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1.
The β-carotene content of fresh and dried mangoes commonly consumed in Kenya was evaluated and converted to retinol equivalent (RE). Mango fruits of varieties Ngowe, Apple, and Tommy Atkins were harvested at mature green, partially ripe, and ripe stages and their β-carotene content analyzed. The stability of β-carotene in sun dried mangoes was also studied over 6 months under usual marketing conditions used in Kenya. The effect of using simple pretreatment methods prior to drying of mango slices on retention of β-carotene was as well evaluated. In amounts acceptable to children and women, fresh and dried mangoes can supply 50% or more of the daily required retinol equivalent for children and women. Stage of ripeness, variety, postharvest holding temperature, method of drying, and storage time of dried mango slices affected β-carotene content and consequently vitamin A value of the fruits. Apple variety grown in Machakos had the highest β-carotene. It exceeded the daily RE requirements by 11.8% and 21.5% for women and children respectively. Fresh or dried mangoes are a significant provitamin A source and should be included in food-based approaches aiming to reduce vitamin A deficiency.  相似文献   

2.
Vitamin A deficiency, which is especially widespread among children younger than age 5 years, is a major barrier to reducing child mortality rates in French-speaking West Africa. A large amount of an indigenous plant source of provitamin A carotenoids are lost to postharvest waste. For example, the postharvest loss of mangoes in the region exceeds an annual total of 100,000 metric tons. In our study, 3.75 metric tons of fresh mangoes were dried using a solar dryer to a final moisture content of 10% to 12%, yielding a total of 360 kg dried mango. The product analysis revealed 4,000+/-500 microg beta carotene/100 g and 3,680+/-150 microg beta carotene/100 g after 2 and 6 months of storage, respectively. Thus, one greenhouse solar dryer is capable of reducing postharvest mango waste by 3.75 tons providing up to 1.15 million retinol activity equivalents of dietary vitamin A. The use of this technology that requires solar energy and manpower has the potential of increasing dietary vitamin A supply by up to 27,000-fold, compared to the currently available vitamin A in the region. Moreover, mango is a fruit that is well-liked by the population in this geographic area increasing the likelihood of its ready acceptance. Reducing postharvest loss of mangoes by using greenhouse model solar dryers is a promising strategy to help combat vitamin A deficiency in French-speaking West Africa.  相似文献   

3.
BACKGROUND: Vitamin A deficiency is a public health problem in Cameroon. Data on the bioavailability of carotenoid in fruits currently consumed in Cameroon are scarce. OBJECTIVE: To assess the systemic levels of carotenoids from mangoes and papaya consumed as juice, fresh or dried slices. METHODS: Two groups of seven healthy volunteers (24 and 25 years of age; body mass index: 21 and 22 kg/m(2) respectively for subjects fed mango and papaya), were submitted to three types of meal treatments (juice, fresh and dried fruit). On the experiment day, meals served to fasting subjects during breakfast, included bread, yogurt and one of the three forms of fruit. All the treatments lasted only one day during which blood samples were collected three times; during fasting (T(0)), 4 h (T(4)) and 8 h (T(8)) after the test meal. The carotenoids and retinol contents were analysed by high-performance liquid chromatography method. RESULTS: From the major carotenoids present in papaya and mangoes, lutein, alpha-carotene and beta-carotene were found in considerable amounts. Lycopene and cryptoxanthin that were the major carotenoids in papaya samples appeared in low amounts in the chylomicrons. Significant correlations were observed between these carotenoids (at T(0), T(4) and T(8)). The three forms of consumption contributed to the rise of serum retinol levels. A comparison between the three forms revealed that papaya and mangoes consumed in form of juice or fresh fruit are the best forms because they had higher bioavailability values. CONCLUSION: Association of these different forms of consumptions could lead to a better availability of these fruits throughout the year and therefore efficiently contribute to improve vitamin A status of the population.  相似文献   

