Analysis of carotenoids in ripe jackfruit (Artocarpus heterophyllus) kernel and study of their bioconversion in rats

Vitamin A deficiency is of public health importance in Sri Lanka. Carotenoids are a significant source of provitamin A. The objective of this study was to analyse the carotenoid composition of jackfruit (Artocarpus heterophyllus sinhala: Waraka) kernel using MPLC and visible spectrophotometry and to determine the bioavailability and bioconversion of carotenoids present in jackfruit kernel by monitoring (i) the growth and (ii) levels of retinol and carotenoids in the liver and serum of Wistar rats provided with jackfruit incorporated into a standard daily diet. Carotenoid pigments were extracted using petroleum ether/methanol and saponified using 10% methanolic potassium hydroxide. Six carotenoids were detected in jackfruit kernel. The carotenes β‐carotene, α‐carotene, β‐zeacarotene, α‐zeacarotene and β‐carotene‐5,6‐epoxide and a dicarboxylic carotenoid, crocetin, were identified, corresponding theoretically to 141.6 retinol equivalents (RE) per 100 g. Our study indicated that jackfruit is a good source of provitamin A carotenoids, though not as good as papaya. Serum retinol concentrations in rats supplemented with jackfruit carotenoids were significantly higher (p = 0.008) compared with the control group. The same was true for liver retinol (p = 0.006). Quantification was carried out by RP‐HPLC. These results show that the biological conversion of provitamin A in jackfruit kernel appears satisfactory. Thus increased consumption of ripe jackfruit could be advocated as part of a strategy to prevent and control vitamin A deficiency in Sri Lanka. Copyright © 2004 Society of Chemical Industry     

Bioequivalence of β‐carotene and retinol

For many years it was accepted that 6 mg of β‐carotene were required to produce 1 mg of vitamin A in the form of retinol. The equivalence was based on the assumptions that two‐thirds of dietary β‐carotene are not absorbed, while in the metabolism of the remaining third 1 mol of β‐carotene is converted to 1 mol retinol. Recently, the bioequivalence was raised to 12 mg β‐carotene and 1 mg retinol. The objective of this review was to re‐examine the data that were used to support the new equivalence ratio, especially since some of these data were obtained in developing countries where infestation with gut parasites and exposure to other infections is common, yet the influence of inflammation on plasma carotenoid and retinol concentrations is frequently ignored. Bioequivalence studies examined in this review include those done in developing and developed countries, depletion and repletion studies, feeding with vegetable sources of β‐carotene or pure supplements, influence of helminths, carotenoid interactions and matrix effects and studies using stable isotopes (SI). SI studies show the bioefficacy of β‐carotene conversion to retinol is generally poor even for pure β‐carotene unless the dose is small and fed regularly until equilibration is reached. Retinol formation appears to be inversely influenced by previous vitamin A intake, the amount of material given and current vitamin A status. In spite of technical complexities, more SI studies where liver reserves of vitamin A are determined pre and post intervention are needed to evaluate β‐carotene bioefficacy of different vegetable sources. Copyright © 2006 Society of Chemical Industry     

Carotenoids in pungent and non‐pungent peppers at various developmental stages grown in the field and glasshouse

Carotenoids in edible portions of plants can provide health benefits to humans. How growing conditions affect levels of carotenoids in pepper fruits as they mature is not well known. Five cvs of bell pepper (Bell Captain, Melody, North Star, Ranger, Red Beauty) and five cvs of pungent‐type peppers (Anaheim, Ancho, Cayenne, Pimento, Red Cherry) were grown in a glasshouse and in the field. Fruits were harvested at the green, turning (50% green) and mature red stages and analysed for levels of the carotenoids β‐cryptoxanthin, α‐carotene, β‐carotene, capsanthin, lutein and zeaxanthin and totals of these carotenoids. Levels of provitamin A: retinol equivalents (RE) were derived from levels of β‐cryptoxanthin, α‐carotene and β‐carotene. Levels of most carotenoids and RE were significantly higher in glasshouse‐grown plants, and most were higher in fruits at the red stage. Fruits of Ancho type had the most β‐cryptoxanthin, α‐carotene, β‐carotene, total carotenoids and RE, while fruits of Red Cherry type had the most capsanthin and zeaxanthin, and fruits of Bell Captain had the most lutein. Interactions of the main effects variables, ie location of production (field vs glasshouse), stage of development and cultivar, indicated differences in patterns of carotenoid levels and RE. The data indicated that growing conditions influenced carotenoid levels. The more consistent and protected conditions in the glasshouse may have caused carotenoid levels to be increased, especially at the red stage. Published in 2002 for SCI by John Wiley & Sons, Ltd     

