Stability and bioaccessibility of different forms of carotenoids and vitamin A during in vitro digestion

Vitamin A deficiency is a public health issue in developing countries and promoting dietary carotenoids as precursors is a promising strategy. However, carotenoids present in numerous fruits and vegetables are unstable and poorly bioaccessible. This study evaluated these two parameters during in vitro digestion of carotenoids and retinoids from carrot juice, raw and cooked spinach, micronutrient-fortified flour and standards without food matrix. Standards were unstable whereas vitamin A from fortified flour and native food carotenoids were generally better protected by the food matrix (30–100% remaining versus 7–30% for standards). Hydrothermal cooking did not influence spinach carotenoid digestive stability but decreased their contents, phenomenon compensated by a significantly better micellarisation from 15-fold for β-carotene to 72-fold for lutein. Finally, carrot juice provided the greatest amount of bioaccessible provitamin A with 1850 μg/100 g dry matter (DM) versus 790 and 80 μg/100 g DM in cooked and raw spinach, respectively.     

Carotenoid composition from the Brazilian tropical fruit camu–camu (Myrciaria dubia)

Camu–camu (Myrciaria dubia) is a small berry, native to the Amazon, known as a rich source of ascorbic acid. The carotenoid composition of this fruit was determined using high performance liquid chromatography-diode array detection on C₁₈ and C₃₀ columns. Fruits produced in two different regions of São Paulo State, Iguape and Mirandópolis, were analysed. All-trans-lutein was the major carotenoid in camu–camu fruits from both regions, ranging from 45% to 55% of the total carotenoid content (160.5 ± 93.1 μg/100 g for Iguape and 601.9 ± 75.6 μg/100 g for Mirandópolis fruits), followed by β-carotene, violaxanthin and luteoxanthin. The levels of lutein, β-carotene, violaxanthin, luteoxanthin and other minor carotenoids were significantly higher in the camu–camu produced in Mirandópolis region, most probably due to the higher temperature and light exposure found in this region, in comparison to those from Iguape. Maturation was also an important feature affecting batches from the same region.     

Carotenoid composition of Algerian date varieties (Phoenix dactylifera) at different edible maturation stages

The aim of this study was to investigate the carotenoid composition and the provitamin A value of three palm date (Phoenix dactylifera) varieties (Deglet-Nour, Hamraya and Tantebouchte) from Algeria at three different ripening stages (khallal, rutab and tamr). Chromatographic analysis showed that the major carotenoid pigment present in dates is lutein followed by β-carotene, with an evident carotenoid disappearance during ripening from the khallal to the tamr stage. The different date fruits present a total carotenoid content in the range of 61.7–167, 32.6–672, and 37.3–773 μg/100 g fresh weight (FW) in Deglet-nour, Tantebouchte and Hamraya varieties, respectively. The rutab stage of Tantebouchte showed the lowest carotenoid content of 32.6 μg/100 g FW, whereas the khallal stage of Hamraya presented the highest value, 773 μg/100 g FW, followed by Tantebouchte with 672 μg/100 g FW. Provitamin A value (due exclusively to β-carotene) increased from 0.4 to 0.5 RE/100 g in Deglet-Nour fruits, but decreased from 11.7 to 1.6 RE/100 g and from 3.9 to 0.5 RE/100 g in Tantebouchte and Hamraya fruits, respectively, during ripening. The lowest value was found at the tamr stage of the Deglet-Nour variety (0.5 RE/100 g) whereas the highest provitamin A content was found at the khallal stage of the Tantebouchte variety (11.7 RE/100 g).     

Sacha inchi (Plukenetia volubilis): A seed source of polyunsaturated fatty acids,tocopherols, phytosterols,phenolic compounds and antioxidant capacity

Fatty acids (FA), phytosterols, tocopherols, phenolic compounds, total carotenoids and hydrophilic and lipophilic ORAC antioxidant capacities were evaluated in 16 cultivars of Sacha inchi (SI) seeds with the aim to valorise them and offer more information on the functional properties of SI seeds. A high α linolenic (α-Ln) fatty acid content was found in all cultivars (ω3, 12.8–16.0 g/100 g seed), followed by linoleic (L) fatty acid (ω6, 12.4–14.1 g/100 g seed). The ratio ω6/ω3 was within the 0.83–1.09 range. γ- and δ-tocopherols were the most important tocopherols, whereas the most representative phytosterols were β-sitosterol and stigmasterol. Contents of total phenolics, total carotenoids and hydrophilic and lipophilic antioxidant capacities ranged from 64.6 to 80 mg of gallic acid equivalent/100 g seed; from 0.07 to 0.09 mg of β-carotene equivalent/100 g of seed; from 4.3 to 7.3 and, from 1.0 to 2.8 μmol of Trolox equivalent/g of seed, respectively, among the evaluated SI cultivars. Results showed significant differences (p < 0.05) among the evaluated SI cultivars in the contents of ω3, ω6, antioxidant capacities and other evaluated phytochemicals. SI seeds should be considered as an important dietary source of health promoting phytochemicals.     

