Antioxidant phytochemicals and antioxidant capacity of biofortified carrots (Daucus carota L.) of various colors

(1)H NMR-Based Metabolomics Reveals a Pedoclimatic Metabolic Imprinting in Ready-to-Drink Carrot Juices

Carrots are usually consumed in their native form or processed into many different products. Carrot juice is a popular beverage consumed throughout the world and is attracting increasing attention due to its nutritional value, being a natural source of bioactive compounds. Ready-to-drink carrot juices produced in the same factory were analyzed by (1)H nuclear magnetic resonance (NMR) spectroscopy. The juices were made from carrot roots of the same cultivar grown in three different geographical areas in Italy. More than 30 compounds have been identified and quantified, and the data was subjected to univariate ANOVA and multivariate analyses. Clear geographical-dependent clustering was observed, and the metabolic profiles were related to the different pedoclimatic conditions. The proposed phytoprofiling approach could be employed on an industrial scale to evaluate finished products involving different sites of supply of the raw material, thus improving both the quality and uniformity of the juices.

Ethnopharmacological survey on medicinal plants used in herbal drinks among the traditional communities of Pakistan

ETHNOPHARMACOLOGICAL RELEVANCE

There is very limited information regarding medicinal plants used by traditional healers in Pakistan, for treating wide-ranging diseases. Current study provides significant ethnopharmacological information, both qualitative and quantitative on medical plants in Pakistan and the pharmacological importance of herbal drinks, especially in the discovery of new drugs.

MATERIALS AND METHODS

The current ethnomedicinal field study was conducted from various traditional communities of Pakistan to document usage of medicinal plants as herbal drinks. Data was collected through field interviews from local people and using semi-structured questionnaires. Data was analyzed using quantitative indices such as UV (use value), RFC (Relative frequency of citation), and FL (Fidelity level).

RESULTS

The present study recorded 217 plant species belonging to 174 genera and 69 families used in herbal drinks preparations. Major herbal preparations include decoctions, infusions and juice. According to use reports, significant species were Aloe vera, Artemisia fragrans, Allium cepa, Senegalia catechu, Alternanthera sessilis, Malva ludwigii, Arnebia benthamii, Cichorium intybus, Coccinia grandis, Dalbergia sissoo. Major ailment treated with herbal drinks include heartburn, fever, diarrhea, hypertension, and others. Use value (UV) varies from 0.23 to 0.02, with Mentha arvensis (0.23) having the highest value of UV followed by Mentha longifolia (0.22), Plantago lanceolate (0.19), Achillea millefolium (0.18), Coriandrum sativum (0.18), Justicia adhatoda and Malva sylvestris (0.17). Values of RFC varies from 0.28 to 0.09 while Fidelity level (FL) among plants varies from 37.5 to 100. Alternanthera sessilis, Oxytropis lapponica, Millettia pinnata and Salvia bucharica had the highest FL value (100).

CONCLUSION

The use of medicinal plants is prevalent in traditional communities of Pakistan. Different herbal preparations are in common practice including various herbal drinks a common tradition and much favoured herbal preparation in terms of its results and regarded as reciprocal to modern drugs. Therefore, suggesting further pharmacological, phytochemical evaluation for essential metabolites and chemical constituents.

Breeding Vegetables with Increased Content in Bioactive Phenolic Acids

Vegetables represent a major source of phenolic acids, powerful antioxidants characterized by an organic carboxylic acid function and which present multiple properties beneficial for human health. In consequence, developing new varieties with enhanced content in phenolic acids is an increasingly important breeding objective. Major phenolic acids present in vegetables are derivatives of cinnamic acid and to a lesser extent of benzoic acid. A large diversity in phenolic acids content has been found among cultivars and wild relatives of many vegetable crops. Identification of sources of variation for phenolic acids content can be accomplished by screening germplasm collections, but also through morphological characteristics and origin, as well as by evaluating mutations in key genes. Gene action estimates together with relatively high values for heritability indicate that selection for enhanced phenolic acids content will be efficient. Modern genomics and biotechnological strategies, such as QTL detection, candidate genes approaches and genetic transformation, are powerful tools for identification of genomic regions and genes with a key role in accumulation of phenolic acids in vegetables. However, genetically increasing the content in phenolic acids may also affect other traits important for the success of a variety. We anticipate that the combination of conventional and modern strategies will facilitate the development of a new generation of vegetable varieties with enhanced content in phenolic acids.