Carotenoids in yellow‐ and red‐fleshed papaya (Carica papaya L)

Vitamin A deficiency is a disorder of public health importance in Sri Lanka. A recent national survey revealed that 36% of preschool children in Sri Lanka have vitamin A deficiency (serum retinol <0.2 µg ml^?1). In view of its well‐established association with child morbidity and mortality, this is a reason for concern. One of the main fruits which has been recommended for prevention of vitamin A deficiency in Sri Lanka is papaya (Carica papaya L). In this study the carotenoid profiles of yellow‐ and red‐fleshed papaya were analysed by medium‐pressure liquid chromatography (MPLC) and UV‐vis spectrophotometry. A section of yellow‐fleshed papaya showed small carotenoid globules dispersed all over the cell, whereas in red‐fleshed papaya the carotenoids were accumulated in one large globule. The major carotenoids of yellow‐fleshed papaya were the provitamin A carotenoids β‐carotene (1.4 ± 0.4 µg g^?1 dry weight (DW)) and β‐cryptoxanthin (15.4 ± 3.3 µg g^?1 DW) and the non‐provitamin A carotenoid ζ‐carotene (15.1 ± 3.4 µg g^?1 DW), corresponding theoretically to 1516 ± 342 µg kg^?1 DW mean retinol equivalent (RE). Red‐fleshed papaya contained the provitamin A carotenoids β‐carotene (7.0 ± 0.7 µg g^?1 DW), β‐cryptoxanthin (16.9 ± 2.9 µg g^?1 DW) and β‐carotene‐5,6‐epoxide (2.9 ± 0.6 µg g^?1 DW), and the non‐provitamin A carotenoids lycopene (11.5 ± 1.8 µg g^?1 DW) and ζ‐carotene (9.9 ± 1.1 µg g^?1 DW), corresponding theoretically to 2815 ± 305 µg kg^?1 DW mean RE. Thus the carotenoid profile and organisation of carotenoids in the cell differ in the two varieties of papaya. This study demonstrates that carotenoids can be successfully separated, identified and quantified using the novel technique of MPLC. Copyright © 2003 Society of Chemical Industry     

Effect of processing on the retention of carotenoids in yellow‐fleshed cassava (Manihot esculenta Crantz) roots

The retention of carotenoids was studied in roots from yellow‐fleshed, high carotene cassava clones in four different processing methods. The results indicated that the extent of retention varied with the method of processing. The highest retention was observed in oven drying (total carotenoids 54.70–84.01% and β‐carotene 63.90–94.53%) followed by boiling (total carotenoids 47.87–83.79% and β‐carotene 51.31–81.04%) and frying (total carotenoids 48.76–79.77% and β‐carotene 44.11–83.87%). The lowest retention of total carotenoids (32.86–56.40%) and β‐carotene (21.47–56.68%) was recorded in the sun drying method. The variation in the total carotenoids and β‐carotene content depends on variety, processing method and initial carotene content of the fresh root.     

