering the range of maturity. The fruit displayed a variability which was attributed to the different biological age. Absorption spectra showed two peaks at 540 and 670nm, corresponding respectively to the tail of carotenoid absorption and to chlorophyll-a absorption. Carotenoids increased substantially only in fruit where chlorophyll had almost disappeared. The absorptions at 540 and 670nm, which described the maturity state of each fruit relative to the range of each wavelength, were combined in one index of biological age (biological shift factor) for each fruit and used in logistic models of ethylene increase and firmness decay respectively. The model explained about 80% of the variability in ethylene production rate. A similar result was obtained for firmness when scattering was added in the model. The combination of absorption at 540 and 670nm measured by TRS in the intact fruit can be used to classify mango fruit according to maturity and to predict the ripening of individual fruit.

Plasma carotenoid levels in passerines are related to infection by (some) parasites

Plumage coloration plays an important role in intra and inter-sexual competition in birds. Many of the yellow, orange or red colours present in birds are carotenoid dependent. Carotenoids can not be synthetized de novo by birds and consequently should be obtained through their diet, and access to carotenoids may differ between individuals and species. In addition to ornamentation, carotenoids are important for bird physiology and it has been proposed that a trade-off in their allocation to these two functions occurs. Under this scenario parasites may play a central role in maintaining the honesty of plumage as a signaling system by increasing the demands for carotenoids for infection or damage control and/or by reducing carotenoid absorption in the intestines. We analyzed the relationship between (1) carotenoid concentrations in plasma and (2) blood and intestinal parasite richness and abundance in 22 species of passerines sampled in spring. Loads of different groups of parasites were unrelated so conclusions drawn from examining a particular group of parasites cannot be extrapolated to the whole community of pathogens and parasites inhabiting a host. At intraspecific level plasma carotenoid concentration was negatively related to the richness of intestinal parasites and the abundance of some groups of intestinal parasites, at interspecific level plasma carotenoid concentration was negatively related with the abundance of intestinal parasites. No relationship at intra- nor interpecific level was found between carotenoids and blood parasites. The results suggest that intestinal parasites play an important role in the evolution and maintenance of carotenoid-derived sexually selected ornamentations probably through a negative impact on the uptake of carotenoids at the gut.

Large plasmonic fluorescence enhancement of cyanobacterial photosystem I coupled to silver island films

A large, two-orders-of-magnitude enhancement of fluorescence emission from cyanobacterial Photosystem I (PSI) coupled to plasmonic excitations in silver island films was observed. Such a high value has not been reported for metal-enhanced fluorescence of photosynthetic pigment-protein complexes before. The dramatic enhancement of the PSI emission occurs when PSI is excited resonantly into the Qx and Qy bands of chlorophyll a. In contrast, excitation in the carotenoid absorption band yields ten times lower enhancement factors. We attribute these large values of enhancement factor to plasmon-induced activation of excitation and emission channels absent for isolated PSI complexes.

Influence of olive oil on carotenoid absorption from tomato juice and effects on postprandial lipemia

The potential benefits of tomato-rich diets for the cardiovascular system have been related to plasma concentrations of carotenoids. In addition, the bioavailability of carotenoids from foods depends on their chemical structure, processing and the food matrix. Our aim was to evaluate the effect of adding oil to tomato juice (not treated with heat) on the bioavailability of plasma carotenoids and postprandial lipid response. In a randomized, controlled, crossover feeding trial, eleven healthy volunteers were assigned to receive a single ingestion of 750g of tomato juice (TJ) containing 10% of refined olive oil/70kg body weight (BW) and 750g of TJ without oil/70kg BW on two different days. All lycopene isomers increased significantly in subjects consuming TJ with oil, reaching the maximum concentration at 24h. LDL cholesterol and total cholesterol decreased significantly 6h after the consumption of TJ with oil, which significantly correlated with an increase of trans-lycopene and 5-cis-lycopene, respectively.

