Functional Properties of Carotenoids in Human Health

Extraction, Identification and Photo-Physical Characterization of Persimmon (Diospyros kaki L.) Carotenoids

Carotenoid pigments were extracted and purified from persimmon fruits using accelerated solvent extraction (ASE). Eleven pigments were isolated and five of them were clearly identified as all-trans-violaxanthine, all-trans-lutein, all-trans-zeaxanthin all-trans-cryptoxanthin and all-trans-β-carotene. Absorption and fluorescence spectra were recorded. To evaluate the potential of ¹O₂ quenching of the purified carotenoids, we used a monocarboxylic porphyrin (P1COOH) as the photosensitizer to produce ¹O₂. The rate constants of singlet oxygen quenching (Kq) were determined by monitoring the near-infrared (1270 nm) luminescence of ¹O₂ produced by photosensitizer excitation. The lifetime of singlet oxygen was measured in the presence of increasing concentrations of carotenoids in hexane. Recorded Kq values show that all-trans-β-cryptoxanthin, all-trans-β-carotene, all-trans-lycopene and all-trans-zeaxanthin quench singlet oxygen in hexane efficiently (associated Kq values of 1.6 × 10⁸, 1.3 × 10⁸, 1.1 × 10⁸ and 1.1 × 10⁸ M^-1·s^-1, respectively). The efficiency of singlet oxygen quenching of β-cryptoxanthin can thus change the consideration that β-carotene and lycopene are the most efficient singlet oxygen quenchers acting as catalysts for deactivation of the harmful ¹O₂.

Glucosinolates, Carotenoids, and Vitamins E and K Variation from Selected Kale and Collard Cultivars

Glucosinolates, carotenoids, and fat-soluble vitamins E and K contents were analyzed from various kale and collard cultivars at mature stage. We found a significant difference in these phytonutrients among cultivars. Among kale cultivars, “Beira” and “Olympic Red” were the highest in the total glucosinolate and “Toscano” kale was the highest in total carotenoid content. “Scarlet” kale was highest in tocopherols. For collard, total glucosinolate was the highest in “Top Bunch” while carotenoids were the highest in “Green Glaze.” An accession PI261597 was the highest in phylloquinone. In addition to the total content of each phytonutrient class, their composition differed among cultivars, indicating that each cultivar may have differential regulatory mechanisms for biosynthesis of these phytonutrients. Our result indicates that cultivar selection may play an important role in consumption of kale and collard with greater nutritional benefit. Therefore, the result of this study will provide a more thorough profile of essential and nonessential phytonutrients of kale and collard cultivars for consumers’ choice and for future research on nutritional value of these crops.

Application of ultra-high performance supercritical fluid chromatography for the determination of carotenoids in dietary supplements

A quick and simple ultra-high performance supercritical fluid chromatography-photodiode array detector method was developed and validated for the simultaneous determination of 9 carotenoids in dietary supplements. The influences of stationary phase, co-solvent, pressure, temperature and flow rate on the separation of carotenoids were evaluated. The separation of the carotenoids was carried out using an Acquity UPC(2) HSS C18 SB column (150mm×3.0mm, 1.8μm) by gradient elution with carbon dioxide and a 1:2 (v:v) methanol/ethanol mixture. The column temperature was set to 35°C and the backpressure was 15.2MPa. Under these conditions, 9 carotenoids and the internal standard, β-apo-8'-carotenal, were successfully separated within 10min. The correlation coefficients (R(2)) of the calibration curves were all above 0.997, the limits of detection for the 9 carotenoids were in the range of 0.33-1.08μg/mL, and the limits of quantification were in the range of 1.09-3.58μg/mL. The mean recoveries were from 93.4% to 109.5% at different spiking levels, and the relative standard deviations were between 0.8% and 6.0%. This method was successfully applied to the determination of 9 carotenoids in commercial dietary supplements.

Dietary intake of carotenoids and risk of type 2 diabetes

BACKGROUND AND AIMS

Carotenoids may reduce diabetes risk, due to their antioxidant properties. However, the association between dietary carotenoids intake and type 2 diabetes risk is still unclear. Therefore, the objective of this study was to examine whether higher dietary carotenoid intakes associate with reduced type 2 diabetes risk.