Bioactive compounds of cold pressed spice paprika seeds oils

The aim of present study was to report the industrial production of cold pressed spice paprika seed oil and to evaluate the effect of raw material variety and growing season factors on the fatty acid profile, tocopherol, and carotenoid contents. The spice paprika seed oils were cleanly transparent with shiny deep red color, due to the presence of considerable amount of carotenoids (629.35–848.39 µg/g). The main carotenoids were the capsantin, lutein, capsorubin, β‐carotene as free xanthophylls, mono‐ or di‐esters. The fatty acid profile demonstrated the predominant concentration (70.79–74.31%) of cis‐linoleic acid. Among the saturated fatty acid the most prevalent was the palmitic acid (11.08–12.20%), followed by the stearic acid (3.10–3.75%). The γ‐tocopherol (57.85–83.57 mg/100 g) was the major analogue in tocopherol fraction of paprika seeds oils, while the α‐tocopherol level was relatively low (4.50–16.41 mg/100 g). The oils had pleasant smell and flavor in which appeared the mild aroma of dried spice paprika.

Practical applications

The article deals with edible oil that has interesting composition from the technological and nutritional points of view. The high content of phytonutrients in the oils produced and examined in this work makes them preferred in modern nutrition programs with salads, as cooking oils, dressing and as good materials in many food industries. Owe to high antioxidant levels in paprika seed oils they can be used in cosmetic and pharmaceutical industries to increase bio‐efficiency of many products. The supposed consumption (～10 g as salad oil) can cover the 70–74% of the suggested minimum daily intake of linoleic acid and 3.7–13.6% of the vitamin E (α‐tocopherol) NRV, and 10.3–14.2% of the vitamin A (retinol equivalent) NRV. The available medicine studies have suggested the valuable properties of the γ‐tocopherol. It is worth to mention the lutein and zeaxantin levels (956.1–1332.9 µg/10 g and 106.3–207.4 µg/10 g respectively), due to their protective effect against age related macular degeneration.     

Changes in carotenoids and chlorophylls in fresh green asparagus (Asparagus officinalis L) stored under modified atmosphere packaging

Asparagus is a highly perishable product owing to its high respiratory rate, a reason why modified atmosphere packaging (MAP) has been used in order to increase the shelf‐life of fresh asparagus. Carotenoid and chlorophyll pigments are important compounds for the maintenance of both the nutritional and sensory quality of asparagus. In this study, green asparagus spears were stored under refrigeration at 2 °C for 14 days, under MAP at 2 °C for 26–33 days and under MAP at 10 °C for 20 days. Pigment profiles were determined using high‐performance liquid chromatography (HPLC), with three classes of compounds being detected, namely oxygenated carotenoids (xanthophylls), hydrocarbonated carotenoids (carotenes) and chlorophylls. The xanthophylls identified were neoxanthin, violaxanthin, lutein and zeaxanthin. Only β‐carotene was detected in the carotene fraction. In the chlorophyll pigments, three molecules were isolated, chlorophyll b, its epimer chlorophyll b′ and chlorophyll a. Also detected were the first degradation products of chlorophylls, pheophytins b and a respectively. Modified atmosphere packaging at 2 °C was found to be effective in extending the shelf‐life for up to 4 weeks and in preserving the colour of fresh asparagus. Copyright © 2004 Society of Chemical Industry     

Drying temperature,endogenous antioxidants and capsaicinoids affect carotenoid stability in paprika (red pepper spice)