4.
Supplementation with carotene-rich fruits may be an effective and sustainable approach to prevent vitamin A deficiency. To test the effectiveness of mango supplementation, 176 Gambian children, aged 2 to 7 y, were randomly assigned to one of four treatments: 75 g of dried mango containing approximately 150 micro g retinol activity equivalents with (MF) or without (M) 5 g of fat, 5 d/wk for 4 mo or 60,000 micro g of vitamin A (A) or placebo (P) capsule at baseline. After 4 mo, plasma beta-carotene was greater in both the M (P < 0.05) and MF (P = 0.07) groups compared with the P group. After controlling for baseline plasma retinol, elevated acute phase proteins and age, plasma retinol concentrations in the A and MF, but not M, groups were higher than in the P group at the end of the study (P < 0.01). Increases in retinol concentrations, however, were small in both groups. These results support the use of dietary supplementation with dried mangoes and a source of fat as one of several concurrent strategies that can be used to help maintain vitamin A status of children in developing countries where there is a severe seasonal shortage of carotenoid-rich foods.  相似文献   

5.
《Nutrition Research》2001,21(1-2):61-70
A Guatemalan version of sweet potato flakes, called “sweet potato buds” (SPB), was created from Ipomoea batata by the drum-drying technique used to create instant mash potatoes. The yield on the first production run was 11% and that on the second production run was 13%. The amount of β-carotene per weight was concentrated from 16.5 to 42.2 μg/g from the whole sweet potato to the dried flakes. On one occasion, the β-carotene concentrations in the common variety of Guatemalan yellow-pulp sweet potato was 42.2 μg/g or 7.0 retinol equivalents (RE)/g in the SPB and on another 57.5 μg/g or 9.6 RE. Thus, a usual serving of one ounce (28 g) of SPB provides from 196 to 269 RE or 49 to 67% of the daily recommended amount. With storage in plastic or foil packaging, the β-carotene levels fell steeply, to the point of extinction within 4 months, independent of the type of barrier or the addition of food-grade antioxidants.  相似文献   

6.
Nutritional surveys carried out in Kenya report vitamin A deficiency and low levels of vitamin A adequacy of diet. Green leafy vegetables being a major source of dietary vitamin A, the current study undertook to screen some commonly consumed varieties for carotene content and to measure retention of carotene in dehydration and storage in selected species. The results indicated that some wild species, and leaves of other food crops such as cassava, bean and Irish potato that are consumed as leaf vegetables, are good sources of β-carotene, in comparison to introduced European vegetables such as cabbage and lettuce.

Levels of β-carotene retention in the selected leaf species under processing, drying and storage conditions selected for reproducibility at the rural level, indicate a potential for use of dried leaf products as dry season vitamin A supplements to the diet.  相似文献   

7.
As nutrient-dense fruits, mangoes are commonly consumed globally and are important sources of nutrients in the diet. Nonetheless, mangoes remain relatively under-consumed in the United States. The objective of the present analysis was to examine nutrient intakes, diet quality, and health outcomes using data from NHANES 2001–2018 in children and adult mango consumers (n = 291; adults n = 449) compared with mango non-consumers (children n = 28,257; adults n = 44,574). Daily energy and nutrient intakes were adjusted for a complex sample design of NHANES using appropriate weights. Mango consumption was not associated with daily energy intake, compared with non-consumption, in both children and adults. Children consuming mangoes had a significantly lower daily intake of added sugar, sodium, total fat, and a higher intake of dietary fiber, magnesium, potassium, total choline, vitamin C, and vitamin D, compared with non-consumers. In adults, mango consumers had significantly higher daily intakes of dietary fiber, magnesium, potassium, folate, vitamin A, vitamin C, and vitamin E and significantly lower intakes of added sugar and cholesterol, compared with non-consumers. Mango consumption was also associated with a better diet quality vs. mango non-consumers (p < 0.0001). Mango consumption in adolescents was associated with lower BMI z-scores, compared with non-consumption. In adults, BMI scores, waist circumference, and body weight were significantly lower only in male mango consumers when compared with mango non-consumers. The current results support that mango consumption is associated with improved nutrient intakes, diet quality, and certain health outcomes. Thus, dietary strategies that aim to increase mango consumption in the American population should be evaluated as part of future dietary guidance.  相似文献   