METHODS AND RESULTS

Data from 37,846 participants of the European Prospective Investigation into Cancer and Nutrition- Netherlands study were analyzed. Dietary intakes of β-carotene, α-carotene, β-cryptoxanthin, lycopene, lutein & zeaxanthin and the sum of these carotenoids were assessed using a validated food frequency questionnaire. Incident type 2 diabetes was mainly self-reported, and verified against general practitioner information. Mean ±SD total carotenoid intake was 10 ± 4 mg/day. During a mean ±SD follow-up of 10 ± 2 years, 915 incident cases of type 2 diabetes were ascertained. After adjustment for age, sex, diabetes risk factors, dietary intake, waist circumference and BMI, higher β-carotene intakes associated inversely with diabetes risk [Hazard Ratio quartile 4 versus quartile 1 (HR(Q4)): 0.78 (95%CI:0.64,0.95), P-linear trend 0.01]. For α-carotene, a borderline significant reduced risk was observed, with a HR(Q4) of 0.85 (95%CI:0.70,1.03), and P-linear trend 0.05. β-cryptoxanthin, lycopene, lutein & zeaxanthin, and the sum of all carotenoids did not associate with diabetes risk.

CONCLUSIONS

This study shows that diets high in β-carotene and α-carotene are associated with reduced type 2 diabetes in generally healthy men and women.

Impact of soil management practices on yield, fruit quality, and antioxidant contents of pepper at four stages of fruit development

Peppers, a significant component of the human diet in many regions of the world, provide vitamins A (β-carotene) and C, and are also a source of many other antioxidants such as capsaicin, dihydrocapsaicin, and phenols. Enhancing the concentration of antioxidants in plants grown in soil amended with recycled waste has not been completely investigated. Changes in pepper antioxidant content in relation to soil amendments and fruit development were investigated. The main objectives of this investigation were to: (i) quantify concentrations of capsaicin, dihydrocapsaicin, β-carotene, ascorbic acid, phenols, and soluble sugars in the fruits of Capsicum annuum L. (cv. Xcatic) grown under four soil management practices: yard waste (YW), sewage sludge (SS), chicken manure (CM), and no-much (NM) bare soil and (ii) monitor antioxidant concentrations in fruits of plants grown under these practices and during fruit ripening from green into red mature fruits. Total marketable pepper yield was increased by 34% and 15% in SS and CM treatments, respectively, compared to NM bare soil; whereas, the number of culls (fruits that fail to meet the requirements of foregoing grades) was lower in YW compared to SS and CM treatments. Regardless of fruit color, pepper fruits from YW amended soil contained the greatest concentrations of capsaicin and dihydrocapsaicin. When different colored pepper fruits (green, yellow, orange, and red) were analyzed, orange and red contained the greatest β-carotene and sugar contents; whereas, green fruits contained the greatest concentrations of total phenols and ascorbic acid.

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.

Response surface optimization of ultrasonic-assisted extraction of carotenoids from oil palm (Elaeis guineensis Jacq.) fronds

Oil palm (Elaeis guineensis Jacq.) fronds (OPF) are the most abundant oil palm solid wastes that are generated during oil palm agriculture and harvest. Palm oil and some other palm wastes have been reported to contain high concentrations of carotenoids with vital bioactive properties. However, the extraction and quantification of carotenoids from OPF have not been reported. In this study, ultrasonic-assisted extraction, HPLC-FLD for quantification, and response surface methodology (RSM) for optimization of β-carotene, lutein, and zeaxanthin from OPF extracts were investigated. The effects of extraction temperature (X₁: 30-70°C), extraction time (X₂: 10-50 min), and solvent-sample ratio (X₃: 10-50 mL/g) on the recovery of β-carotene (Y₁), lutein (Y₂), and zeaxanthin (Y₃) were investigated using three-level Box-Behnken design (BBD) experiment. At a desirability of 1, the optimum extraction conditions for β-carotene (30.14°C, 37.11 min, and 23.18 mL/g), lutein (30.00°C, 39.09 min, and 19.24 mL/g), and zeaxanthin (30.09°C, 36.76 min, and 22.38 mL/g) yielded carotenoid concentrations of 17.95 μg/g dry weight (DW), 261.99 μg/g DW, and 29.99 μg/g DW, respectively.