Carotenoid contents of extruded and non-extruded sweetpotato flours from Papua New Guinea and Australia

Carotenoid contents of extruded and non-extruded flours of Papua New Guinean and Australian sweetpotato cultivars were studied, using spectrophotometry and high performance liquid chromatography (HPLC). The cultivars differed (p < 0.05) in their total carotenoid and β-carotene contents, and the Original Beauregard cultivar had the highest total carotenoid and β-carotene contents among the cultivars. The spectrophotometry (84–1720 μg/g solids) method generally over-estimated the total carotenoid content compared to the more specific HPLC (23–355 μg/g solids) method. Extrusion significantly (p < 0.05) decreased the ΔL^∗ Hunter colour values, while the Δa^∗, Δb^∗, total colour change (ΔE), chroma (CR), and browning indices (BI) increased. With the extruder and screw configuration used, extrusion at 40% moisture and 300 rpm screw speed retained carotenoid maximally at more than 80%. This study reports, for the first time, carotenoids of flours from south Pacific sweetpotato cultivars, and carotenoid retention during extrusion.     

Carotenoid composition and retinol equivalent in plants of nutritional and medicinal importance: Efficacy of β-carotene from Chenopodiumalbum in retinol-deficient rats

This study aimed to (1) quantify carotenoids in leafy vegetables and plants of nutritional and medicinal importance, (2) evaluate retinol equivalent (RE) of provitamin-A carotenoids and (3) determine efficacy of β-carotene from Chenopodium album and to compare with retinol formed on feeding to retinol-deficient rats for 3 weeks. β-Carotene and lutein contents (mg/100 g dry weight) ranged from 1.5 to 120 and 11.7 to 185 (leafy greens) and 0.4 to 34.7 and 11.8 to 679 (medicinal plants) whereas, α-carotene ranged from 0.3 to 35.6 (leafy greens) and 0.1 to 15.7 (medicinal plants). RE values (mg%) ranged from 0.4 to 20 and 0.42 to 5.8 in leafy greens and medicinal plants. Efficacy of β-carotene (2400 μg/kg diet) from C. album in retinol-deficient rats revealed a 93.6% rise in plasma retinol levels from 0.53 to 8.4 μM. The plants analysed are a good source of retinol precursors and biologically active lutein; therefore can be exploited to meet carotenoid requirements.     

An evaluation of carotenoid levels and composition of glabrous canaryseed

Nineteen glabrous canaryseeds comprising brown- and yellow-coloured varieties were investigated to determine carotenoid content and their properties. Total carotenoid content of canaryseeds ranged from 7.57 to 11.69 mg/kg. β-Carotene, lutein, and zeaxanthin were the major carotenoids of glabrous canaryseed. β-Carotene ranged from 5291 to 6273, 4564 to 5352, and 3651 to 4428 μg/kg while lutein ranged from 2667 to 3370, 1532 to 3007, and 2042 to 2299 μg/kg, respectively in canaryseed flour, wholemeal and bran. Zeaxanthin was relatively low (?650 μg/kg). High β-carotene levels distinguished glabrous canaryseeds from other cereal crops as potential ingredients for carotenoid-enriched functional foods.     

Total and individual carotenoids and phenolic acids content in fresh,refrigerated and processed spinach (Spinacia oleracea L.)

The carotenoid and phenolic acid contents in fresh, stored and processed (blanched, frozen and boiled) spinach were comparatively determined by spectrophotometric and HPLC analyses. The major carotenoids identified after HPLC analysis in saponified samples were lutein (37–53 μg/kg), β-carotene (18–31 μg/kg), violaxanthin (9–23 μg/kg) and neoxanthin (10–22 μg/kg). These carotenoids were all affected by storage and/or heating. The content of carotenoids was best preserved after storage for one day at 4 °C.     