8.
The carotenoid content of 18 fruits (apple, banana, guava, jackfruit, kedondong, kemang, mango, mangosteen, orange, papaya, pineapple, rambutan, salak, sawo, starfruit, tangerine, red watermelon, and yellow watermelon) commonly consumed by children in West Java, Indonesia was determined using reversed-phase HPLC. These fruits were purchased in supermarkets in urban areas, small stores in rural areas, and outdoor markets. The cryptoxanthin, lycopene, and β -carotene content of these fruits are reported. Large sample-to-sample variation in the same fruit was observed in the cryptoxanthin, lycopene, and β -carotene content of these fruits. Salak and guava were found to be excellent sources (containing 140+μg retinol equivalents/100 g) of provitamin A carotenoids, and mango, red watermelon, and papaya are good sources (containing 70+μg retinol equivalents/100 g).  相似文献   

9.
生物强化高β-胡萝卜素甘薯对儿童维生素A营养干预研究   总被引:2,自引:0,他引:2  
目的研究通过生物强化技术培育的高β-胡萝卜素甘薯对儿童维生素A营养的改善作用,探讨解决人群维生素A缺乏的新途径。方法抽取四川省某县2个乡111名3~10岁维生素A缺乏和边缘性缺乏的儿童作为研究对象,按年龄、性别、血清维生素A水平随机分为干预组(n=56)和对照组(n=55),干预组每人每日食用高β-胡萝卜素甘薯(110g,β-胡萝卜素含量为52.8μg/g),对照组食用等量当地普通甘薯(β-胡萝卜素含量为2.3μg/g),干预期56d;干预前后分别对受试者进行24h膳食调查、测量身高、体重、血清维生素A含量,干预期间记录儿童膳食和患病情况。结果最终样本量为98人(干预组49人,对照组49人);干预期间儿童膳食和疾病情况无明显差异;干预后,干预组儿童血清维生素A水平(117μg/L)增加量明显高于对照组(58μg/L)(P<0.01);维生素A缺乏改善率干预组(63.3%)明显高于对照组(42.9%),两组之间差异有统计学意义(P<0.05)。结论生物强化高β-胡萝卜素甘薯能明显改善维生素A缺乏儿童的营养状况,这可能成为解决儿童维生素A缺乏问题的有效途径。  相似文献   

10.
目的为了解农村婴幼儿血清维生素A(VA)营养状况和血清类胡萝卜素水平,以及两者关系和相关影响因素而开展本研究。方法采用整群抽样方法,对山东省临沂市某镇辖区内254名6~24月龄健康婴幼儿进行健康体检和喂养状况调查。采集足背静脉血样,用高效液相色谱法测定血清视黄醇和β-胡萝卜素、α-胡萝卜素、β-隐黄素及叶黄素+玉米黄素含量。用膳食频率法回顾性调查婴幼儿最近一个月内的各类食物摄入状况,分析喂养状况与血清视黄醇和类胡萝卜素水平的关系。结果被调查婴幼儿血清视黄醇浓度平均为(0.96±0.55)μmol/L,不同月龄段间没有明显差异(P>0.05);血清VA缺乏率为40.6%,边缘性VA缺乏率为32.6%。血清β-胡萝卜素、α-胡萝卜素、β-隐黄素和叶黄素+玉米黄素浓度的平均值分别为(0.056±0.088)μmol/L、(3.3±12.1)nmol/L、(27.0±45.2)nmol/L和(0.22±0.22)μmol/L。不同月龄段儿童血清叶黄素+玉米黄素浓度存在差异(P<0.05),13~18月龄段低于6~12月龄儿童。母乳喂养和配方奶粉是影响婴幼儿血清视黄醇和β-胡萝卜素水平的主要因素。母乳喂养频率与β-胡萝卜素水平呈负相关(P<0.05),而配方粉喂养频率与血清视黄醇和除α-胡萝卜素以外的类胡萝卜素水平呈正相关(均为P<0.05);水果蔬菜喂养频率则只与血清β-胡萝卜素、α-胡萝卜素和β-隐黄素浓度呈正相关。血清视黄醇与类胡萝卜素各组分,以及类胡萝卜素各组分之间,具有显著正相关关系(均为P<0.001)。结论调查的农村婴幼儿血清VA营养状况较差,血清β-胡萝卜素、α-胡萝卜素、β-隐黄素及叶黄素+玉米黄素浓度与母乳、配方奶粉、水果蔬菜添加等喂养状况关系密切。  相似文献   