Ultrasound assisted extraction of β-carotene from Spirulina platensis

This paper illustrates the Ultrasound Assisted Extraction (UAE) of β-carotene from Spirulina platensis. Various parameters such as extraction time, solvent type, biomass to solvent ratio, temperature, electrical acoustic intensity, length of the probe tip dipped into the solvent, duty cycle and pre treatment effect were explored for the extraction of β-carotene. From economic point of view, the optimal conditions for the extraction of β-carotene from Spirulina were 1.5 g Spirulina (2 min pre soaked in methanol) in 50 ml n-heptane at 30 ° C temperature, 167 W/cm(2) electrical acoustic intensity and 61.5% duty cycle for 8 min with probe tip length of 0.5 cm dipped into the extracting solvent from the surface. The maximum extraction achieved under the above mentioned optimum parameters was 47.10%. The pre-treatment time showed a promising effect on the yield as pre-treating the biomass with methanol for 2 min before ultrasonication showed 12 times increase in extraction yield of β-carotene.

Health biomarkers in a rat model after intake of organically grown carrots

BACKGROUND

Organic food is perceived as being of better quality and healthier than conventional foods although the scientific research on organic foodstuffs is highly contradictory. The aim of the present study was to investigate if intake of carrots from four different cultivation systems grown in two consecutive years would influence various biomarkers of health in a rat model. All rats were fed a diet with 40% carrot content. The carrots were grown under conventional (C), 'minimalistic' organic (O1), organic (O2), or 'very' organic cultivation systems (O3). A control group (CO) being fed standard rat chow was included.

RESULTS

The plasma α-tocopherol concentration was higher in the O2 carrot-based diet group than in the C carrot based-diet group in one year, while all other health biomarkers or nutrient content differences were observed between the CO diet and the carrot-based diets.

CONCLUSION

This well-controlled field study demonstrated no clear influence of cultivation methods or harvest year on the nutritional quality of carrots or effect of cultivation methods on health-related biomarkers in a sensitive rat model. However, the experimental set-up and selected biomarkers could be used as a framework for further studies of health in relation to organic foodstuff.

Impact of organic and conventional carrots on intestinal and peripheral immunity

BACKGROUND

Studies on health effects of organic (ORG) products are still limited and often contradictory. We have investigated the impact of ORG and conventional (CV) carrots from two consecutive harvest years on mouse peripheral and intestinal immunity.

RESULTS

Danish carrots (Bolero variety) were grown in three ORG (O1, O2 and O3) and one CV cropping system (D-CV). Italian carrots (Maestro and Excelso varieties) were grown in one ORG and one CV field for each variety. Immune phenotypes of blood, spleen and intestinal lymphocytes, and cytokine serum levels were analyzed in mice fed the different carrots for 30 days. Principal component analysis (PCA) was performed in mice fed the Danish carrots. The consumption of the 'more organic' O2 and O3 carrots induced some changes in lymphocyte populations, including an increase in regulatory T cells. In Italian carrots more differences between ORG and CV were observed in the first as compared to the second year. No relevant differences were observed in cytokine secretion. PCA showed a clear separation among mice fed the O1, O2, O3 and D-CV carrots.

CONCLUSIONS

Although a great variability was observed between the two years, an immune stimulation was found after the ORG carrot consumption.

Differences in carotenoid accumulation among three feeder-cricket species: implications for carotenoid delivery to captive insectivores

There are a limited number of feeder-invertebrates available to feed captive insectivores, and many are deficient in certain nutrients. Gut-loading is used to increase the diversity of nutrients present in the captive insectivore diet; however, little is known about delivery of carotenoids via gut-loading. Carotenoids may influence health and reproduction due to their roles in immune and antioxidant systems. We assessed interspecific variation in carotenoid accumulation and retention in three feeder-cricket species (Gryllus bimaculatus, Gryllodes sigillatus and Acheta domesticus) fed one of three diets (wheat-bran, fish-food based formulated diet, and fresh fruit and vegetables). Out of the three species of feeder-cricket in the fish-food-based dietary treatment group, G. bimaculatus had the greatest total carotenoid concentration. All cricket species fed the wheat-bran diet had very low carotenoid concentrations. Species on the fish-food-based diet had intermediate carotenoid concentrations, and those on the fruit and vegetable diet had the highest concentrations. Carotenoid retention was poor across all species. Overall, this study shows that, by providing captive insectivores with G. bimaculatus crickets recently fed a carotenoid-rich diet, the quantity of carotenoids in the diet can be increased.