The major carotenoids and carotenoid esters in Capsicum annuum L. during thermal dehydration of pepper and storage of the ground product (paprika) were examined with special focus on the role of endogenous antioxidants such as vitamins E and C and capsaicinoids, the pungent materials in hot spice red pepper. A high‐performance liquid chromatographic (HPLC) method was developed to achieve excellent separation and accurate detection of different carotenoid classes including free xanthophylls, monoesters, carotenes and di‐esters. The newly developed method included gradient elution on a reversed‐phase column with increasing proportions of isopropanol. The results indicated that presence of capsaicinoids in pungent pepper had a favourable effect on the stability of carotenoids during thermal drying. Among various di‐esters those of lutein and zeaxanthine, as well as the mono‐ester of β‐cryptoxanthin were more stable than those of capsorubin and capsanthin, pointing to the possible role of epoxide and carbonyl groups in the susceptibility of carotenoids. An Arrhenius plot for degradation of carotenoids, tocopherols and ascorbic acid as a function of drying temperature showed linear relationships for all components, with ascorbic acid being the most sensitive. During storage in a refrigerator for 3 months the paprika showed high degradation of all the examined carotenoids particularly in samples prepared from pods dried at high temperatures (90 and 100 °C). An exception was for β‐cryptoxanthin mono‐ester and violaxanthin di‐esters in a non‐pungent variety. The amounts of these carotenoids lost during storage were slightly affected by the change in drying temperature. Strong correlation was found between retention of colour in stored paprika and the initial content of ascorbic acid, but not with that of tocopherols or capsaicinoids. Copyright © 2006 Society of Chemical Industry     

Detection of orange juice adulteration by tangelo juice using multivariate analysis of polymethoxylated flavones and carotenoids

Reverse phase HPLC has been applied to quantify levels of polymethoxylated flavones and carotenoids in orange and tangelo juices. Lower levels of sinensetin and tetramethyl‐o‐scutellarein and higher levels of heptamethoxyflavone and tangeretin relative to nobiletin indicated the addition of tangelo to orange juice. β‐Cryptoxanthin and its esters, identified by positive ion electrospray mass spectrometry, were present in larger amounts relative to β‐carotene in tangelo than in orange juice. Using canonical discriminant analysis, the addition of 100 g kg^?1 tangelo to orange juice can be detected. © 2002 Society of Chemical Industry     

Possible nutritional and health‐related value promotion in orange juice preserved by high‐pressure treatment

Effects of high‐pressure treatment on the orange juice carotenoids (β‐carotene, α‐carotene, zeaxanthin, lutein and β‐cryptoxanthin) associated with nutritional (vitamin A) and health‐related (radical‐scavenging capacity) values were investigated. Various high‐pressure treatments (50–350 MPa) combined with different temperatures (30 and 60 °C) and times (2.5, 5 and 15 min) of treatment were assayed. The carotenoid content of the orange juice was analysed by HPLC‐UV, the vitamin A value was determined as retinol equivalents (RE) and the free radical‐scavenging capacity was evaluated using the DPPH (2,2‐diphenyl‐1,1‐picrylhydrazyl) radical model system. A storage study was carried out at refrigeration temperature (4 °C). High‐pressure treatments at 350 MPa produced significant increases of 20–43% in the carotenoid content of fresh orange juice (from 3.99 to 4.78–5.70 mg l^?1). A non‐uniform behaviour of high‐pressure treatments was detected. An increase in time (beyond 5 min) or temperature (above 30 °C) of treatment did not improve the amount of carotenoids extracted. Owing to better extraction of carotenoids, an increase in vitamin A value from 164 to 238 RE l^?1 (45%) was achieved with the 350 MPa/30 °C/5 min treatment. No correlation was found between the increase in carotenoid amount extracted and the free radical‐scavenging activity. © 2002 Society of Chemical Industry     

Effect of polyglycerol esters of fatty acids on physicochemical properties and stability of β‐carotene nanodispersions prepared by emulsification/evaporation method

The effects of six different polyglycerol esters of fatty acids (PGEs) as nonionic emulsifiers on the physicochemical properties and stability of β‐carotene nanoparticles in oil‐in‐water dispersions produced by an emulsification/evaporation technique were examined. The β‐carotene particle size was measured by a laser diffraction technique, and the stability and retention of β‐carotene during various preparation steps and storage were determined by HPLC. In the prepared nanodispersions the β‐carotene particle size decreased with increasing degree of glycerol polymerisation and decreasing carbon number of the fatty acid group in the PGE. The particle size of β‐carotene in nanodispersions containing polyglycerol monooleate was generally larger than that in the presence of polyglycerol monolaurate. During storage at 4 °C, although the β‐carotene content in the nanodispersions showed a significant ( P < 0.05) decrease with increasing storage period, the size distribution of β‐carotene was almost unchanged in all prepared nanodispersions. In general, the mean diameter of β‐carotene nanoparticles ranged from 85 to 132 nm. In the light of their ability to physically stabilise β‐carotene particle formation, it is suggested that PGEs with a high degree of glycerol polymerisation may be useful in the preparation of β‐carotene nanodispersions. The best stabilisation was obtained using 10 g kg^?1 decaglycerol monolaurate. Copyright © 2004 Society of Chemical Industry     