11.
目的确定菠菜及纯品油胶囊中β-胡萝卜素在学龄儿童体内的转化效率。方法选取某农村小学7~9岁儿童32名,随机分为2组,每组16名,维生素A正常和缺乏者各8名,前7天每天午饭及晚饭两组分别补充氘标记菠菜5g(含2H10-β-胡萝卜素230μg)及纯品β-胡萝卜素油胶囊(含2H8-β-胡萝卜素200μg),早饭两组均服用13C10醋酸视黄醇100μg。在实验的第3、7、8、22及28天分别采集静脉血3ml,用HPLC及GC-MS测定血清中的视黄醇浓度及标记同位素的丰度,计算菠菜及纯品油胶囊中β-胡萝卜素的转化效率。结果β-胡萝卜素油胶囊组维生素A正常和边缘缺乏的儿童β-胡萝卜素的转化率分别为2.9∶1和3.2∶1(质量比);菠菜组分别为10.1∶1和10.3∶1。结论纯品油胶囊中β-胡萝卜素的转化效率明显高于菠菜;不同维生素A营养状况的儿童β-胡萝卜素的转化效率无明显差异。  相似文献   

12.
Lutein content and β-carotene content of dried curry leaves (Murraya koenigii L. Spreng) by various methods [microwave, combo, infrared (IR), hot air oven, freeze drying, cross flow tray drying, sun and shade drying] have been evaluated. The dried leaves were treated with ice-cold acetone to get the extracts (0.69–3.64% w/w) on dry weight basis. Lutein content and β-carotene content of all these extracts were determined by high-performance liquid chromatography using an established method and found in the range of 8.2–99.5 mg/100 g and 2.9–19.2 mg/100 g, respectively. The results indicated that the microwave processed leaves contain higher levels of lutein (99.4 mg/100 g) and β-carotene (19.2 mg/100 g) compared with other drying methods. The cross flow dried (8.2 mg/100 g and 3.5 mg/100 g) and IR dried samples (23 mg/100 g and 2.9 mg/100 g) retained minimum amount of lutein and β-carotene, respectively.  相似文献   

13.
We have determined and compared the concentration levels of retinol and β-carotene in the plasma of three Sudanese women groups (displaced southern Sudanese women (DSSW), non-displaced southern Sudanese (NDSSW) and northern Sudanese women (NSW)), who were either pregnant or non-pregnant; and in their neonates (cord plasma). Plasma samples were analysed by high-performance liquid chromatography using reversed-phase column and diode-array detectors. The results revealed that retinol and β-carotene in the plasma of non-pregnant and pregnant women in the three groups were very low compared with studies reported elsewhere. Over 50% of pregnant DSSW and NDSSW had a low concentration of retinol plasma (< 0.70 μmol/L), and about 15-20% were deficient (< 0.35 μmol/L) according to World Health Organization criteria. Although the average retinol concentration in the plasma of pregnant NSW was > 0.70 μmol/L, which suggests sufficiency status, 32% showed lower levels and 10% were deficient. Plasma retinol β-carotene levels in the neonates' cords were also lower than their mothers and in comparison with other studies. These findings are in agreement with previous survey data and clinical reports, which also suggest that vitamin A deficiency is of great concern in the country. We concluded that insufficient intake of food of animal origin and repeated malarial and other parasitic diseases are the most likely causes of vitamin A deficiency.  相似文献   