Maize genotype and food matrix affect the provitamin A carotenoid bioefficacy from staple and carrot-fortified feeds in Mongolian gerbils (Meriones unguiculatus)

Biofortification to increase provitamin A carotenoids is an agronomic approach to alleviate vitamin A deficiency. Two studies compared biofortified foods using in vitro and in vivo methods. Study 1 screened maize genotypes (n = 44) using in vitro analysis, which demonstrated decreasing micellarization with increasing provitamin A. Thereafter, seven 50% biofortified maize feeds that hypothesized a one-to-one equivalency between β-cryptoxanthin and β-carotene were fed to Mongolian gerbils. Total liver retinol differed among the maize groups (P = 0.0043). Study 2 assessed provitamin A bioefficacy from 0.5% high-carotene carrots added to 60% staple-food feeds, followed by in vitro screening. Liver retinol was highest in the potato and banana groups, maize group retinol did not differ from baseline, and all treatments differed from control (P < 0.0001). In conclusion, β-cryptoxanthin and β-carotene have similar bioefficacy; meal matrix effects influence provitamin A absorption from carrot; and in vitro micellarization does not predict bioefficacy.

An outlook on chlorogenic acids-occurrence, chemistry, technology, and biological activities

Phenolics are widespread dietary antioxidants. Among these, chlorogenic acids (CGAs) received considerable attention for their wide distribution and part of human diet with potential biological effects. CGAs (71 compounds), being esters of derivatives of cinnamic acids with quinic acid are widely distributed in plant materials. Coffee is among the highest found in plants, ranging from 4 to 14%. Besides, these are reported in plant foods such as apples, pears, carrot, tomato, sweet potato, Phyllostachys edulis, oilseeds, Prunus domestica L, cherries, and eggplant. The traditional Chinese medicinal plants such as flowers and buds of Lonicera japonica Thunb and the leaves of Eucommia ulmodies contained CGAs as bioactive compound. These play an important role in the formation of roasted coffee flavor and have a marked influence on coffee cup quality. CGAs are considered as main precursors of coffee flavor and pigments. Recent technological advancements in the separation and purification of CGAs such as molecular-imprinted polymer technique; microwave-assisted extraction; pH gradient counter current chromatography has also been described. The consumption of coffee correlated to several health benefits such as reducing the risk of human chronic diseases such as inflammation, diabetes, and cardiovascular disease owing to its antioxidant potential.

An eco-metabolomic study of host plant resistance to Western flower thrips in cultivated, biofortified and wild carrots

Domestication of plants and selection for agronomic traits may reduce plant secondary defence metabolites relative to their ancestors. Carrot (Daucus carota L.) is an economically important vegetable. Recently, carrot was developed as a functional food with additional health-promoting functions. Biofortified carrots contain increased concentrations of chlorogenic acid as an antioxidant. Chlorogenic acid is involved in host plant resistance to Western Flower Thrips (Frankliniella occidentalis), one of the key agri- and horticultural pests worldwide. The objective of this study was to investigate quantitative host plant resistance to thrips in carrot and to identify candidate compounds for constitutive resistance. As such we explored whether cultivated carrot is more vulnerable to herbivore attack compared to wild carrot. We subjected a set of 14 biofortified, cultivated and wild carrot genotypes to thrips infestation. We compared morphological traits and leaf metabolic profiles of the three most resistant and susceptible carrots using nuclear magnetic resonance spectroscopy (NMR). In contrast to our expectation, wild carrots were not more resistant to thrips than cultivated ones. The most thrips resistant carrot was the cultivar Ingot which is known to be tolerant against carrot root fly (Psila rosae). Biofortified carrots were not resistant to thrips. Plant size, leaf area and number of leaf hairs did not differ between resistant and susceptible carrots. The metabolic profiles of the leaves of resistant carrots were significantly different from those of susceptible carrots. The leaves of resistant carrots contained higher amounts of the flavanoid luteolin, the phenylpropanoid sinapic acid and the amino acid β-alanine. The negative effect of these compounds on thrips was confirmed using in-vitro bioassays. Our results have potential implications for carrot breeders. The natural variation of metabolites present in cultivated carrots can be used for improvement of thrips resistance. This is especially promising in view of the candidate compounds we identified since they do not only confer a negative effect on thrips but as antioxidants also play an important role in the improvement of human health.

