Β-carotene Content Research Articles

Effects of dietary fat type and emulsification on carotenoid absorption: a randomized crossover trial

BackgroundAlthough emerging evidence has suggested that the type and emulsification of dietary fat may be important to carotenoid absorption, these effects have not yet been validated in a human trial. ObjectivesThis study aimed to examine the effects of dietary fat type and emulsification on the bioaccessibility and bioavailability of carotenoids from a carotenoid-rich salad. MethodsAn identical salad was used for the in vitro and the human trial. This was paired with 28 g of one of the following 4 different fats: 1) nonemulsified olive oil, 2) emulsified olive oil, 3) nonemulsified coconut oil, and 4) emulsified coconut oil. The bioaccessibility of total carotenoids (TCs) was assessed by a simulated in vitro digestion model. Sixteen subjects consumed salad with 4 test fats in random order, and plasma triglyceride and carotenoid (lutein, zeaxanthin, α-carotene, β-carotene, and lycopene) concentrations were determined hourly for 10 h following the consumption. The absorption of TC and individual carotenoids was evaluated by the positive incremental AUC (iAUC) of plasma carotenoid concentrations. ResultsThe bioaccessibility of TC was greater with olive oil (24.0%) than with coconut oil (14.9%), and with the oil being emulsified (23.5%) rather than that being nonemulsified (15.4%). Similarly, the positive iAUC1–10h of TC, α-carotene, and lycopene were 55.2%, 110.8%, and 45.8%, respectively, higher with olive oil than with coconut oil. Emulsified fat induced 40.0% greater positive iAUC1–10h of TC than nonemulsified fat. ConclusionsThe type and emulsification of dietary fat are both essential to carotenoid absorption. Findings from this study may provide scientific support for designing excipient emulsions as potential dietary strategies to optimize the absorption of fat-soluble compounds.This study was registered at clinicaltrials.gov as NCT04323826.

Evaluation and quantification of associations between commonly suggested milk biomarkers and the proportion of grassland-based feeds in the diets of dairy cows.

This study is a first step approach towards the prediction of the proportion of grassland-based feeds (%GB) in dairy cow diets with the aid of three different groups of milk biomarkers. We aimed to evaluate and quantify the associations between biomarkers commonly suggested in the literature and %GB in individual cows as a hypothesis-generating stage for the prospective establishment of accurate %GB prediction models. Consumers and governments financially encourage sustainable, local milk production making grass-based feeding, in grassland-dominated regions, of major interest. Milk from grassland-fed cows differs from that of other feeding systems by inferential fatty acids (FA), β-carotene content and yellow color; however, these biomarkers have not been evaluated together for their association with %GB. Using approved methods of parametric regression analysis, gas chromatography (GC), mid-infrared spectra (MIR) and color spectroscopy, we aimed to develop a first step towards an easy-to-implement, cost-effective milk-based control to estimate %GB in dairy cow diets. The underlying database was generated with 24 cows each fed one of 24 different diets gradually increasing in grass silage and decreasing in corn silage. Our results indicate that GC-measured α-linolenic acid, total n-3 FA and the n-6:n-3 ratio, MIR-estimated PUFA and milk red-green color index a* are robust milk biomarkers for constructing accurate prediction models to determine %GB. Based on simplified regression analysis, diets containing 75% GB should contain ≥ 0.669 and 0.852 g α-linolenic acid and total n-3 FA per 100 g total FA, respectively, and an n-6:n-3 FA ratio of < 2.02 measured with GC; estimated with MIR, polyunsaturated FA should be ≥ 3.13 g/100 g total FA. β-carotene was not a good predictor for estimating %GB. Unexpectedly, the milk became greener with increasing %GB (negative a* values, ‒6.416 for 75% GB), suggesting the red-green color index, not yellow-blue, as a suitable biomarker.