14.
Despite the national vitamin A and antihelminthic prophylaxis programmes, both intestinal geo-helminths and subclinical vitamin A deficiency continue to be prevalent among children in developing countries. Studies on potential synergistic effects of vitamin A supplementation and deworming on retinol status have inconsistent results. The purpose of the present study was to investigate the impacts of low-dose β-carotene supplementation and antihelminthic therapy on serum retinol and β-carotene concentrations in preschool children of Bangladesh. Two hundred and forty-four children, known to be infected with Ascaris lumbricoides, were randomized into four treatment groups: I-IV. Group I and II received two oral doses of 400 mg of albendazole each, the first dose at baseline and the second dose after four months; Group III and IV received placebo in place of albendazole. In addition, Group I and III received 1.2 mg of β-carotene powder in capsule daily for six months, and Group II and IV received placebo in place of β-carotene. Serum retinol and β-carotene levels were measured before and after six months of the interventions. Serum retinol and β-carotene increased significantly in Group I where both antihelminthic therapy and daily β-carotene supplementation were given (p<0.05 and p<0.001 respectively). Antihelminthic therapy alone only improved serum β-carotene concentration (p<0.0001). Low-dose β-carotene supplementation, along with an antihelminthic therapy, synergistically improved vitamin A status. This finding has public-health implications for improving vitamin A status of children in developing countries.Key words: Albendazole, Antihelminthics, Ascariasis, Ascaris lumbricoides, β-carotene, Children, Deworming, Impact studies, Retinol, Vitamin A deficiency, Bangladesh  相似文献   

15.
Objective: The objective of this study was analytical assessment of the concentration of selected antioxidants as well as total antioxidant capacity of daily diets of children and adolescents from orphanages in Krakow (Poland).

Methods: Daily diets of children and adolescents were collected in 4 seasons of the year from 7 orphanages located in Krakow. The concentrations of vitamin C, β-carotene, polyphenolic compounds, and antioxidant capacity were measured.

Results: The lowest content of vitamin C in diets of children and adolescents was measured in diets collected in autumn. The estimated average requirement (EAR) was in the range 49.0%–76.4%. In winter the content of this compound was significantly higher in daily diets (113.9%–192.0% coverage of EAR) compared to the level of this nutrient in daily diets from other seasons. The content of β-carotene, lower than 50% of EAR value, calculated as the vitamin A equivalent, has been demonstrated in 4 orphanages in summer and in one in spring and autumn. The highest mean content of this antioxidant in daily diets was found in winter, when β-carotene intake met recommendations in the range 131%–368%. The mean concentration of polyphenolic compounds per year was in the range 301.5–537.5 mg/person/day. It has been observed that diets during the winter and autumn generally provide higher amounts of polyphenols than in other seasons. The highest antioxidant activity was measured in diets collected during the winter season.

Conclusions: The results indicate that the diets of children and adolescents should contain more fresh vegetables and fruits, which are good source of natural antioxidants.  相似文献   


16.
The effects of blanching with hot water at 90°C for 2 min and hot-air drying temperatures (50°C, 60°C and 70°C) on the physicochemical properties, dietary fiber compositions, antioxidant activity and hydration properties of ripe, soft persimmon peels were investigated. Blanching and drying significantly reduced the retention of antioxidant-related parameters. Although there were no significant differences in total phenolics and β-carotene content at different drying temperatures for both dried unblanched and blanched peels, dried blanched peels had higher dietary fiber compositions and swelling capacity than those of dried unblanched peels at all drying conditions. In addition, blanched peels dried at 50°C had the highest dietary fiber compositions, swelling capacity and antioxidant activity compared with those at high drying temperatures (60°C and 70°C). Therefore, blanched peels dried at 50°C is suggested to obtain better quality dietary fiber powder from persimmon peel for use in food applications or in fiber-fortified foods for health promotion.  相似文献   