In vitro β‐Carotene Bioaccessibility and Lipid Digestion in Emulsions: Influence of Pectin Type and Degree of Methyl‐Esterification

Citrus pectin (CP) and sugar beet pectin (SBP) were demethoxylated and fully characterized in terms of pectin properties in order to investigate the influence of the pectin degree of methyl‐esterification (DM) and the pectin type on the in vitro β‐carotene bioaccessibility and lipid digestion in emulsions. For the CP based emulsions containing β‐carotene enriched oil, water and pectin, the β‐carotene bioaccessibility, and lipid digestion were higher in the emulsions with pectin with a higher DM (57%; “CP57 emulsion”) compared to the emulsions with pectin with a lower DM (30%; “CP30 emulsion”) showing that the DM plays an important role. In contrast, in SBP‐based emulsions, nor β‐carotene bioaccessibility nor lipid digestion were dependent on pectin DM. Probably here, other pectin properties are more important factors. It was observed that β‐carotene bioaccessibility and lipid digestion were lower in the CP30 emulsion in comparison with the CP57, SBP32, and SBP58 emulsions. However, the β‐carotene bioaccessibility of CP57 emulsion was similar to that of the SBP emulsions, whereas the lipid digestion was not. It seems that pectin type and pectin DM (in case of CP) are determining which components can be incorporated into micelles. Because carotenoids and lipids have different structures and polarities, their incorporation may be different. This knowledge can be used to engineer targeted (digestive) functionalities in food products. If both high β‐carotene bioaccessibility and high lipid digestion are targeted, SBP emulsions are the best options. The CP57 emulsion can be chosen if high β‐carotene bioaccessibility but lower lipid digestion is desired.     

Effects of Heat Treatment on the Carotenoid and Tocopherol Composition of Tomato

Abstract: The objective of this study was to determine the influence of thermal processing on the assessment of tocopherols and carotenoids, as well as their isomer formation in tomatoes. The sliced tomatoes were heated in an oven at 100, 130, and 160 °C for 5, 10, and 20 min, then freeze‐dried. Freeze‐dried samples were finely ground and the analysis was performed on lyophilized samples. The average concentrations of total lycopene, lutein, β‐carotene, α‐tocopherol, and γ‐tocopherol in fresh tomatoes (in 100 g dry weight) were 21.2, 1.1, 2.7, 8.0, and 2.5 mg, respectively. Oven baking of tomato at 160 °C for 20 min led to a significant increase in the apparent measurement of lycopene, β‐carotene, and α‐tocopherol content by 75%, 81%, and 32%, respectively. Heating induced isomerization of (all‐E) to various (Z) isomers of lycopene, and we found that the total (Z)‐lycopene proportion in the tomatoes increased with longer heating time. (All‐E)‐lycopene constituted 75.4% in fresh tomatoes and decreased to 52.5% in oven‐baked tomatoes (160 °C, 20 min), while (5Z)‐lycopene increased from 9.4% to 17.9% of total lycopene. However, β‐carotene release and isomerization was less influenced by the heat treatment than that of lycopene. These results suggested that thermal processes might break down cell walls and enhance the release of carotenoids and tocopherols from the matrix, as well as increase isomerization of lycopene and β‐carotene.     