Short-Term Moderate Energy Restriction Does Not Affect Indicators of Oxidative Stress and Genotoxicity in Humans

Restriction of energy intake (ER), without malnutrition of essential nutrients, has repeatedly been demonstrated to increase longevity in rodents. In the antioxidant theory of aging the lack of balance between the generation of free radicals and free radical scavenging was thought to be a main causal agent in the aging process. From this point of view the antiaging effect induced by ER might be due to the lower rate of free-radical production and related damage induced by a lower metabolic rate. The antiaging effects of ER might also occur in humans. This study explored the effects of a 10-week moderately energy-restricted diet (80% of habitual) in 24 non-obese middle-aged men (16 ER subjects, 8 controls) on resting metabolic rate (RMR) and indicators of the primary antioxidant defense system, oxidative stress and genotoxicity. RMR decreased significantly in both groups, even when adjustments were made for the change in body composition. The increase in blood vitamin C concentrations correlated with the increase in urinary 8-hydroxy-deoxyguanosine (80HdG) excretion. The change in urinary 80HdG excretion also correlated with the change in RMR per kg fat-free mass. No differences between groups were found for changes in indicators of genotoxicity, erythrocyte catalase, glutathione peroxidase and superoxide dismutase activity and in plasma vitamin E, A or β-carotene concentrations. We conclude that 10 weeks of moderate ER did not affect indicators of antioxidative capacity, oxidative stress and genotoxicity of humans. Since subjects were not in energy balance at the end of the study, no conclusions can be made with respect to long-term effects.

High-quality genome assembly and genetic mapping reveal a gene regulating flesh color in watermelon (Citrullus lanatus).

The unique color and type characteristics of watermelon fruits are regulated by many molecular mechanisms. However, it still needs to be combined with more abundant genetic data to fine-tune the positioning. We assembled genomes of two Korean inbred watermelon lines (cv. 242-1 and 159-1) with unique color and fruit-type characteristics and identified 23,921 and 24,451 protein-coding genes in the two genomes, respectively. To obtain more precise results for further study, we resequenced one individual of each parental line and an F2 population composed of 87 individuals. This identified 1,539 single-nucleotide polymorphisms (SNPs) and 80 InDel markers that provided a high-density genetic linkage map with a total length of 3,036.9 cM. Quantitative trait locus mapping identified 15 QTLs for watermelon fruit quality-related traits, including β-carotene and lycopene content in fruit flesh, fruit shape index, skin thickness, flesh color, and rind color. By investigating the mapping intervals, we identified 33 candidate genes containing variants in the coding sequence. Among them, Cla97C01G008760 was annotated as a phytoene synthase with a single-nucleotide variant (A → G) in the first exon at 9,539,129 bp of chromosome 1 that resulted in the conversion of a lysine to glutamic acid, indicating that this gene might regulate flesh color changes at the protein level. These findings not only prove the importance of a phytoene synthase gene in pigmentation but also explain an important reason for the color change of watermelon flesh.

Egg yolk plasma enriched with β-carotene through the diet of laying hens and adding it to the extender improves the quality of frozen semen in Arabic stallions.

Equine semen cryopreservation is one of the major procedures for the genetic conservation of rare and endangered genotypes. The current study was conducted to evaluate the effect of egg yolk plasma (EYP) enriched with β-carotene as an antioxidant supplement on INRA-96 extender regarding freezing Arabic stallion sperm. For this purpose, β-carotene various concentrations were utilized as a supplementary ingredient in formulating the diets of laying hens. Birds were randomly divided into four groups, fed with 0 (control), 500, 1000 and 2000 mg/kg in a supplemented diet with β-carotene. Subsequently, various variants of enriched extender (INRA-96 + 2.5% glycerol [G]) were gained by adding 2% EYP from four treatment groups. The sperm characteristics, including motility, viability, morphology, plasma membrane integrity (HOS test), lipid peroxidation (MDA) and DNA fragmentation, were evaluated after thawing. According to the results obtained in this study, the addition of EYP from T2 and T4 (500 and 2000 mg/kg of β-carotene in hens' diet) to the extender (INRA-96 + 2.5% G) leads to an increase in total motility (50.50% and 49.49%, respectively), progressive motility (32.6% and 31.8%, respectively), viability (68.7% and 66.1%, respectively) and plasma membrane integrity (57.7% and 50.6%, respectively). Moreover, lipid peroxidation (1.3 and 1.4nmol/mL, respectively) and DNA fragmentation (8.6% and 9.9%, respectively) were diminished using the mentioned treatments. However, sperm morphology was not affected by the treatments. In the current study, we concluded that the optimal concentration of β-carotene in the laying hen's diet (500 mg/kg) could reveal the best results about sperm quality. So, EYP enriched with β-carotene acts as a valuable natural and safe supplementary material that could be exploited for enhancing stallion sperm quality in cryopreservation conditions.