Influence of different drying methods on carotenoids and capsaicinoids of paprika (Cv., Jalapeno)

Influence of Refractance Window™ Drying (RWD), a novel contact drying method, on carotenoids, capsaicinoids, Retinol Activity Equivalent (RAE) and Scoville Heat Unit (SHU) of paprika (Cv., Jalapeno) was investigated in comparison with freeze drying (FD), oven drying (OD), and natural convective drying (NCD) methods. Eight carotenoids (capsanthin, capsorubin, capsolutein, β-carotene, β-cryptoxanthin, mutatoxanthin, violaxanthin and zeaxanthin) and five capsaicinoid analogues (capsaicin, dihydrocapsaicin, homodihydrocapsaicin, isodihydrocapsaicin, nordihydrocapsaicin) were identified in paprika. All these components were significantly (P<0.05) decreased by the RWD, FD and OD methods. However, due to ongoing synthesis, the NCD method resulted in higher carotenoids, except violaxanthin and mutatoxanthin, and capsaicinoids content than those of the others, even puree. Mutatoxanthin, naturally occurring pigment in red pepper, could only be detected in FD paprika. The highest RAE and SHU values, which were derived from the data of carotenoids and capsaicinoids, respectively, were also determined in NCD paprika.

Effects of organic and conventional growth systems on the content of carotenoids in carrot roots, and on intake and plasma status of carotenoids in humans

BACKGROUND

The demand for organic food products has increased during the last decades due to their probable health effects, among others. A higher content of secondary metabolites such as carotenoids in organic food products has been claimed, though not documented, to contribute to increased health effects of organic foods. The aim was to study the impact of organic and conventional agricultural systems on the content of carotenoids in carrots and human diets. In addition, a human cross-over study was performed, measuring the plasma status of carotenoids in humans consuming diets made from crops from these agricultural systems.

RESULTS

The content of carotenoids in carrot roots and human diets was not significantly affected by the agricultural production system or year, despite differences in fertilisation strategy and levels. The plasma status of carotenoids increased significantly after consumption of the organic and conventional diets, but no systematic differences between the agricultural production systems were observed.

CONCLUSION

The expected higher content of presumed health-promoting carotenoids in organic food products was not documented in this study.

Effects of different factors of ultrasound treatment on the extraction yield of the all-trans-β-carotene from citrus peels

The effects of different factors, including the material's particle size, the extraction solvent, solid/solvent ratio, temperature, extraction time, the electrical acoustic intensity, liquid height and duty cycle of ultrasound exposure on the extraction yield of all-trans-β-carotene from citrus peels by ultrasound-assisted extraction (UAE) were investigated. The extraction yield was significantly affected by particle size. Dichloromethane caused the degradation of all-trans-β-carotene extracted during UAE. Ethanol showed a pronounced higher extraction yield during UAE in comparison with classical extraction (CE). The extraction yield of UAE had a peak value at 25°C. In comparison with classical extraction, the extraction yield of UAE did not easily arrive at equilibrium. The extraction yield increased first, then decreased, then slightly increased with an increase in electrical acoustic intensity. The extraction yield of UAE decreased with increased liquid height. The extraction yield increased with increased duty cycle until equilibrium was achieved.

Stability of all-trans-beta-carotene under ultrasound treatment in a model system: effects of different factors, kinetics and newly formed compounds

The effects of factors and kinetics of all-trans-beta-carotene degradation under ultrasound treatment in a model system were investigated. The compounds of degradation were also tentatively identified by HPLC-DAD, Raman and FT-IR spectroscopy. The type of solvents and temperature were important factors in determining the degradation reaction. Liquid height, ultrasonic intensity and duty cycle of ultrasound exposure only affected the rate of degradation but did not change the nature of degradation. Degradation rate of beta-carotene in dichloromethane was the highest. Degradation rate of beta-carotene decreased with increasing of temperature. Degradation kinetics of all-trans-beta-carotene under ultrasound fitted first-order reaction at -5 to 15 degrees C, and fitted second-order reaction at 25 degrees C. Degradation products included isomers: 15-cis-beta-carotene, di-cis-beta-carotene and other compounds with function group of C-O.