Determination of Carotenoids in Fruits of Rosa sp. (Rosa Canina and Rosa Rugosa) and of Chokeberry (Aronia Melanocarpa)

Carotenoid composition of fruits of two Rosa species (Rosa canina and Rosa rugosa) and of chokeberry (Aronia melanocarpa) was studied by high performance liquid chromatography. Nine carotenoids were determined: three carotenes (lycopene, ζ-carotene, β-carotene) and six xanthophylls (neoxanthin, trans-violaxanthin, cis-violaxan-thin, 5,6-epoxylutein, lutein, β-cryptoxanthin). This high number of compounds classified these fruits among those with the greatest variety of carotenoid pigments. Quantitatively large differences occurred in the carotenoid composition of the three fruits. Rosa hips contained the highest concentrations of total carotenoids, which were mainly comprised of lycopene and βcarotene. Conversely, total xanthophylls were low. In contrast to Rosa, fruits of Aronia were lower in total carotenoids while xanthophylls composed a higher proportion.     

Phytochemicals and quality characteristics of candied paprika (Capsicum annuum L.) during storage

In this study, we prepared candied paprika from various coloured fresh paprika and compared the changes in phytochemicals and quality for 42 days by analysing carotenoids, ascorbic acids and total phenolic content, and by assessing sensory and instrumental qualities. We identified five types of carotenoids from candied red paprika (CRP) and three from candied orange paprika (COP) and candied yellow paprika (CYP). At 0‐day storage, capsanthin and β‐carotene in CRP were quantitatively analysed to 26.96 μg g^?1 fw and 3.81 μg g^?1 fw, zeaxanthin and β‐carotene in COP were 9.35 μg g^?1 fw and 4.16 μg g^?1 fw, and lutein and β‐carotene in CYP were 0.27 μg 100 g^?1 fw and 0.70 μg 100 g^?1 fw, respectively. After 42‐days storage, CRP retained approximately 68.6% carotenoids, COP retained 40%, and CYP retained 33%. Ascorbic acid and total phenolic content decreased during storage as carotenoids did. However, rates of decrease were different in different coloured paprika, especially, ascorbic acid in COP and phenolic acid in CRP were considerably conserved for 42 days. Hardness, springiness and chewiness in all samples were significantly increased by 14‐days storage and maintained until 42‐days storage, and all the sensory parameters, including colour, appearance, odour, texture, paprika flavour and overall consumer preference showed no differences until 28 days.     

Degradation of Lycopene and β‐carotene in Model Systems and in Lyophilized Guava during Ambient Storage: Kinetics,Structure, and Matrix Effects

ABSTRACT: Being highly unsaturated, carotenoids are susceptible to isomerization and oxidation during the processing and storage of food. In the present study, the degradation of acyclic lycopene and dicyclic β‐carotene in low‐moisture and aqueous model systems, as well as in lyophilized guava, during storage at ambient temperature, in the absence or presence of light, was investigated. Both carotenoids followed first order kinetics under the various conditions investigated. Lycopene degraded much faster than β‐carotene in all the model systems. In a comparison of lycopene isolated from guava, tomato, and watermelon, greater losses were observed with lycopene from tomato. Since the model system was identical in the 3 cases, these results indicated that other compounds from the food sources, co‐extracted with lycopene, might have influenced the oxidation. Light consistently and strongly promoted degradation under all conditions studied. The susceptibility of lycopene to degradation was much less in lyophilized guava than in the model systems, showing the marked protective influence of the food matrix. Loss of β‐carotene, found at a concentration of about 18 times lower than lycopene, was only slightly lower than that of lycopene in lyophilized guava, indicating that the effect of matrix and/or the initial concentration overshadowed the structural influence.     