Patterns of Dietary Blood Markers Are Related to Frailty Status in the FRAILOMIC Validation Phase.

The influence of nutritional factors on frailty syndrome is still poorly understood. Thus, we aimed to confirm cross-sectional associations of diet-related blood biomarker patterns with frailty and pre-frailty statuses in 1271 older adults from four European cohorts. Principal component analysis (PCA) was performed based on plasma levels of α-carotene, β-carotene, lycopene, lutein + zeaxanthin, β-cryptoxanthin, α-tocopherol, γ-tocopherol and retinol. Cross-sectional associations between biomarker patterns and frailty status, according to Fried's frailty criteria, were assessed by using general linear models and multinomial logistic regression models as appropriate with adjustments for the main potential confounders. Robust subjects had higher concentrations of total carotenoids, β-carotene and β-cryptoxanthin than frail and pre-frail subjects and had higher lutein + zeaxanthin concentrations than frail subjects. No associations between 25-Hydroxyvitamin D3 and frailty status were observed. Two distinct biomarker patterns were identified in the PCA results. The principal component 1 (PC1) pattern was characterized by overall higher plasma levels of carotenoids, tocopherols and retinol, and the PC2 pattern was characterized by higher loadings for tocopherols, retinol and lycopene together and lower loadings for other carotenoids. Analyses revealed inverse associations between PC1 and prevalent frailty. Compared to participants in the lowest quartile of PC1, those in the highest quartile were less likely to be frail (odds ratio: 0.45, 95% CI: 0.25-0.80, p = 0.006). In addition, those in the highest quartile of PC2 showed higher odds for prevalent frailty (2.48, 1.28-4.80, p = 0.007) than those in the lowest quartile. Our findings strengthen the results from the first phase of the FRAILOMIC project, indicating carotenoids are suitable components for future biomarker-based frailty indices.

Nutritional, sensory, and antioxidant characteristics of composite multigrain flour biscuits blended with sweet potato flour

Biscuits prepared using composite flour (CF) blends made from multigrain flour (MGF) and sweet potato flour (SPF) were compared with biscuits prepared using wheat flour (WF; control). Three proportions of MGF:SPF were used to prepare CF biscuits: T1 (80:10), T2 (75:15), and T3 (70:20), while 100% WF biscuits served as control. MGF enriched the biscuits with antioxidants, dietary fibre, and protein. The addition of SPF produced softer biscuits. When 5% each of pumpkin flour (PF) and extruded soy chunk flour (ESF) were added to CF biscuits, it helped in improving their colour, texture, and taste scores. The physicochemical, antioxidant, textural, and sensory analyses were performed on both CF and control biscuits, and results showed a significant difference in nutritional contents between them. Substitution of wheat flour with MGF in experimental biscuits led to a significant increase in protein contents of T1 and T2 samples. Fibre and ash contents were the highest for T3 sample at 1.52 and 1.71%, respectively. T3 sample was also found to have higher levels of antioxidant activity (22%) and total phenolic content (234 mg GAE/100 g). The CF biscuits had a higher β-carotene content (390 to 823 µg/100 g). CF biscuits were darker in colour and less hard. T3 sample gave a sensory performance comparable to that of the control. Therefore, the present work suggested that composite multigrain flour with sweet potato flour can be used to produce biscuits with superior nutritional, antioxidant, and sensory qualities as compared to ordinary wheat biscuits.

Functional characterization of transcriptional activator gene SIARRI in tomato reveals its role in fruit growth and ripening.

