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1.
Epidemiological data have shown a link between dietary intake of tomatoes and tomato products (rich in carotenoids) and a decreased risk of chronic diseases. The carotenoid profile in tomato products depends on tomato variety as well as the thermal conditions used in processing. The final carotenoid profile may affect the bioaccessibility and bioavailability of these biomolecules. Therefore, nondestructive, reliable methods are needed to characterize the structural and stereochemical variation of carotenoids. CDCl(3) rapid extraction was used to extract carotenoids from tomato juice as an alternative rapid procedure that minimizes solvents and time consumption prior to NMR analysis. The profile of these biomolecules was characterized by application of high-resolution multidimensional NMR techniques using a cryogenic probe. The combination of homonuclear and heteronuclear two-dimensional NMR techniques served to identify (all-E)-, (5Z)-, (9Z)-, and (13Z)-lycopene isomers and other carotenoids such as (all-E)-beta-carotene and (15Z)-phytoene dissolved in the extracted lipid mixture. The use of one-dimensional NMR enabled the rapid identification of lycopene isomers, thereby minimizing further isomerization of (all-E)-lycopene as compared to HPLC data. On the basis of the assignments accomplished, the carotenoid profile of typical tomato juice was successfully determined with minimal purification procedures.  相似文献   

2.
Several studies have implicated the potent antioxidant properties of lycopene. However, most of the studies used only the (all-E)-isomer. (Z)-Isomers of lycopene were found in substantial amounts in processed foods and in human tissues. In the present study, we investigated in vitro the antioxidant activity of (5Z)-, (9Z)-, and (13Z)-lycopene compared to the (all-E)-isomer. Additionally, prolycopene, the (7Z,9Z,7'Z,9'Z)-isomer found in tangerine tomatoes, was analyzed. No significant differences were found between the isomers in ferric reducing antioxidant power assay and in bleaching the radical cation of 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), both based on ET mechanisms. In contrast, scavenging activity against peroxyl radicals generated by thermal degradation of 2,2'-azobis(2-amidinopropane) (AAPH) was higher in the (Z)-isomers. (5Z)-Lycopene was most antioxidant in scavenging lipid peroxyl radicals, evaluated by analyzing the inhibition of MbFe(III) lipid peroxidation of linoleic acid in mildly acidic conditions (pH 5.8) in a micellar environment, modeling a possible antioxidant action in the gastric compartment.  相似文献   

3.
Papaya (Carica papaya L.) F1 hybrids and inbred lines grown in Costa Rica were screened for morphological and nutritionally relevant fruit traits. The qualitative composition of carotenoids showed great similarity, being mostly composed of free and esterified β-cryptoxanthins accompanied by β-carotene, lycopene, and biosynthetic precursors. High levels of (all-E)-lycopene and its isomers were distinctive for red-fleshed hybrids, whereas yellow-fleshed fruits were virtually devoid of lycopenes. Because carotenoid levels among the investigated hybrids and lines differed significantly, this study supports the hypothesis of an exploitable genetic variability, and a potential heterotic effect regarding carotenoid expression may be instrumental in papaya-breeding programs. Due to significantly higher levels of provitamin A carotenoids and coinciding high levels of total lycopene, particularly red-fleshed hybrids might represent prospective sources of these compounds. Furthermore, the nutritional value of some genotypes was boosted by substantial amounts of ascorbic acid (up to 73 mg/100 g of fresh weight), which correlated to total soluble solids (R(2) = 0.86).  相似文献   

4.
Sixteen carotenoids were isolated from the flesh of Brazilian red guavas (Psidium guajava L.). Their structures were established by means of UV-visible, 400 and 500 MHz (1)H NMR, 120 and 125 MHz (13)C NMR, mass, and circular dichroism spectra. The carotenoids were identified as phytofluene, (all-E)-, (9Z)-, (13Z)-, and (15Z)-beta-carotene, (all-E)-gamma-carotene, (all-E)-, (9Z)-, (13Z)-, and (15Z)-lycopene, (all-E,3R)-beta-cryptoxanthin, (all-E, 3R)-rubixanthin, (all-E,3S,5R,8S)-cryptoflavin, (all-E,3R,3'R, 6'R)-lutein, (all-E,3S,5R,6R,3'S,5'R,8'R)-, and (all-E,3S,5R,6R,3'S, 5'R,8'S)-neochrome. Thirteen of the carotenoids identified are reported as guava carotenoids for the first time.  相似文献   