Use of response surface methodology in a fed-batch process for optimization of tricarboxylic acid cycle intermediates to achieve high levels of canthaxanthin from Dietzia natronolimnaea HS-1

In this work, we applied statistical experimental design to a fed-batch process for optimization of tricarboxylic acid cycle (TCA) intermediates in order to achieve high-level production of canthaxanthin from Dietzia natronolimnaea HS-1 cultured in beet molasses. A fractional factorial design (screening test) was first conducted on five TCA cycle intermediates. Out of the five TCA cycle intermediates investigated via screening tests, alfaketoglutarate, oxaloacetate and succinate were selected based on their statistically significant (P<0.05) and positive effects on canthaxanthin production. These significant factors were optimized by means of response surface methodology (RSM) in order to achieve high-level production of canthaxanthin. The experimental results of the RSM were fitted with a second-order polynomial equation by means of a multiple regression technique to identify the relationship between canthaxanthin production and the three TCA cycle intermediates. By means of this statistical design under a fed-batch process, the optimum conditions required to achieve the highest level of canthaxanthin (13172 + or - 25 microg l(-1)) were determined as follows: alfaketoglutarate, 9.69 mM; oxaloacetate, 8.68 mM; succinate, 8.51 mM.

Antioxidants in Capsicum chinense: variation among countries of origin

The main objective of this investigation was to evaluate fruits of C. chinense accessions for their concentration of beta -carotene, ascorbic acid, and phenols for use as parents in breeding for these phytochemicals. Mature fruits of 63 accessions of C. chinense originally acquired from Belize, Brazil, Colombia, Ecuador, Mexico, Peru, Puerto Rico, and the United States were analyzed for their chemical composition. Fruits of C. chinense accessions PI-152452 (Brazil) and PI-360726 (Ecuador) contained the greatest concentrations of ascorbic acid (1.2 and 1.1 mg g(-1) fresh fruit, respectively), while PI-438648 (Mexico) contained the greatest concentration of total phenols content (349 micro g g(-1) fresh fruit) among the other 63 accessions tested. Accession PI-355817 from Ecuador contained the greatest concentrations of beta -carotene (8 mg g(-1)fresh fruit). These accessions were identified as potential candidates for mass production of antioxidants with health-promoting properties.

Carotenoids in raw and parboiled brown and milled rice

Color measurements on flour of five raw rice cultivars with different degrees of milling (DOM) showed that red and brown pigments are concentrated in the outer rice layers, i.e. bran and outer endosperm (DOM < 15%). Extinction measurements (lambda 450 nm) of rice extracts showed that yellow pigments are virtually absent in the middle and core endosperm (DOM > 15%). The relation between the extinction values and the yellow color parameter (b*) showed that both are representative for the yellow pigment content of flour from rice with DOM lower than 9%. Determinations of the carotenoid levels in raw brown rice samples indicated that carotenoid levels in raw brown rice are lower than in common nonrice cereals. The major brown rice carotenoids are beta-carotene and lutein (both ca. 100 ng/g), while zeaxanthin levels are lower (ca. 30 ng/g). Regression analyses indicated that yellowness, extinction values, and quantitative carotenoid data are related. b*-Values and contents of total carotenoids (r = 0.70), beta-carotene (r = 0.84), lutein (r = 0.78), and zeaxanthin (r = 0.83) were linearly related. However, extinction values (lambda 450 nm) and contents of total carotenoids (r = 0.92), beta-carotene (r = 0.91), lutein (r = 0.89), and zeaxanthin (r = 0.84) showed the best correlations. The three-step hydrothermal treatment parboiling reduces carotenoid contents of brown rice to trace levels. Consequently, pigments do not contribute to the final color of milled parboiled rice.