Auxins regulate several characteristics of plant development and growth. Here, we characterized a new transcriptional activator SIARRI which binds specific DNA sequences and was revealed in Arabidopsis (ARR1). SIARRI acts as a two-component response regulator and its Arabidopsis homologous gene is AT3G16857. It belongs to the subfamily of type-B response regulators in the cytokinin signaling pathway. The study aimed to characterize the transgenic Micro-Tom plants by the overexpression of Solanum lycopersicum two-component response regulator ARR1. Overexpression of SIARRI results in a pleiotropic phenotype during fruit development and ripening. This study indicates that SIARRI is a primary regulator of leaf morphology and fruit development. Moreover, overexpressed plants showed variations in growth related to auxin as well as shorter hypocotyl elongation, enlarged leaf vascularization, and decreased apical dominance. The qRT-PCR investigation revealed that expression was downregulated at the breaker stage and high at Br+6 at various stages of fruit growth and ripening. In contrast to the fruit color, lycopene and β-carotene concentrations in red-yellow overexpression line fruits were reduced significantly, and also slightly reduced in some red fruits. The quantity of β-carotene in the transgenic fruits was lower than that of lycopene. This study showed that this gene might be a new transcriptional activator in fruit development and ripening. Furthermore, this study will provide new insights into tomato fruit ripening.

Can consumption of local micronutrient- and absorption enhancer-rich plant foods together with starchy staples improve bioavailable iron and zinc in diets of at-risk African populations?

Iron and zinc deficiencies remain prevalent in developing countries, often due to monotonous starchy diets that are low in bioavailable minerals. This review addresses the question as to whether consumption of starchy staple foods in Africa together with micronutrient-dense and absorption enhancer-rich plant foods can enhance iron and zinc bioavailability in the diets of at-risk populations. While green leafy vegetables (GLVs) fortification of starchy staples can improve mineral contents, especially iron, it may not improve bioavailable iron and zinc, due to GLVs’ high contents of mineral absorption inhibitors, notably polyphenols, phytate and calcium. Fruits, although low in minerals, could improve bioavailable iron and zinc in the staples because of their high ascorbic and citric acid and/or β-carotene contents, which can form soluble chelates with the minerals. More human studies are needed to establish whether such a technology or fortification strategy can improve bioavailable iron and zinc in African-type plant-based diets.

Unravelling effects of red/far-red light on nutritional quality and the role and mechanism in regulating lycopene synthesis in postharvest cherry tomatoes

The main goal of this study was to explore the role of red/far-red light in the preservation of postharvest quality in cherry tomato fruits and the mechanism of red/far-red light in regulation of lycopene synthesis. Results showed that red/far-red light irradiation inhibited weight loss and promoted colour change during storage, and it also increased the content of lycopene and β-carotene compared to control. Gene PSY, ZDS and LCY-b were overexpressed in fruits treated with red/far-red light during 33 days’ storage compared to control. The analysis of genes involved in red/far-red light absorbance (PHYA and PHYB) and mediation (HY5 and PIF3), and fruit ripening (ACS2 and RIN) suggests that red/far-red light promote lycopene accumulation through phytochrome-mediated signalling pathway to induce HY5. Elevated HY5 could either directly bind to PSY or promote the expression of ACS2 to induce RIN through MADS-loop to enhanced lycopene content.

Regulation of carotenoid and flavonoid biosynthetic pathways in Lactuca sativa var capitate L. in protected cultivation.

In the face of a growing world population and limited land, there is an urgent demand for higher productivity of food crops, and cultivation systems must be adapted to future needs. Sustainable crop production should aim for not only high yields, but also high nutritional values. In particular, the consumption of bioactive compounds such as carotenoids and flavonoids is associated with a reduced incidence of non-transmissible diseases. Modulating environmental conditions by improving cultivation systems can lead to the adaption of plant metabolisms and the accumulation of bioactive compounds. The present study investigates the regulation of carotenoid and flavonoid metabolisms in lettuce (Lactuca sativa var capitate L.) grown in a protected environment (polytunnels) compared to plants grown without polytunnels. Carotenoid, flavonoid and phytohormone (ABA) contents were determined using HPLC-MS and transcript levels of key metabolic genes were analyzed by RT-qPCR. In this study, we observed inverse contents of flavonoids and carotenoids in lettuce grown without or under polytunnels. Flavonoid contents on a total and individual level were significantly lower, while total carotenoid content was higher in lettuce plants grown under polytunnels compared to without. However, the adaptation was specific to the level of individual carotenoids. For instance, the accumulation of the main carotenoids lutein and neoxanthin was induced while the β-carotene content remained unchanged. In addition, our findings suggest that the flavonoid content of lettuce depends on transcript levels of the key biosynthetic enzyme, which is modulated by UV light. A regulatory influence can be assumed based on the relation between the concentration of the phytohormone ABA and the flavonoid content in lettuce. In contrast, the carotenoid content is not reflected in transcript levels of the key enzyme of either the biosynthetic or the degradation pathway. Nevertheless, the carotenoid metabolic flux determined using norflurazon was higher in lettuce grown under polytunnels, suggesting posttranscriptional regulation of carotenoid accumulation, which should be an integral part of future studies. Therefore, a balance needs to be found between the individual environmental factors, including light and temperature, in order to optimize the carotenoid or flavonoid contents and to obtain nutritionally highly valuable crops in protected cultivation.