5.
Samples of catsup from 13 commercial sources, representing at least 10 U.S. manufacturers, were analyzed for carotenoid content, antioxidant activity, and percentage solids. The solids content of these catsup brand samples varied from 26.31 to 38.06% solids. The lycopene content ranged from 59.42 to 183.36 microg, and total carotenoids were as high as 216.6 microg/g fresh weight, respectively. In addition, both hydrophilic and lipophilic antioxidant activities were measured using the Trolox equivalent antioxidant capacity (TEAC) assay. These measurements of samples of the various catsup brands ranged from 176.5 to 356.8 total TEAC units.  相似文献   

6.
The structures of biosynthetic deuterated carotenoids in labeled vegetables were investigated: (all-E)-lutein and (all-E)-beta-carotene from spinach, and (all-E)-beta-carotene and (all-E)-alpha-carotene from carrots. The vegetables were grown hydroponically using a nutrient solution enriched with deuterium oxide (D(2)O) and were extracted using matrix solid-phase dispersion (MSPD). Deuterium enrichment in the carotenoid molecules was determined by liquid chromatography-mass spectrometry (LC-MS). (all-E)-Lutein and (all-E)-beta-carotene in spinach showed partial deuteration from (2)H(1) to (2)H(12), with the abundance maximum at (2)H(5). (all-E)-beta-Carotene and (all-E)-alpha-carotene from carrots showed partial deuteration from (2)H(1) to (2)H(17), with the abundance maximum at (2)H(11). The (1)H NMR spectra of the four deuterated carotenoids showed additional signals for all methyl groups and decreased signal intensity for the olefinic protons and the methylene protons in the ring. These differences are due to isotopic effects and are based on the substitution of protons by deuterium atoms. The deuteration was distributed randomly throughout the carotenoid molecules.  相似文献   

7.
Waxy corns are becoming increasingly consumed as fresh foods or as raw materials for whole grain foods facilitating human consumption in China, so they are usually harvested before complete maturity. Unfortunately, information on functional properties of immature waxy corns is very limited. Therefore, we investigated the profiles of carotenoids, anthocyanins, phenolics, and the antioxidant activity in three types of waxy corn with different colors (white, yellow, and black) during maturation, as well as a normal corn (yellow) used as control. The results showed that black waxy corn had the highest quantity of anthocyanins, phenolics and the best antioxidant activity, yellow corn contained a relatively large amount of carotenoids, while white corn had the lowest amounts of carotenoids, anthocyanins, phenolics, and antioxidant capacity. For each type of waxy corn, the higher carotenoids were found at the M2 stage (no major difference between the M1 and M2 stages for yellow corn). The levels of anthocyanin and phenolics decreased for white and yellow corns, contrary to those for black corn during maturation. The antioxidant activity determined by scavenging 2,2-diphenyl-1-picrylhydrazyl (DPPH), the ferric reducing antioxidant power (FRAP), and the Trolox equivalent antioxidant capacity (TEAC) assays increased with ripening, but no difference was found between the M2 and maturity stages for yellow and black corns. For white corn, the DPPH radical scavenging activity first increased and then decreased, while the antioxidant activity determined by TEAC and FRAP assay decreased during maturation. Differences in these parameters indicate that types and harvesting time have significant influences on functional properties of waxy corns.  相似文献   

8.
Quantitative data with regard to dietary (3R,3'R,6'R)-lutein, (3R,3'R)-zeaxanthin, and their (E/Z)-geometrical isomers are scarce, and in most cases, only the combined concentrations of these two carotenoids in foods are reported. Lutein and zeaxanthin accumulate in the human macula and have been implicated in the prevention of age-related macular degeneration (AMD). The qualitative and quantitative distributions of lutein, zeaxanthin, and their (E/Z)-isomers in the extracts from some of the most commonly consumed fruits, vegetables, and pasta products were determined by HPLC employing a silica-based nitrile-bonded column. Green vegetables had the highest concentration of lutein (L) and zeaxanthin (Z), and the ratios of these carotenoids (L/Z) were in the range 12-63. The yellow-orange fruits and vegetables, with the exception of squash (butternut variety), had much lower levels of lutein in comparison to greens but contained a higher concentration of zeaxanthin. The ratio of lutein to zeaxanthin (L/Z) in two North American bread varieties of wheat (Pioneer, Catoctin) was 11 and 7.6, respectively, while in a green-harvested wheat (Freekeh) imported from Australia, the ratio was 2.5. Between the two pasta products examined, lasagne and egg noodles, the latter had a much higher concentration of lutein and zeaxanthin. The levels of the (E/Z)-geometrical isomers of lutein and zeaxanthin in these foods were also determined.  相似文献   