Relationship between tissue firmness and optical properties of ‘Royal Gala’ apples from 400 to 1050 nm

Absorption and reduced scattering coefficients were measured between 400 and 1050nm for ‘Royal Gala’ apples using the inverse adding-doubling technique. Relationships between penetrometer, acoustic firmness and the optical properties are identified. Carotenoid (400–500nm), and to a lesser extent chlorophyll-a (680nm), absorptions were found to correlate with penetrometer firmness, with correlation coefficients equal to −0.69 and 0.52 respectively. The reduced scattering coefficient across all wavelengths increased as fruit softened. An average correlation coefficient of −0.68 was found between the reduced scattering coefficient (550–900nm) and penetrometer firmness. No correlation was found between the AWETA acoustic firmness and either of the optical properties. A correction was developed to improve the correlation between penetrometer firmness and carotenoid absorption. This compensated for errors introduced by light loss in the inverse adding-doubling system and improved the correlation from −0.68 to −0.78.

Effects of lecithin in salad dressing on the plasma appearance of fat‐soluble micronutrients consumed in salads: contributions of chylomicrons and large VLDL (645.16)

The objectives were to investigate the effects of the lecithin/oil ratio in salad dressing on the absorption of: 1) carotenoids, phylloquinone, and tocopherols from salad vegetables; 2) retinyl palmitate formed in the intestine from the provitamin A carotenoids. An additional objective was to investigate the roles of plasma chylomicrons and large very‐low‐density lipoproteins (VLDLA) in the transport of the newly‐absorbed fat‐soluble micronutrients. Healthy women (n = 12) each consumed 3 identical salads with 3 different salad dressings, which each contained 4 g of phylloquinone‐ and tocopherol‐stripped soybean oil. The soybean oil contained (by wt) 0%, 1% or 4% added hydroxylated soy lecithin. The order in which the salads were consumed was randomly assigned; salads were separated by 蠅 2 weeks. Blood was collected at baseline and 2, 3.5, 5, 7, and 9.5 h postprandially. Chylomicrons and VLDLA were analyzed by HPLC with coulometric array electrochemical detection. The hydroxylated soy lecithin in the amounts added to the oil in the salad dressing did not enhance the absorption of carotenoids, retinyl palmitate, phylloquinone, or tocopherols. The majority of the absorbed carotenoids, retinyl palmitate, and phylloquinone were contained within large VLDL (P &lt; 0.01). Thus lipoproteins and/or their remnants in this subfraction have a major role in the transport of newly‐absorbed carotenoids and fat‐soluble vitamins.

Dietary Intake of Vitamin A and Macronutrients among Pregnant Women in Ngaoundere Town, Adamawa Region, Cameroon

This paper examines the risk of Vitamin A deficiency among selected pregnant women in Ngaoundere, Adamawa Region, Cameroon. A total of one hundred (100) pregnant women attending ante natal visits at the Regional Hospital in Ngaoundere were involved in a survey conducted in 2012 which used a 24-hour dietary recall to assess their dietary intake. Food models were used to assist memory and portion sizes of food taken. Carotenoids were quantified in the meals commonly consumed, as well as proteins, sugar, fibers and oil, nutrients intervening in carotenoids absorption and vitamin A metabolism. The results indicated that the dietary intake of vitamin A was inadequate with 37.5% of the selected pregnant women exposed to acute vitamin A deficiency, while 20% of them were exposed to the severe form. The daily consumption of vitamin A was about 539.09 ± 43.09 μg, corresponding to a contribution of 67.39% to the vitamin A requirement of the pregnant women. The dietary intake of macronutrients was also inadequate with a daily consumption of 57.28 ± 12 g for oils, 177.88 ± 29 g for sugars, 47.34 ± 11 g for proteins and 11.28 ± 3 g for fibers corresponding respectively to a contribution of 63.6%, 70.8%, 78.90% and 45.1% of these nutrients requirement in these women. Given that over 50% of the women surveyed were exposed to vitamin A deficiency, there is a need for urgent intervention programs in the area to alleviate this situation.