Nutritional evaluation, oxidative indexes, and functional properties of Irish potatoes, eggs, and red kidney beans based complementary food

Background: Protein-energy malnutrition (PEM) remains a serious public health concern in Cameroon. This disorder is frequent in childhood and is primarily caused by a deficiency in energy, protein, and micronutrients. Aims: This study aimed to develop novel complementary foods from suitable sources of proteins and minerals such as Irish potatoes (Solanum tuberosum L.), red kidney beans (Phaseolus vulgaris L.), and egg flours. Material and Methods: Different flours were prepared from local raw materials. Four blends (1 to 4) were formulated at different proportions and the nutritional composition, oxidative indexes, urease activity, and techno-functional properties of blends were assessed and compared to the Irish potato flour (control). Results: The protein (16.1 to 24.23 %) content was significantly (p &lt; 0.05) higher in blends than in the control (10.88 %). Blend 3 (60 % Irish potato, 25% Egg yolk, 15 % Egg white) showed the highest total calorie value (396.69 Kcal/100 g). Magnesium (2084 to 2470 mg/100 g), and iron (10.9 to 14.7 mg/100 g) contents were higher in blends than in the control (2053 and 9.9 mg/100 g respectively). Vitamins C and β-carotene contents in blends were 9.99 – 13.03 and 0.94 – 2.34 mg/ 100 g respectively. The peroxide value ranged from 5.3 to 8.98 meq O2 /Kg oil. Blend 3 showed the lowest urease activity (0.73 expressed as ΔpH). Concerning the techno-functional properties, the lowest bulk density (0.79 g/cm3) was obtained in blend 3. Blends 3 and 4 showed the lowest water absorption capacity (2.35 and 2.25 mL/g) and swelling capacity with 5.86 and 5.16 mg/g respectively. Conclusions: From our investigation, blend 3 could be used as a base for complementary foods as this blend presents the most nutritive and present the best techno-functional characteristics. Keywords: Blends, nutritional composition, peroxide value, urease activity, techno-functional properties.

Averrhoa carambola L., Cyphomandra betacea, Myrciaria dubia as a Source of Bioactive Compounds of Antioxidant Properties.

Natural bioactive compounds play an important role in the prevention of various diseases. The exotic fruits Averrhoa carambola L. (star fruit), Cyphomandra betacea (tamarillo) and Myrciaria dubia (camu-camu) can be valuable sources of phytochemicals with antioxidant properties. The aim of this study has been to compare the antioxidant properties of these exotic fruits, the structure of polyphenolic compounds and the content of vitamin C and β-carotene. All the juices were analyzed for their antioxidant capacity (DPPH and ABTS assays) and the composition of phenolic compounds (TP and FBBB assays, total flavonoid content, total anthocyanins). In addition, HPLC assays were performed to analyse the content of phenolic acids, flavonoids, vitamin C and β-carotene. The results demonstrated that juice from the Myrciaria dubia fruit had the highest antioxidant capacity, which was 4.5-fold higher than that of juice from Averrhola carambola L., and nearly 7-fold higher than the antioxidant capacity of Cyphomandra betacea fruit juice. Additionally, juice from the camu-camu fruit had a 3- to 4-fold higher total polyphenol content (8290 ± 254 mg GAE L-1) and a high level of vitamin C (8410.8 ± 16.9 mg AA kg-1). In turn, tamarillo juice had a high content of total anthocyanins (5796 mg CGE L-1) and phenolic acids (mostly chlorogenic acid and caffeic acid). Juice produced from carambola had a high content of total flavonoids (1345 mg CAE L-1), and the composition of these compounds was dominated by flavanols (epicatechin). The research results justify the conclusion that fruits of Myrciaria dubia, Averrhoa carambola L., Cyphomandra betacea are rich sources of bioactive compounds with antioxidant properties, and in the near future may serve as healthful food ingredients.