Extracts from black carrot tissue culture as potent anticancer agents

Black carrots contain anthocyanins possessing enhanced physiological activities. Explants of young black carrot shoots were cultured in Murashige and Skoog (MS) medium for callus initiation and were transferred to new MS medium supplemented with four different combinations of 2,4-dichlorophenoxyacetic acid and kinetin. Subsequently, the lyophilized calli and black carrot harvested from fields were subjected to ultrasound extraction with ethanol at a ratio of 1:15 (w:v). Obtained extracts were applied to various human cancer cell lines including MCF-7 SK-BR-3 and MDA-MB-231 (human breast adenocarcinomas), HT-29 (human colon adenocarcinoma), PC-3 (human prostate adenocarcinoma), Neuro 2A (Musmusculus neuroblastoma) cancer cell lines and VERO (African green monkey kidney) normal cell line by MTT assay. The highest cytotoxic activity was achieved against Neuro-2A cell lines exhibiting viability of 38-46% at 6.25 μg/ml concentration for all calli and natural extracts. However, a significantly high IC50 value of 170.13 μg/ml was attained in normal cell line VERO indicating that its natural counterpart is an ideal candidate for treatment of brain cancer without causing negative effects to normal healthy cells.

The content of phenolic compounds and radical scavenging activity varies with carrot origin and root color

The contents of phenolic compounds and radical scavenging activities were assessed in a carrot collection comprising 35 cultivars, landraces and breeding populations. The accessions originated from various world regions and they represented Eastern and Western carrot gene pools. In two-year field trial carrot roots of orange, red, yellow, white and purple color were cultivated, freeze-dried and analyzed for phenolic content by Folin-Ciocalteu assay and UV/Vis assay. Radical scavenging activity in the extracts was determined with a stable DPPH radical. Carrots developing purple roots possessed on average 9 times more phenolics than roots of other colors. Furthermore, they were rich in anthocyanins that caused very high antiradical activity. Red carrots showed higher antioxidant activity than orange, yellow and white carrots and in the season of lower rainfall they accumulated higher amounts of phenolic compounds. Carrots of Asian origin belonging to Eastern gene pool were more often purple or red and richer in phenolics and had higher antiradical activity than those from the Western gene pool with mainly orange roots.

Quantitative Raman spectroscopy for the analysis of carrot bioactives

Rapid quantitative near-infrared Fourier transform Raman analyses of the key phytonutrients in carrots, polyacetylenes and carotenoids, are reported here for the first time. Solvent extracts of 31 carrot lines were analyzed for these phytonutrients by conventional methods, polyacetylenes by GC-FID and carotenoids by visible spectrophotometry. Carotenoid concentrations were 0-5586 μg g(-1) dry weight (DW). Polyacetylene concentrations were 74-4846 μg g(-1) DW, highest in wild carrots. The polyacetylenes were falcarinol, 6-1237 μg g(-1) DW; falcarindiol, 42-3475 μg g(-1) DW; and falcarindiol 3-acetate, 27-649 μg g(-1) DW. Strong Raman bands for carotenoids gave good correlation to results by visible spectrophotometry. A chemometric model capable of quantitating carotenoids from Raman data was developed. A classification model for rapidly distinguishing carrots with high and low polyacetylene (limit of detection = 1400 μg g(-1)) concentrations based on Raman spectral intensity in the region of 2250 cm(-1) was produced.

Ultraviolet-B light treatment increases antioxidant capacity of carrot products

BACKGROUND

The effect of ultraviolet-B (UV-B) light as a postharvest treatment to enhance the antioxidant content of carrots and fresh-cut carrot products was evaluated. Four levels of UV-B dose ranging from 1.3 to 12 kJ m⁻² were applied to whole, baby and various styles of cut carrots, and the changes in antioxidant capacity, total soluble phenolics and phenylalanine ammonia-lyase (PAL, EC 4.3.1.24) activity were measured after a 3 day incubation period at 15 °C and 45% relative humidity.

RESULTS

Both cutting style and dose level were factors in determining carrot responses to UV-B treatment. Antioxidant capacity increased significantly (1.4-6.6-fold). Total soluble phenolic results correlated directly with those of antioxidant capacity (R² = 0.953), indicating that the enhancements achieved were due to an increase in phenolic content. High-performance liquid chromatography analysis revealed that 5-O-caffeoylquinic acid (5-CQA) was the primary phenolic responsible for this increase. Higher PAL activity was also observed in UV-B-treated samples, indicating that the increase in 5-CQA was a biological response to UV-B exposure.

CONCLUSION

UV-B treatment has the potential to increase the nutritional value of carrots and offers an exciting opportunity to increase consumer accessibility to dietary choices that are rich in antioxidants.