Influence of Lipid Content in a Corn Oil Preparation on the Bioaccessibility of β‐Carotene: A Comparison of Low‐Fat and High‐Fat Samples

Some individuals with fat maldigestion have compromised digestive systems, which causes the incomplete hydrolyzation of ingested lipids within the gastrointestinal tract (GIT). We studied the influence of high‐fat (20%) and low‐fat (4%) contents on the bioaccessibility of a highly hydrophobic nutraceutical (β‐carotene) through a simulated GIT model consisting of mouth, stomach, and small intestine phases. The low‐fat and high‐fat values were chosen to simulate low‐fat and high‐fat diets. The triglycerides in the low‐fat system were fully digested, whereas those in the high‐fat system were only partially digested, thereby mimicking the digestive systems of individuals who exhibit fat maldigestion. The carotenoids were initially solubilized within oil‐in‐water nanoemulsions prepared using a nonionic surfactant (Tween 20) as emulsifier and a long‐chain triglyceride (corn oil) as the oil phase. After digestion, the total β‐carotene concentration in the filtered micelle phase was much greater for the high‐fat group (0.072 μg/mL) than for the low‐fat group (0.032 μg/mL). Conversely, the β‐carotene bioaccessibility of the high‐fat group (39%) was much lower than that of the low‐fat group (84%), which was attributed to a fraction of the carotenoids remaining in the nondigested lipid phase of the high‐fat group. These results highlight the importance of delivering hydrophobic nutraceuticals in a form where the fat phase is fully digested.     

In vitro accessibility of β‐carotene from cooked Sri Lankan green leafy vegetables and their estimated contribution to vitamin A requirement

Vitamin A deficiency is an important issue for public health in Sri Lanka, where pro‐vitamin A carotenoids from green leafy vegetables provide most of the dietary vitamin A. The objective of this study was to analyse the β‐carotene content of seven types of green leafy vegetables and calculate the contribution of one traditionally cooked portion to the recommended daily allowance (RDA) of retinol. The total amount and in vitro accessibility of β‐carotene were determined using HPLC. The in vitro method simulates the conditions in the human intestinal tract. The all‐trans‐β‐carotene content in the fresh blanched vegetables ranged from 149 µg g^?1 dry weight (DW) in leaves of Alternanthera sessilis (mukunuwanna) to 565 µg g^?1 DW in Amaranthus caudatus (thampala). One portion (100 g) of green leaves cooked without fat (coconut) only contributed from 140 to 180 µg mg^?1 of the recommended daily allowance. A. sessilis, Centella asiatica (gotukola), Spinacea oleracea (nivithi) and A. caudatus, cooked with coconut fat contributed 140–680 µg mg^?1. However, stir‐fried or ‘malluma’ preparations (with coconut products) of Sesbania grandiflora (kathurumurunga) and Manihot esculenta (manioc) may provide more than 1.59–4.37 times the RDA of retinol. These results show that not only the choice of green leaves used but also the addition of fat while cooking is of great importance. Copyright © 2005 Society of Chemical Industry     

Provitamin‐A and xanthophyll carotenoids in vegetables and food grains of nutritional and medicinal importance

This study reports carotenoid composition of vegetables (n = 56), cereals (n = 12), pulses and legumes (n = 12), analysed by HPLC. It was hypothesised that food grains, like vegetables may be good sources of carotenoids. Amongst vegetables, higher level (mg/100 g dry weight) of lutein (210–419) was detected in green/red/capsicum and yellow zucchini, whilst zeaxanthin was dominant in kenaf (4.59). β‐Carotene (mg/100 g dry weight) was higher in green capsicum and kenaf (48,159) whilst carrot, ivy gourd and green capsicum contain α‐carotene (22–110). Amongst food grains, chickpea, split red gram and flaxseed contain higher levels (μg/100 g dry weight) of lutein (185–200) whilst zeaxanthin level was highest in puffed chickpea (1.8). Red unpolished parboiled rice was richest (μg/100 g dry weight) in β‐carotene (67.6) whilst whole black gram contained higher levels of α‐carotene (52.7). Thus, results indicate that chickpea and red unpolished parboiled rice are good sources of carotenoids. These carotenoid‐rich vegetables and grains may be exploited to meet the lutein and β‐carotene requirement.