17.
Experts in the field of carotenoids met at the Hohenheim consensus conference in July 2009 to elucidate the current status of β-carotene research and to summarize the current knowledge with respect to the chemical properties, physiological function, and intake of β-carotene. The experts discussed 17 questions and reached an agreement formulated in a consensus answer in each case. These consensus answers are based on published valid data, which were carefully reviewed by the individual experts and are justified here by background statements. Ascertaining the impact of β-carotene on the total dietary intake of vitamin A is complicated, because the efficiency of conversion of β-carotene to retinol is not a single ratio and different conversion factors have been used in various surveys and following governmental recommendations within different countries. However, a role of β-carotene in fulfilling the recommended intake for vitamin A is apparent from a variety of studies. Thus, besides elucidating the various functions, distribution, and uptake of β-carotene, the consensus conference placed special emphasis on the provitamin A function of β-carotene and the role of β-carotene in the realization of the required/recommended total vitamin A intake in both developed and developing countries. There was consensus that β-carotene is a safe source of vitamin A and that the provitamin A function of β-carotene contributes to vitamin A intake.  相似文献   

18.
Vitamin A intake and plasma retinol levels in healthy elderly men and women   总被引:2,自引:0,他引:2  
We examined intakes of vitamin A (diet plus supplement) and plasma retinol levels in a select group of elderly men (n = 90) and women (n = 110) on three separate occasions over a 4-y period. Median dietary levels remained at approximately 1400 retinol equivalents (RE) in men and 1250 RE in women. There were no time trends or gender differences noted in plasma retinol concentrations. Approximately 44% of the elderly men and women consumed an average of 2000 RE of a vitamin A supplement daily. Those taking supplement had a greater mean plasma retinol concentration than those not taking a supplement. This effect was greater in men than in women. A review of previous studies revealed that plasma retinol increases from a mean of approximately 35 micrograms/dL (1.22 mumol/L) at preschool age to a plateau of approximately 60 micrograms/dL (2.09 mumol/L) by age 40 y in men and 60 y in women.  相似文献   

19.
Animal studies were conducted to evaluate the influence of dietary spice compounds, piperine, capsaicin and ginger, on the absorption of orally administered β-carotene and its conversion to vitamin A. In rats maintained on these spice-containing diets for 8 weeks, concentrations of β-carotene and retinol were determined in the serum, liver and intestine 4 h after a single oral administration of β-carotene. β-Carotene concentration was significantly increased in the serum, liver and intestine of piperine- and ginger-fed rats, suggesting improved absorption of β-carotene. However, retinol concentration was not significantly changed in these animals, suggesting that the bioconversion of β-carotene to vitamin A was not similarly influenced. Between the two enzymes involved in the bioconversion of β-carotene to vitamin A, the activity of intestinal and hepatic β-carotene 15,15'-dioxygenase was either unaffected or lowered by these spice treatments. The activity of intestinal and hepatic retinal reductase was unaffected by the dietary spices. Activities of these two enzymes involved in the bioconversion of β-carotene to retinal were inhibited by the test spices in vitro, thus corroborating with the in vivo observation. Although the bioconversion of β-carotene was not promoted, increased absorption and tissue levels of β-carotene by the dietary spices may contribute to a higher antioxidant protection.  相似文献   

20.
West CE 《Nutrition reviews》2000,58(11):341-345
When the intake of foods or pharmaceutical preparations containing sufficient nutrients of adequate bioavailability are consumed, nutrient requirements are met and optimal nutritional status is maintained. Recent studies have shown that the basis for describing vitamin A activity of carotenoids overestimates the bioavailability of provitamin A carotenoids and their bioconversion to retinol (vitamin A). It is therefore proposed that instead of 6 microg from a mixed diet, 21 microg beta-carotene are required to provide 1 microg of retinol or 1 RE (retinol equivalent) of vitamin A. Based on this assumption and on data from food balance sheets, estimates of daily per capita vitamin A intake expressed in RE in Africa, South America, and Asia are reduced from 895, 599, and 667, respectively, to 371, 372, and 258, respectively. Such intakes are well below the recommended daily intake of 600 RE for adult males. A new combination of approaches will therefore have to be used to combat vitamin A deficiency rather than that used up until now.  相似文献   

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