Potential risks resulting from fruit/vegetable-drug interactions: effects on drug-metabolizing enzymes and drug transporters

It has been well established that complex mixtures of phytochemicals in fruits and vegetables can be beneficial for human health. Moreover, it is becoming increasingly apparent that phytochemicals can influence the pharmacological activity of drugs by modifying their absorption characteristics through interactions with drug transporters as well as drug-metabolizing enzyme systems. Such effects are more likely to occur in the intestine and liver, where high concentrations of phytochemicals may occur. Alterations in cytochrome P450 and other enzyme activities may influence the fate of drugs subject to extensive first-pass metabolism. Although numerous studies of nutrient-drug interactions have been published and systematic reviews and meta-analyses of these studies are available, no generalizations on the effect of nutrient-drug interactions on drug bioavailability are currently available. Several publications have highlighted the unintended consequences of the combined use of nutrients and drugs. Many phytochemicals have been shown to have pharmacokinetic interactions with drugs. The present review is limited to commonly consumed fruits and vegetables with significant beneficial effects as nutrients and components in folk medicine. Here, we discuss the phytochemistry and pharmacokinetic interactions of the following fruit and vegetables: grapefruit, orange, tangerine, grapes, cranberry, pomegranate, mango, guava, black raspberry, black mulberry, apple, broccoli, cauliflower, watercress, spinach, tomato, carrot, and avocado. We conclude that our knowledge of the potential risk of nutrient-drug interactions is still limited. Therefore, efforts to elucidate potential risks resulting from food-drug interactions should be intensified in order to prevent undesired and harmful clinical consequences.

Binding of polyphenols to plant cell wall analogues - Part 2: Phenolic acids

Bacterial cellulose and cellulose-pectin composites were used as well-defined model plant cell wall (PCW) systems to study the interaction between phenolic acids (PA) derived from purple carrot juice concentrate (PCJC) and PCW components. Significant PA depletion from solution occurred, with pure cellulose initially (30s-1h) absorbing more than cellulose-pectin composites in the first hour (ca 20% cf 10-15%), but with all composites absorbing similar levels (ca 30%) after several days. Individual PAs bound to different relative extents with caffeic acid>chlorogenic acid>ferulic acid. Extrapolation of data for these model systems to carrot puree suggests that nutritionally-significant amounts of PAs could bind to cell walls, potentially restricting bioavailability in the small intestine and, as a consequence, delivering PAs to the large intestine for fermentation and metabolism by gut bacteria.

Effects of a carrot juice intervention on plasma carotenoids, oxidative stress, and inflammation in overweight breast cancer survivors

Evidence suggests that higher plasma carotenoid concentrations are protective in relation to breast cancer recurrence. This simple randomized carrot juice intervention study was designed to test the hypothesis that daily intake of 8 ounces of fresh BetaSweet (anthocyanin-rich) or Balero orange carrot juice would increase plasma total carotenoid concentrations to levels previously shown to be associated with reduced breast cancer recurrence. It was hypothesized that regular carrot juice intake would be associated with reductions in oxidative stress (8-iso-PGF2α) and inflammation (thromboxane B2, prostaglandin E2 metabolites, and hsC-reactive protein). Sixty-nine overweight breast cancer survivors consumed fresh carrot juice made from study-provided carrots for 3 wk. Total plasma carotenoids increased by 1.65 and 1.38 umol/L for the BetaSweet and Balero carrot juice, respectively. Rise in total plasma carotenoids for the overall sample was inversely associated with 8-iso-PGFα (OR: 0.13; 95% CI: 0.20 to 0.75; no differences were shown by carrot variety. These results suggest daily intake of fresh carrot juice is a simple and effective approach to increasing plasma total carotenoids and in turn reducing oxidative stress, but not inflammatory markers, in women previously treated for breast cancer.