9.
Sorghum is a critical source of food in the semiarid regions of sub-Saharan Africa and India and a potential source of dietary phytochemicals including carotenoids. The objective of this study was to determine the carotenoid profiles of sorghum cultivars, selected on the basis of their yellow-endosperm kernels, at various developmental stages. Following extraction from sorghum flours, carotenoids were separated by high-performance liquid chromatography (HPLC) with diode array detection. Total carotenoid content in fully matured yellow-endosperm sorghum kernels (0.112-0.315 mg/kg) was significantly lower (p < 0.05) than that in yellow maize (1.152 mg/kg) at physiological maturity. Variation in total carotenoids and within individual carotenoid species was observed in fully mature sorghum cultivars. For developing kernels, large increases in carotenoid content occurred between 10 and 30 days after half bloom (DAHB), resulting in a peak accumulation between 6.06 and 28.53 microg of total carotenoids per thousand kernels (TK). A significant (p < 0.05) decline was noted from 30 to 50 DAHB, resulting in a final carotenoid content of 2.62-15.02 microg/TK total carotenoids. (all-E)-Zeaxanthin was the most abundant carotenoid, ranging from 2.22 to 13.29 microg/TK at 30 DAHB. (all-E)-Beta-carotene was present in modest amounts (0.15-3.83 microg/TK). These data suggest the presence of genetic variation among sorghum cultivars for carotenoid accumulation in developing and mature kernels.  相似文献   

10.
Processing effects on lycopene content and antioxidant activity of tomatoes   总被引：8，自引：0，他引：8  
Consumption of tomato products has been associated with decreased risk of some cancer types, and the tomato antioxidant, lycopene, is thought to play an important role in the observed health effects. In this study, four carotenoids, trans-lycopene, phytofluene, phytoene, and zeta-carotene, were quantified in tomato products. Samples of raw tomatoes, tomato juice after hot break scalder, and final paste were obtained from two different processing plants over two years. Comparison of carotenoid levels throughout processing indicated that lycopene losses during processing of tomatoes into final paste (25-30 degrees Brix) ranged from 9 to 28%. The initial Brix level of the raw tomatoes appeared to influence the amount of lycopene loss that occurred, possibly due to the differences in processing time required to achieve the final desired Brix level of the paste. In general, no consistent changes in the other carotenoids were observed as a function of processing. The antioxidant activity of fresh tomatoes, tomato paste, and three fractions obtained from these products (i.e., aqueous, methanol, and hexane fractions) was also determined. In both a free radical quenching assay and a singlet oxygen quenching assay, significant antioxidant activity was found in both the hexane fraction (containing lycopene) and the methanol fraction, which contained the phenolic antioxidants caffeic and chlorogenic acid. The results suggest that in addition to lycopene, polyphenols in tomatoes may also be important in conferring protective antioxidative effects.  相似文献   

11.
The influence of thermal treatment and light exposure on degradation and isomerization of the predominant carotenoids (lutein and beta-carotene) occurring in green leafy vegetables was assessed. The effect of lipid addition on carotenoid stability was also evaluated. For the first time, the stabilities of pure carotenoids and chloroplast-bound carotenoids were compared. Besides degradation, heating caused carotenoid isomerization in all samples. Whereas pure carotenoids favor 13-cis isomers, in native chloroplasts and heated chloroplasts 9-cis isomers were predominant. Illumination of freshly prepared chloroplast isolates caused an initial increase in the level of lutein (9.6%) and beta-carotene (29.8%), while pure carotenoids exhibited time-dependent degradation. The addition of lipids to chloroplast preparations had the reverse effects on the retention of both carotenoids after heating; isomerization was not significantly affected. It was demonstrated that carotenoid stability has to be evaluated for every individual pigment in its genuine environment. Stability data based on model systems (e.g., pure carotenoids) may not be transferred to complex food matrices without intensive investigation.  相似文献   

12.
Tomato is the main dietary source of lycopene, a carotenoid that is known to have protective effects on health and whose metabolites could also be involved in bioactivity. Herein we present the first organic synthesis of two potentially bioactive lycopene metabolites, namely, 10'-apolycopen-10'-oic acid (6) and 14'-apolycopen-14'-oic acid (13), which were obtained in their (all-E) stereoisomeric forms using Wittig and Horner-Wadsworth-Emmons type coupling reactions. Both molecules are shown to up-regulate the carotenoid asymmetric cleavage enzyme BCO2 while having no effect on BCO1 expression.  相似文献   