Carotenoid composition and vitamin A activity of medicinally important green leafy vegetables

Carotenoid composition of green leafy vegetables (GLVs, n = 30) with medicinal value was analyzed by HPLC; vitamin A activity (as retinol equivalent, RE) of provitamin A carotenoids was calculated. Results show that among GLVs studied, the level of β-carotene (50–130 mg/100 g dry wt) was higher in nine GLVs than other carotenoids while lutein (50–187 mg/100 g dry wt) and zeaxanthin (1–5 mg/100 g dry wt) were higher in 12 GLVs than other xanthophylls. α-Carotene was detected only in nine GLVs, ranging from 1 to 37 mg/100 g dry wt. Interestingly, Chenopodium album, Commelina benghalensis and Solanum nigrum were found to contain higher levels of both lutein and β-carotene in the range of 84–187 and 50–115 mg/100 g dry wt, respectively. The values of retinol equivalents (RE) ranged from 641 to 19101 and were higher (>10,000) in six GLVs of the 30. The results demonstrate that GLVs studied contained higher levels of RE and lutein.     

Carotenoids of yeasts isolated from the Brazilian ecosystem

The carotenoid composition of pigmented yeasts isolated in Brazil was studied. The yeasts were cultured in yeast malt broth at 200 rpm, 25 °C, for 5 days, without illumination. Open column, thin layer and high performance liquid chromatography were used to separate, identify and quantify the carotenoids. The major pigments found in these yeasts were torulene and β-carotene. β-Carotene predominated in Rhodotorula graminis-125, Rhodotorula glutinis and Sporobolomyces roseus, while torulene was the principal carotenoid in Rhodotorula mucilaginosa. The yeast R. glutinis had the highest total carotenoid production (881 μg/l), followed by R. graminis (594 μg/l), Rhodotorula mucilaginosa-137 (590 μg/l), Rhodotorula mucilaginosa-108 (562 μg/l) and Rhodotorula mucilaginosa-135 (545 μg/l). Rhodotorula minuta and S. roseus had the lowest carotenoid contents (168 and 237 μg/l, respectively). In μg/g of dry cells, R. glutinis had a total carotenoid concentration of 132 μg/g.     

Separation and identification of the yellow carotenoids in Potamogeton crispus L.

It was found that ducks fed with Potamogeton crispus L. could lay natural red-yolk eggs with good quality in vast lake areas. P. crispus L. was found to be a new resource of carotenoids based on this fact. Carotenoids from P. crispus L. were extracted using petroleum ether-acetone and saponified using 40% methanolic potassium hydroxide. Four major yellow carotenoid pigments were obtained by a MgO column and thin-layer chromatography. These carotenoids were identified as neoxanthin, violaxanthin, lutein and β-carotene based on visible spectra in different solvents compared with values reported in the literature, functional group tests and mass spectrum by LC-MS. The content of total carotenoids from P. crispus L. was measured to be 231 μg/g (dry weight) by visible absorption spectroscopy.     

Phytochemical and antioxidant characterization of the fruit of black sapote (Diospyros digyna Jacq.)

Consumption of fruits and vegetables has been associated with a healthy state which has been attributed, in part, to their antioxidant capacity. Characterization of the bioactive compounds with antioxidant activity found in fruits cultivated in the tropic is limited. Thus, the objective of the present work was the characterization of phytochemicals and antioxidants of the fruit of black sapote (Diospyros digyna Jacq.). HPLC-DAD-Mass Spectrometry (HPLC-MS) analyses were used to identify and quantify phenolics, carotenoids and tocopherols. Total soluble phenolic content was 247.8 mg GAE/100 g fw (fresh weight). Important phenolics identified were sinapic acid, myricetin, ferulic acid, and catechin. Total carotenoid content was 399.4 ??g of ??-carotene/100 g fw, and ??-carotene and lutein were the main carotenoids identified. ??-Tocopherol concentration was 672.0 ??g/100 g dry weight. Antioxidant capacity as measured by the DPPH and FRAP assays was higher in the hydrophilic than in the lipophilic extract, and it is thought to be due mainly to the phenolic content of this fruit. Results suggest that the fruit of black sapote has an antioxidant capacity comparable to other important fruits, and its inclusion in the diet is therefore recommended.     

Changes on phenolic and carotenoid composition of high intensity pulsed electric field and thermally treated fruit juice–soymilk beverages during refrigerated storage