Phenolics content and antioxidant activity of tartary buckwheat from different locations

Two tartary buckwheat samples (Xingku No.2 and Diqing) grown at three locations were analyzed for free and bound phenolic content and antioxidant properties. Moreover, the relative contributions of variety and growing environment to phenolic content and antioxidant properties were determined, as well as correlations of these properties to growing conditions. The total phenolic contents varied from 5,150 to 9,660 μmol of gallic acid equivalents per 100 gram of dry weight (DW) of tartary buckwheat and the free phenolics accounted for 94% to 99%. Rutin content was in the range from 518.54 to 1,447.87 mg per 100 gram of DW of tartary buckwheat. p-Hydroxybenzoic, ferulic and protocatechuic acids were the prominent phenolic acids and other phenolics, including p-coumaric, gallic, caffeic, vanillic and syringic acids were also detected. Tartary buckwheat exhibited higher DPPH· and ABTS·+ scavenging activities and was more effective at preventing the bleaching of β-carotene in comparison with reference antioxidant and plant phenolics constituents. Additionally, growing conditions and the interaction between variety and environment may have more contribution than variety to individual phenolics and antioxidant properties of tartary buckwheat. Environmental parameters such as higher altitudes may also have an increasing effect on rutin and phenolic acids. This study suggests that tartary buckwheat has potential health benefits because of its high phenolic content and antioxidant properties. These components could also be enhanced by optimizing the growing conditions of a selected variety.

Impact of boron, calcium and genetic factors on vitamin C, carotenoids, phenolic acids, anthocyanins and antioxidant capacity of carrots (Daucus carota)

Carrots (Daucus carota L.) were used to investigate the effects and interactions of cultivar and mineral supply on the nutritional quality (antioxidant potential, vitamin C, carotenoids and phenolic acids) of the resulting storage roots. The supplement of boron (B) and or calcium (Ca) in the feeding solutions, during plant growth, influenced the accumulation of other minerals, such as P, K, Mg, S and Na, in the storage roots (p<0.05). When no additional B or Ca was supplied (e.g. -B or -Ca treatment), we observed 33-50% increase in the accumulated levels of α- and β-carotenes, and 45-70% increase of vitamin C. Carrots grown with no supplement of B in the nutrient solutions (e.g. -B treatment and -ve control) had significantly higher (p<0.001) levels of total phenolic acids compared to the carrots with the supplement of B (e.g. -Ca treatment and +ve control). A strong positive correlation was observed between the total phenolic contents and ORAC values (r=0.932) in all the cultivars. The results suggest that both cultivar and mineral supply were major determinants of nutritional quality of the carrots. The nutritional value of carrot crops (with an acceptable physical quality) can be enhanced by manipulating mineral nutrient applications.

Metabolic fingerprinting reveals differences between shoots of wild and cultivated carrot (Daucus carota L.) and suggests maternal inheritance or wild trait dominance in hybrids

Differences between the metabolic content of cultivars and their related wild species not only have implications for breeding and food quality, but also for the increasingly studied area of crop to wild introgression. Wild and cultivated western carrots belong to the same outcrossing species and hybridize under natural conditions. The metabolic fingerprinting of Dutch wild carrot and of western orange carrot cultivar shoots using (1)H NMR showed only quantitative differences in chemical content, indicating relatively low divergence after domestication. Main differences reside in the primary metabolite content and in the concentrations of chlorogenic acid and feruloyl quinic acid in the shoots of the different carrot types. Wild×cultivar hybrids cannot be distinguished from wild plants based on the metabolome, suggesting maternal, maternal environment, or dominance effects, and indicating high hybrid fitness in wild conditions. Considering these similarities, introgression is a real possibility in carrots, but understanding its consequences would require further studies using backcrosses in a multiple environments.

Carotenoid biosynthesis genes provide evidence of geographical subdivision and extensive linkage disequilibrium in the carrot

According to the history of the cultivated carrot, root colour can be considered as a structural factor of carrot germplasm. Therefore, molecular variations of carotenoid biosynthesis genes, these being involved in colour traits, represent a good putative source of polymorphism related to diversity structure. Seven candidate genes involved in the carotenoid biosynthesis pathway have been analysed from a sample of 48 individual plants, each one from a different cultivar of carrot (Daucus carota L. ssp. sativus). The cultivars were chosen to represent a large diversity and a wide range of root colour. A high single nucleotide polymorphism (SNP) frequency of 1 SNP per 22 bp (mean pi (sil) = 0.020) was found on average within these genes. The analysis of genetic structure from carotenoid biosynthesis gene sequences and 17 putatively neutral microsatellites showed moderate genetic differentiation between cultivars originating from the West and the East (F (ST) = 0.072), this being consistent with breeding history, but not previously evidenced by molecular tools. Surprisingly, carotenoid biosynthesis genes did not exhibit decay of LD (mean r (2) = 0.635) within the 700-1,000 bp analysed, even though a fast decay level of LD is expected in outcrossing species. The high level of intralocus LD found for carotenoid biosynthesis genes implies that candidate-gene association mapping for carrot root colour should be useful to validate gene function, but may be unable to identify precisely the causative variations involved in trait determinism. Finally this study affords the first molecular evidence of a genetic structure in cultivated carrot germplasm related to phylogeography.