13.
Epidemiological studies have consistently demonstrated that there is an association between carotenoid-rich food intakes with a low incidence in chronic diseases. Nevertheless, there is not an association between the intake of total dietary carotenoids and chronic health incidence in the European population, probably because of different carotenoid food sources and bioavailability. The objective of this study was to evaluate the small and large intestine bioaccessibilities of major dietary carotenoids from fruits and vegetables in a common diet. A bioaccessibility model that includes enzymatic digestion and in vitro colonic fermentation was employed. Lutein presented greater small intestine bioaccessibility (79%) than beta-carotene (27%) or lycopene (40%). With regard to large intestine bioaccessibility, similar amounts of lycopene and beta-carotene were released from the food matrix (57%), whereas small amounts of lutein (17%) were released. These results suggest that 91% of the beta-carotene, lutein, and lycopene contained in fruits and vegetables is available in the gut during the entire digestion process. Colonic fermentation is shown to be important for carotenoid availability in the gut.  相似文献   

14.
The aim of this study was to produce in vitro oxidation products of lycopene, which could be possible in vivo metabolites. An oxidation of lycopene with potassium permanganate gave a range of lycopene degradation compounds resulting from the oxidative cleavage of one or two carbon-carbon double bonds. Eleven apo-lycopenals/ones and six apo-carotendials were obtained and tentatively characterized by HPLC-DAD-MS. Apo-11-lycopenal and apo-8,6'-carotendial were isolated and characterized by (1)H NMR for the first time. Lycopene was submitted to an oxidation by atmospheric oxygen catalyzed by a metalloporphyrin, a model system of the active center of cytochrome P450 enzymes. (Z)-Isomers, monoxides, and cleavage compounds of (E)-lycopene were formed. We propose a mechanism of oxidation of lycopene by this system.  相似文献   

15.
Both microwave-assisted extraction (MAE) and ultrasound-assisted extraction (UAE) have been widely applied in the extraction of a variety of biologically active compounds including carotenoids due to their lower pollution to environment, high extraction efficiency, lower cost, and shorter extraction time as compared to conventional extraction techniques. However, there are few reports on their effects on the stability of these compounds. In the present study, the stability of (all-E)-astaxanthin, one of the carotenoids, was examined under the action of both ultrasound and microwave. Results showed that microwave induced the isomerization of (all-E)-astaxanthin to its Z analogues, preferentially to (13Z)-astaxanthin as analyzed by HPLC coupled with diode array detection and LC-MS; and the percentage of the isomerization increased with increasing both treatment time and microwave power. In contrast to the microwave, the ultrasound degraded (all-E)-astaxanthin to unidentified colorless compound(s) as suggested by HPLC analysis and UV/vis measurements, and the degradation likewise increased as both treatment time and ultrasonic power increased. The results presented here emphasized that both MAE and UAE techniques should be carefully used in the extraction of unstable compounds such as (all-E)-astaxanthin.  相似文献   

16.
Two pigmented wheat genotypes (blue and purple) and two black barley genotypes were fractionated in bran and flour fractions, examined, and compared for their free radical scavenging properties against 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt radical cation (Trolox equivalent antioxidant capacity, TEAC), ferric reducing antioxidant power (FRAP), total phenolic content (TPC), phenolic acid composition, carotenoid composition, and total anthocyanin content. The results showed that fractionation has a significant influence on the antioxidant properties, TPC, anthocyanin and carotenoid contents, and phenolic acid composition. Bran fractions had the greatest antioxidant activities (1.9-2.3 mmol TEAC/100 g) in all four grain genotypes and were 3-5-fold higher than the respective flour fractions (0.4-0.7 mmol TEAC/100 g). Ferulic acid was the predominant phenolic acid in wheat genotypes (bran fractions) while p-coumaric acid was the predominant phenolic acid in the bran fractions of barley genotypes. High-performance liquid chromatography analysis detected the presence of lutein and zeaxanthin in all fractions with different distribution patterns within the genotypes. The highest contents of anthocyanins were found in the middlings of black barley genotypes or in the shorts of blue and purple wheat. These data suggest the possibility to improve the antioxidant release from cereal-based food through selection of postharvest treatments.  相似文献   

17.
The present study aims first to compare the antioxidant microconstituent contents between organically and conventionally grown tomatoes and, second, to evaluate whether the consumption of purees made of these tomatoes can differently affect the plasma levels of antioxidant microconstituents in humans. When results were expressed as fresh matter, organic tomatoes had higher vitamin C, carotenoids, and polyphenol contents (except for chlorogenic acid) than conventional tomatoes. When results were expressed as dry matter, no significant difference was found for lycopene and naringenin. In tomato purees, no difference in carotenoid content was found between the two modes of culture, whereas the concentrations of vitamin C and polyphenols remained higher in purees made out of organic tomatoes. For the nutritional intervention, no significant difference (after 3 weeks of consumption of 96 g/day of tomato puree) was found between the two purees with regard to their ability to affect the plasma levels of the two major antioxidants, vitamin C and lycopene.  相似文献   