The effects of high intensity pulsed electric fields (HIPEF) (35 kV/cm with 4 μs bipolar pulses at 200 Hz for 800 or 1400 μs) or thermal (90 °C, 60 s) treatments over phenolic and carotenoid compounds of a fruit juice–soymilk (FJ–SM) beverage stored at 4 °C were evaluated and compared, having the untreated beverage as a reference. Coumaric acid, narirutin and hesperidin were the most abundant phenolic compounds in the FJ–SM beverage, while the main carotenoids were lutein, zeaxanthin and β-carotene. Immediately after HIPEF or heat processing, hesperidin content of the beverage showed a huge rise, resulting in a significant increase on the total phenolic concentration. Regarding carotenoid concentration, HIPEF or thermal treatment lead to a significant decrease; lutein, zeaxanthin and β-cryptoxanthin being the most affected compounds. In contrast, the content of some individual phenolics and carotenoids increased with time, while others tended to decrease or remained with no significant changes with regards to their initial values. Total phenolic concentration seemed to be highly stable during storage; while, total carotenoid content gradually diminished, irrespectively of the treatment applied. Overall, the changes observed in HIPEF treated FJ–SM beverage were less than those in the heat processed one. Hence, HIPEF is a feasible technology to obtain FJ–SM beverages with extended shelf-life and a similar profile of antioxidant compounds to freshly made beverages.     

The effect of domestic processing on the content and bioaccessibility of carotenoids from chili peppers (Capsicum species)

The content and bioaccessibility of carotenoids from different chili peppers were analysed and the effects of typical domestic processing were investigated. Peppers were analysed before and after cooking by conventional boiling (10 min in 100 °C water) and also following a freezing period of four months in a domestic freezer (−20 °C). The content and bioaccessibility of the eight carotenoids quantified varied, depending on cultivar, species, colour and processing. Provitamin A carotenoids (β-carotene and β-cryptoxanthin) and capsanthin were present at highest concentrations in the samples before and after processing. In general, yellow and orange peppers were the best sources of lutein, zeaxanthin and neoxanthin. Xanthophyll carotenoids were more efficiently transferred to the micelles and, therefore, were also more bioavailable. Processing decreased the carotenoid content in certain samples; however, the micellar content was generally not lower for processed peppers; therefore the bioaccessibility of carotenoids from processed peppers is enhanced relative to unprocessed peppers.     

Profiles of carotenoids during post-climacteric ripening of some important cultivars of banana and development of a dry product from a high carotenoid yielding variety

Since vitamin A deficiency is prevalent in many developing countries, we sought to focus research on local, affordable and well-accepted sources of provitamin A carotenoids. As dessert bananas are consumed fresh round the year and processed as products, this study investigated whether post-climacteric biochemical changes are linked to carotenoid degradation in four Indian varieties, one commercial (Cavendish, AAA), one Red banana (genome AAA) and two locally-important ones (genome AAB). Despite large differences in their ripening characteristics, textural loss was lesser in AABs than AAAs. High levels of carotenoids (21.0 μg/g FW), β-carotene (9.14 μg/g FW) and α-carotene (9.32 μg/g FW) were found in Red banana accounting for retinol activity equivalent of 114 μg/100 g FW. The carotenoid levels were lower in two local varieties and lowest in Cavendish, with no post-climacteric loss. Dry grits, prepared using Red banana pulp, milk powder and sugar, retained about 70% carotenoids and appeared useful in confectionaries.     

Characterisation,extraction efficiency,stability and antioxidant activity of phytonutrients in Angelica keiskei

Phytonutrients in Angelica keiskei, a dark green leafy vegetable, were characterised and their extraction efficiency by different compositions of water/ethanol as well as stability at different temperatures was determined. A range in the content of lutein (205–265 mg/kg dry wt), trans-β-carotene (103–130 mg/kg dry wt), and total phenols (8.6–9.7 g/kg) was observed amongst Angelica keiskei grown in three different conditions. LC-ESI-MS/MS analysis identified chlorogenic acid, chalcones and the glucosides of luteolin and quercetin as the major phenolic compounds in Angelica keiskei. Only 46% of lutein was extracted by 70% of ethanol and no carotenoid was detected in 40% ethanol and 100% water extracts of Angelica keiskei. Major phytonutrients in Angelica keiskei were stable at −80 °C up to 12 months whilst β-carotene was significantly degraded at room temperature and 4 °C within 2 months and lutein at room temperature within 12 months.     

Phytochemical and antioxidant characterization of mamey (Pouteria sapota Jacq. H.E. Moore & Stearn) fruit

Phytochemical compounds in fruits and vegetables have gained great importance in the last few years because of the increasing evidence suggesting their antioxidant and prevention of chronic diseases. Carotenoids, phenolics, flavonoids, and vitamins E and C, are among these phytochemicals. Several fruits have been characterized so far for their antioxidant and health properties but there is still limited information on fruits from the tropic. Therefore, the objective of this study was the characterization of mamey fruit (Pouteria sapota Jacq. H. E. Moore & Stearn) with regard to their antioxidant capacity and phytochemical profile. Phenolics, carotenoids and ??-tocopherol were quantified and identified by HPLC-DAD-Mass Spectrometry (LC-MS), and DPPH and FRAP assays were used to evaluate antioxidant capacity. Hydrophilic extracts of mamey fruit showed higher antioxidant capacity than the lipophilic portion. Total soluble phenols content was 28.5 mg GAE/100 g fw, being p-hydroxybenzoic acid as the main phenolic that was identified. Total carotenoid content was 1127.9 ??g ??-carotene/100 g fw with ??-carotene being the main contributor, in addition to lutein, and violoxanthin. Concentration of ??-tocopherol was 360.0 ??g/100 g fw. Results of this study suggest that mamey fruit is a good source of carotenoids and its inclusion in the diet is recommended.     