Comparison of purple carrot juice and β-carotene in a high-carbohydrate, high-fat diet-fed rat model of the metabolic syndrome

Anthocyanins, phenolic acids and carotenoids are the predominant phytochemicals present in purple carrots. These phytochemicals could be useful in treatment of the metabolic syndrome since anthocyanins improve dyslipidaemia, glucose tolerance, hypertension and insulin resistance; the phenolic acids may also protect against CVD and β-carotene may protect against oxidative processes. In the present study, we have compared the ability of purple carrot juice and β-carotene to reverse the structural and functional changes in rats fed a high-carbohydrate, high-fat diet as a model of the metabolic syndrome induced by diet. Cardiac structure and function were defined by histology, echocardiography and in isolated hearts and blood vessels; liver structure and function, oxidative stress and inflammation were defined by histology and plasma markers. High-carbohydrate, high-fat diet-fed rats developed hypertension, cardiac fibrosis, increased cardiac stiffness, endothelial dysfunction, impaired glucose tolerance, increased abdominal fat deposition, altered plasma lipid profile, liver fibrosis and increased plasma liver enzymes together with increased plasma markers of oxidative stress and inflammation as well as increased inflammatory cell infiltration. Purple carrot juice attenuated or reversed all changes while β-carotene did not reduce oxidative stress, cardiac stiffness or hepatic fat deposition. As the juice itself contained low concentrations of carotenoids, it is likely that the anthocyanins are responsible for the antioxidant and anti-inflammatory properties of purple carrot juice to improve glucose tolerance as well as cardiovascular and hepatic structure and function.

Anthocyanins in purple-orange carrots (Daucus carota L.) do not influence the bioavailability of beta-carotene in young women

Purple carrots contain anthocyanins in addition to the provitamin A carotenoids in typical orange carrots. Simultaneous consumption of these phytochemicals in carrots may affect the bioavailability of carotenoids. The bioavailability of beta-carotene in humans was assessed from an acute feeding of orange (OC) and purple (PC) carrots with white (WC) as a control. Carrot smoothies were served to female subjects (n = 5, aged 21-26 years) for breakfast after 1 week on a low carotenoid diet and overnight fast. OC and PC smoothies were equalized to 10.3 mg of all-trans beta-carotene. Plasma beta-carotene was measured for 144 h following treatments. Peak plasma concentrations of OC and PC treatments did not differ. The PC treatment 0-144 h area-under-the-curve for beta-carotene was 76% of the OC treatment (P < 0.05). However, when the first 24 h were compared, OC and PC treatments did not differ, suggesting that anthocyanins in purple carrots do not affect the absorption of beta-carotene postprandially.

Serum α- and β-Carotene Concentrations Qualitatively Respond to Sustained Carrot Feeding

β-Carotene is a predominant source of vitamin A in developing countries. Genetically selected “high carotene” carrots could have an impact on the vitamin A and antioxidant status of people if widely adopted. A 3 × 3 crossover study in humans ( n = 10) evaluated the difference in uptake and clearance of α- and β-carotene from carrots genetically selected and traditionally bred to have high, typical, or no carotene. Subjects were fed white (0 mg α- and β-carotene/d), orange (1.8 mg α-carotene and 2.6 mg β-carotene/d), or dark-orange (4 mg α-carotene and 7 mg β-carotene/d) carrots in muffins for 11 d, with a 10-d washout phase between treatments. Serum carotenoid and retinol concentrations were measured by HPLC. C-reactive protein (CRP), an indicator of underlying inflammation or infection which may lower serum retinol, was measured at the beginning of each period. A significant treatment effect occurred for serum α- and β-carotene concentrations ( P < 0.001), and a trend towards a negative effect of subjects’ BMI on concentrations ( P= 0.08). A significant treatment by sequence interaction was observed ( P = 0.038), which was attributable to a difference in serum α- and β-carotene concentrations between carrot treatments in the first period. Serum retinol remained stable for the first 20 d of the intervention and then decreased ( P = 0.02). CRP was not elevated in any subject. High carotene carrots provide more provitamin A carotenoids than the typical store-bought variety, without a change in flavor. The availability of high carotene carrots could readily increase consumption of β-carotene and potentially impact the vitamin A status of those individuals who are deficient or at risk of depletion.