18.
Antioxidant activities of astaxanthin and related carotenoids   总被引：40，自引：0，他引：40  
The antioxidant activities of astaxanthin and related carotenoids have been measured by employing a newly developed fluorometric assay. This assay is based on 4,4-difluoro-3,5-bis(4-phenyl-1, 3-butadienyl)-4-bora-3a,4a-diaza-s-indacene (BODIPY 665/676) as an indicator; 2,2'-azobis-2,4-dimethylvaleronitrile (AMVN) as a peroxyl radical generator; and 6-hydroxy-2,5,7, 8-tetramethylchroman-2-carboxylic acid (Trolox) as a calibrator in an organic and liposomal media. By employing this assay, three categories of carotenoids were examined: namely, the hydrocarbon carotenoids lycopene, alpha-carotene, and beta-carotene; the hydroxy carotenoid lutein; and the alpha-hydroxy-ketocarotenoid astaxanthin. The relative peroxyl radical scavenging activities of Trolox, astaxanthin, alpha-tocopherol, lycopene, beta-carotene, lutein, and alpha-carotene in octane/butyronitrile (9:1, v/v) were determined to be 1.0, 1.0, 1.3, 0.5, 0.4, 0.3, and 0.2, respectively. In dioleoylphosphatidyl choline (DOPC) liposomal suspension in Tri-HCl buffer (pH 7.4 at 40 degrees C), the relative reactivities of astaxanthin, beta-carotene, alpha-tocopherol, and lutein were found to be 1.00, 0.9, 0.6, and 0.6, respectively. When BODIPY 665/676 was replaced by 4,4-difluoro-5-(4-phenyl-1,3-butadienyl)-4-bora-3a, 4a-diaza-s-indacene-3-undecanoic acid (BODIPY 581/591 C(11)) as an indicator, astaxanthin showed the highest antioxidant activity toward peroxyl radicals. The relative reactivities of Trolox, astaxanthin, alpha-tocopherol, alpha-carotene, lutein, beta-carotene, and lycopene were determined to be 1.0, 1.3, 0.9, 0.5, 0.4, 0.2, and 0.4, respectively.  相似文献   

19.
The lycopene content of 50 commercial cultivars of seeded and seedless red-fleshed watermelons was determined. Scanning colorimetric and spectrophotometric assays of total lycopene were used to separate watermelon cultivars into low (<50 mg/kg fw), average (50-70 mg/kg fw), high (70-90 mg/kg fw), and very high (>90 mg/kg fw). Cultivars varied greatly in lycopene content, ranging from 33 to 100 mg/kg. Most of the seeded hybrid cultivars had average lycopene contents. Sixteen of the 33 seedless types had lycopene contents in the high and very high ranges. All-trans-lycopene was the predominant carotenoid (84-97%) in all watermelon cultivars measured by high-performance liquid chromatography, but the germplasm differed in the relative amounts of cis-lycopene, beta-carotene, and phytofluene. Red-fleshed watermelon genotypes vary extensively in carotenoid content and offer opportunities for developing watermelons with specifically enhanced carotenoids.  相似文献   

20.
Botryococcus braunii is a green colonial microalga that is used mainly for the production of hydrocarbons, exopolysaccharides, and carotenoids. In the present study, the antioxidant properties of acetone extracts of B. braunii were evaluated using in vitro model systems such as 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydroxy radical scavenging, and lipid peroxidation in human low-density lipoprotein and rat tissues. Acetone extracts of B. braunii (equivalent to 10 ppm total carotenoid) exhibited 71 and 67% antioxidant activity in DPPH and hydroxyl radical scavenging model systems, respectively. Similarly, the extract also showed 72, 71, and 70% antioxidant activity in the liver, brain, and kidney of rats. Low-density lipoprotein oxidation induced by Cu2+ ions was also protected (22, 38, and 51%) by the algal extract in a dose-dependent manner (4, 6, and 8 ppm levels of total carotenoid). Thiobarbituric acid reactive substances concentration in the blood, liver, and kidney of rats was also significantly decreased in B. braunii treated samples compared with those of control. Carotenoids (violaxanthin, astaxanthin, lutein, zeaxanthin, chlorophylls a and b, and alpha, beta-carotene) identified in the B. braunii acetone extract may be exhibiting antioxidant activity. Among the carotenoids, lutein represents more than 75% of the total carotenoids. B. braunii extract was shown to be effective for protecting biological systems against various oxidative stresses in vitro. This is the first report on the antioxidant properties of B. braunii.  相似文献   

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