Bioactive Compounds of Shrimp Shell Waste from Palaemon serratus and Palaemon varians from Portuguese Coast

The production and consumption of shrimp species create massive amounts of shrimp bio-waste. In this study, shrimp shell waste from Palaemon serratus and Palaemon varians from the Portuguese coast was characterized. Regarding the antioxidant capacity, the obtained values were between 4.7 and 10.4 mg gallic acid equivalents (GAE)/g dry weight (dw) for Total phenolic content (TPC); 3 and 7 mg ascorbic acid equivalents (AAE)/g dw for Ferric reducing antioxidant power assay (FRAP); 0.4 and 1.2 mg Trolox equivalent (TE)/g dw for 2,2-diphenyl-1-picryl-hydrazyl-hydrate free radical scavenging (DPPH•); 4 and 11 mg TE/g dw for 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging activity (ABTS•+); and 72 and 130 mg TE/g dw for Oxygen radical absorbance capacity (ORAC). For the antimicrobial activity, shrimp shell waste from P. varians formed inhibition zones between 14 and 23 mm. Total carotenoid content values were in the range of 28 and 134 μg/g dw, and according to their HPLC-PAD profile, β-carotene and astaxanthin contents were between 0.3 and 7.6 μg/g dw and 1.1 and 26.1 μg/g dw, respectively. These studies are critical to recognizing the potential added value of shrimp shell waste as possible colorants and preservatives with antioxidant protection capacity to be used in the food industry.

Hydrogen-assisted facile synthesis of N,N,N-trimethyl chitosan stabilized zinc oxide nanoparticles and its influence on the quality of Solanum lycopersicum L

The climacteric nature of tomatoes results in the rapid deterioration of the fruit which in turn reduces the shelf-life. Herein, the role of N,N,N-trimethyl chitosan zinc oxide nanoparticles (NTMC-ZnONPs) and the additive advantage in the quality and/or shelf-life extension of post-harvested tomato fruits was investigated. NTMC-ZnONPs was synthesized through green reduction of zinc salt in the presence of clean hydrogen gas and water-soluble N,N,N-Trimethyl chitosan as a stabilizing agent. The UV–Vis spectroscopic measurement shows that NTMC-ZnONPs exhibit a strong surface plasmon resonance at 360 nm which is true for ZnONPs. The detailed characterization of NTMC-ZnONPs confirmed the formation of ZnONPs with an average particle size of 37.6 nm. Furthermore, varied concentrations of NTMC-ZnONPs were applied by dipping unblemished tomato fruit in the solution of NTMC-ZnONPs for 60 s and thereafter stored in a plastic container. Physicochemical quality parameter data of the NTMC-ZnONPs-treated tomato fruit were collected, namely: color, total suspended solids (TSS), vitamin C, lycopene, pH, β-carotene, shelf life, and firmness. NTMC-ZnONPs were found to significantly improve the fruit firmness, color, β-carotene content, shelf-life, and taste of tomato fruit while the TSS was found to increase as ripening progresses. Therefore, this study ascertains the applicability and/or suitability of green NTMC-ZnONPs in the enhancement of fruit quality when coated with NTMC-ZnONPs during storage.