Effects of genetic variability,parts and seasons on the sterol content and composition in bamboo shoots

Bamboo shoots are regarded as potential sources of sterols. The effects of genetic variability, parts and harvest seasons on the sterol content and composition in the bamboo shoots have been determined using a novel ultra-performance liquid chromatographic atmospheric pressure chemical ionisation mass spectrometer method. The results showed that the representative sterols in bamboo shoots were β-sitosterol, campesterol, stigmasterol, ergosterol, cholesterol and stigmastanol; exception stigmastanol, the significant differences were observed in the sterol content of different species (112.4–279.6 mg/100 g dry wt), different harvest seasons (195.3–279.6 mg/100 g dry wt) and different parts (253.6–321.8 mg/100 g dry wt); the sterol composition was similar in different species and different harvest seasons, however, it was significantly different between shoot bodies and shoot shell. The genetic variability, parts and harvest seasons could significantly affect the sterol composition in the bamboo shoots. The spring shoot shell of Phyllostachys pubescens contained the highest sterol content (321.8 mg/100 g dry wt).     

Vitamin C and carotenoids in organic and conventional fruits grown in Brazil

This study compared the concentration of vitamin C (ascorbic acid, AA, and dehydroascorbic acid, DHA) and carotenoids (lycopene and β-carotene) between three fruits produced by organic and conventional farming. Vitamin C and carotenoids were analysed by high-performance liquid chromatography. The Student t-test (α = 5%) was applied to determine differences between the organic and conventional production systems. AA content was significantly higher in organic acerola (4023.39 mg/100 g) compared to its conventional production (2294.53 mg/100 g). Conversely, AA content was significantly higher in conventional strawberries (42.45 mg/100 g) than the organic ones (30.74 mg/100 g). The conventional production also showed significantly higher contents of DHA (persimmon: 7.50 mg/100 g vs. 0.96 mg/100 g) and β-carotene (acerola: 6130.24 μg/100 g vs. 2486.38 μg/100 g) than the organic fruits. Lycopene was only detected in persimmons, but no significant difference was observed between farming systems. There was no evidence of the nutritional superiority of the organically grown fruits.     

Identification and quantification of carotenoids by HPLC-DAD during the process of peach palm (Bactris gasipaes H.B.K.) flour

The identification and quantification of carotenoids has been carried out on tropical and non tropical fruits because of two important carotenoid's properties: as antioxidant compounds having a prevention role in some diseases, and as a source of provitamin A needed for a good human nutrition. This study aimed to identify carotenoids present during different steps for producing flour from Costa Rican peach-palm fruit (Bactris gasipaes H.B.K). Nine carotenoids were tentatively identified and quantified by HPLC-DAD in raw pulp, and 14 were detected in cooked pulp, the additional five being products of isomerization and hydroxylation of carotenoids in the raw pulp. The flour contained 13 carotenoids, one less (all-trans-??-criptoxanthin) than in cooked pulp, with the main one being all-trans ??-carotene. This carotenoid was also present in raw pulp at a concentration of 96.0 ± 1.7 ??g equiv. of ??-carotene g⁻¹ dw. The concentration decreased significantly (P < 0.05) during cooking and drying to reach a final concentration of 33.3 ± 1.0 ??g equiv. ??-carotene g⁻¹ dw in the flour. Flour production reduced (P < 0.05) the total carotenoid content from 373.4 to 237.7 ??g of ??-carotene g⁻¹ dw, with a final retention rate of 63.7% by the end of the process. Moreover, 9 of the 14 carotenoids account for high levels of provitamin A, which, even so, had decreased from 2723 retinol equivalents (RE) 100 g⁻¹ in raw pulp to 1614 RE 100 g⁻¹ in cooked pulp and 1289 RE 100 g⁻¹ in flour. Provitamin A level is still high when compared to other common provitamin A sources. Our study shows that while there is a change in the levels and profile of carotenoids during the peach-palm flour process, and a reduction of provitamin A value, peach-palm fruit is a great source of bioactive compounds.