Retinol and Pro-Vitamin A Carotenoid Nutritional Status during Pregnancy Is Associated with Newborn Hearing Screen Results

The prenatal period is critical for auditory development; thus, prenatal influences on auditory development may significantly impact long-term hearing ability. While previous studies identified a protective effect of carotenoids on adult hearing, the impact of these nutrients on hearing outcomes in neonates is not well understood. The purpose of this study is to investigate the relationship between maternal and umbilical cord plasma retinol and carotenoid concentrations and abnormal newborn hearing screen (NHS) results. Mother-infant dyads (n = 546) were enrolled at delivery. Plasma samples were analyzed using HPLC and LC-MS/MS. NHS results were obtained from medical records. Statistical analysis utilized Mann-Whitney U tests and logistic regression models, with p ≤ 0.05 considered statistically significant. Abnormal NHS results were observed in 8.5% of infants. Higher median cord retinol (187.4 vs. 162.2 μg/L, p = 0.01), maternal trans-β-carotene (206.1 vs. 149.4 μg/L, p = 0.02), maternal cis-β-carotene (15.9 vs. 11.2 μg/L, p = 0.02), and cord trans-β-carotene (15.5 vs. 8.0 μg/L, p = 0.04) were associated with abnormal NHS. Significant associations between natural log-transformed retinol and β-carotene concentrations and abnormal NHS results remained after adjustment for smoking status, maternal age, and corrected gestational age. Further studies should investigate if congenital metabolic deficiencies, pesticide contamination of carotenoid-rich foods, maternal hypothyroidism, or other variables mediate this relationship.

The transcription factor IbNAC29 positively regulates the carotenoid accumulation in sweet potato.

Carotenoid is a tetraterpene pigment beneficial for human health. Although the carotenoid biosynthesis pathway has been extensively studied in plants, relatively little is known about their regulation in sweet potato. Previously, we conducted the transcriptome database of differentially expressed genes between the sweet potato (Ipomoea batatas) cultivar 'Weiduoli' and its high-carotenoid mutant 'HVB-3'. In this study, we selected one of these candidate genes, IbNAC29, for subsequent analyses. IbNAC29 belongs to the plant-specific NAC (NAM, ATAF1/2, and CUC2) transcription factor family. Relative IbNAC29 mRNA level in the HVB-3 storage roots was ~1.71-fold higher than Weiduoli. Additional experiments showed that the contents of α-carotene, lutein, β-carotene, zeaxanthin, and capsanthin are obviously increased in the storage roots of transgenic sweet potato plants overexpressing IbNAC29. Moreover, the levels of carotenoid biosynthesis genes in transgenic plants were also up-regulated. Nevertheless, yeast one-hybrid assays indicated that IbNAC29 could not directly bind to the promoters of these carotenoid biosynthesis genes. Furthermore, the level of IbSGR1 was down-regulated, whose homologous genes in tomato can negatively regulate carotene accumulation. Yeast three-hybrid analysis revealed that the IbNAC29-IbMYB1R1-IbAITR5 could form a regulatory module. Yeast one-hybrid, electrophoretic mobility shift assay, quantitative PCR analysis of chromatin immunoprecipitation and dual-luciferase reporter assay showed that IbAITR5 directly binds to and inhibits the promoter activity of IbSGR1, up-regulating carotenoid biosynthesis gene IbPSY. Taken together, IbNAC29 is a potential candidate gene for the genetic improvement of nutritive value in sweet potato.

Engineering the β-Carotene Metabolic Pathway of Microalgae Dunaliella To Confirm Its Carotenoid Synthesis Pattern in Comparison To Bacteria and Plants.

Dunaliella salina is the most salt-tolerant eukaryote and has the highest β-carotene content, but its carotenoid synthesis pathway is still unclear, especially the synthesis of lycopene, the upstream product of β-carotene. In this study, DsGGPS, DsPSY, DsPDS, DsZISO, DsZDS, DsCRTISO, and DsLYCB genes were cloned from D. salina and expressed in Escherichia coli. A series of carotenoid engineering E. coli strains from phytoene to β-carotene were obtained. ZISO was first identified from Chlorophyta, while CRTISO was first isolated from algae. It was found that DsZISO and DsCRTISO were essential for isomerization of carotenoids in photosynthetic organisms and could not be replaced by photoisomerization, unlike some plants. DsZDS was found to have weak beta cyclization abilities, and DsLYCB was able to catalyze 7,7',9,9'-tetra-cis-lycopene to generate 7,7',9,9'-tetra-cis-β-carotene, which had not been reported before. A new carotenoid 7,7',9,9'-tetra-cis-β-carotene, the beta cyclization product of prolycopene, was discovered. Compared with the bacterial-derived carotenoid synthesis pathway, there is higher specificity and greater efficiency of the carotenoid synthesis pathway in algae. This research experimentally confirmed that the conversion of phytoene to lycopene in D. salina was similar to that of plants and different from bacteria and provided a new possibility for the metabolic engineering of β-carotene. IMPORTANCE The synthesis mode of all trans-lycopene in bacteria and plants is clear, but there are still doubts in microalgae. Dunaliella is the organism with the highest β-carotene content, and plant-type and bacterial-type enzyme genes have been found in its carotenoid metabolism pathway. In this study, the entire plant-type enzyme gene was completely cloned into Escherichia coli, and high-efficiency expression was obtained, which proved that carotenoid synthesis of algae is similar to that of plants. In bacteria, CRT can directly catalyze 4-step continuous dehydrogenation to produce all trans-lycopene. In plants, four enzymes (PDS, ZISO, ZDS, and CRTISO) are involved in this process. Although a carotenoid synthetase similar to that of bacteria has been found in algae, it does not play a major role. This research reveals the evolutionary relationship of carotenoid metabolism in bacteria, algae, and plants and is of methodologically innovative significance for molecular evolution research.

GWAS resolves molecular mechanisms underlying natural variation for carotenoids in Cucurbita maxima Duchesne

Carotenoid levels and composition are essential nutraceutical traits in Cucurbita maxima influencing the fruit flesh and rind colors. In this study, Mr Fugly, Boston Marrow, Baby Green Hubbard, Chicago Warted Hubbard, Golden Hubbard, and Bush Buttercup of USA; Australian Butter (Australia); Marmellata and Marina di Chioggia of Italy contained the highest carotenoid content. EMMAX (Efficient Mixed-Model Association eXpedited) was employed for a Genome-wide association study (GWAS) to identify associated genomic regions underlying the regulation of carotenoids. Here, we profiled the contents of α-carotene, β-carotene, β-cryptoxanthin, lutein, and zeaxanthin from a diversity panel of C. maxima consisting of classical horticulture groups including buttercup, turban, banana, zapallito, hubbard, mammoth and australian. Lutein and β-carotene were the major carotenoids among C. maxima accessions. Furthermore, we used genotyping by sequencing to identify 12,996 single nucleotide polymorphisms (SNPs) that were used to resolve population structure with three primary clusters and their admixed genotypes. Our GWAS revealed several SNPs related to 289 genes involved in plastid biogenesis, protein ubiquitination, transcriptional regulation at the carotenoid biosynthesis level, fruit ripening, and regulation of carotenoid transport. Together, these results contribute to a better understanding of the molecular mechanisms of carotenoid biosynthesis in fruit flesh and would facilitate breeding for enhanced carotenoids in winter squashes.

The BCO2 Genotype and the Expression of BCO1, BCO2, LRAT, and TTPA Genes in the Adipose Tissue and Brain of Rabbits Fed a Diet with Marigold Flower Extract.

This study was undertaken to evaluate the effect of the BCO2 genotype and dietary supplementation with marigold flower extract on the expression of BCO1, BCO2, LRAT, and TTPA genes in the adipose tissue and brain of rabbits. The concentrations of lutein, zeaxanthin, β-carotene, retinol, and α-tocopherol were determined in samples collected from rabbits. Sixty young male Termond White rabbits were allocated to three groups based on their genotype at codon 248 of the BCO2 gene (ins/ins, ins/del, and del/del). Each group comprised two subgroups; one subgroup was administered a standard diet, whereas the diet offered to the other subgroup was supplemented with 6 g/kg of marigold flower extract. The study demonstrated that the BCO2 genotype may influence the expression levels of the BCO2, LRAT, and TTPA genes in adipose tissue, and TTPA and BCO1 genes in the brain. Moreover, an increase in the amount of lutein in the diet of BCO2 del/del rabbits may increase the expression of BCO1, LRAT, and TTPA genes in adipose tissue, and the expression of the BCO2 gene in the brain. Another finding of the study is that the content of carotenoids and α-tocopherol increases in both the adipose tissue and brain of BCO2 del/del rabbits.