The antioxidant vitamins.

This article is an attempt to study the metabolic functions of vitamin C and E together. Such a study must necessarily be imcomplete owing to the extreme richness of the literature. The increasing importance of the work on free radical reactions, their toxicity and carcinogenic action, and also their relation to the metabolism of metals, particularly iron, copper, selenium, and zinc, shows a number of metabolic pathways with which both vitamins interact. It is hoped that this article will indicate future research possibilities.     

Dietary intake of antioxidant vitamins in Russian population

Aim of present study was the getting data on dietary intake of antioxidant vitamins in Russian population in 1995-2002. The consumption of food was estimated by 24-hour recall methodology in course of Russian Longitudinal monitoring surveys of economics and health. Mean intake of vitamin A is less than recommended level and 25th procentile is near to zero. Mean and median of vitamin E intake are equal of recommended level. Dietary intake of vitamin A per 1000 kcal is maximal in group of children 0-6 year old and in adults aged 30-60 y. Nutrient density of daly diet in relation to antioxidant vitamins has maximal level in old group of population 60+ and minimal level in 6-18 year old children.     

The effect of wounding intensities on vitamins and antioxidant enhancement in potato products

The effect of wounding intensity on vitamins and antioxidant activities from potato were evaluated. Potatoes were submitted to five levels of wounding intensity (A/W) including the whole peeled potato (CK), slices, pies, shreds and chopped samples. The results showed that vitamins in potato products had different responses to the same wounding intensity. Wounding intensity significantly induced VB₁, VB₂, nicotinic acid and nicotinamide accumulation in potato products, all of which were higher than that of control at each wounding intensity. Slice cutting increased the content of VB₂, VB₅, VB₇ and VB₉ compared with the control. Shreds cutting increased the content of nicotinic acid, nicotinamide and VC compared with the control. Chopped samples significantly increased the content of VB₆, chlorogenic acid and coumaric acid. The wounding intensities also induced the accumulation of L-phenylalanin ammonia lyase (PAL) activity. Superoxide dismutase (SOD) and peroxidase (POD) activities of potato products decreased after treated by cutting process.     

Studying the mechanism of antioxidant effect of vitamins and flavonoids

In work antiradical activity of vitamins and flafonoids in relation to hydroxyl radical is established. The most antiradical activity is established for flavonoids quercetin, routin, daidzein, biochanin A and luteolin-7glucosid, Among vitamins of group in the most antiradical activity have shown vitamins B12, B2, B5, Bc. In group of fat-soluble vitamins ascorbic palmitat, vitamin K1, vitamin A and beta-carotin have shown activity above, than a known antioxidant vitamin E. The carried out work allows to draw a conclusion that antiradical activity in the relation hydroxyl radical shows the broad audience of vitamins that probably is one of aspects of their therapeutic action.     

The effects of preparation and cooking processes on vitamins and antioxidant capacity of sour and spicy potato silk

The effect of a traditional dish sour and spicy potato silk preparation and cooking process on B vitamins, phenolic profiles and antioxidant activities was investigated. Results showed that cutting of potato caused an increase in VB₁, VB₂, nicotinic acid, nicotinamide, VB₇ and VB₉. Soaking decreased the content of B vitamins and vitamin C. Blanching and rinsing caused the contents of B vitamins and vitamin C decrease compared to the control. The content of VB₁, VB₅ and VB₆ after rinsing increased compared to soaking and blanching processes. However, VB₁, nicotinamide, VB₅, VB₆ and VC decreased sharply after the stir-frying process. The content of VB₁, nicotinic acid, nicotinamide, VB₇ and VC retained the most after five steps compared to the control. In addition, there was no difference in VB₉ contents among different cooking processes compared to the control. Superoxide dismutase (SOD) exhibited a reduction rate of 95.32% and peroxidase (POD) 97.13% after the stir-frying process.     

Effect of emotional and pain stress on the level of antioxidant vitamins in the blood serum of rats

The content of ascorbic acid and alpha-tocopherol was found to be decreased in the blood of rats which had suffered an emotional pain stress. Preadaptation of the animals to hypoxia did not change the level of ascorbic acid, but it was valuable with respect to alpha-tocopherol. The emotional pain stress in the presence of adaptation to hypoxia induced in the animals reduction of the blood levels of both vitamins similar to that in the controls. The synthetic antioxidant ionol diminished stress-induced hypovitaminosis of ascorbic acid and completely prevented reduction of alpha-tocopherol level in the blood of rats after the stress.     

维生素类化合物的研究进展

该文综述了近年来维生素类化合物的研究概况,重点论述维生素A、维生素B、维生素C、维生素D和维生素E的抗氧化能力及其研究进展。饮食是一个关键的环境因素和潜在的慢性疾病控制的工具。同时,该文也呼吁重视和食用如维生素A、维生素B、维生素C、维生素D和维生素E等天然的维生素类抗氧化剂,以维持机体正常的生理功能。     

Bioavailability of vitamins

In recent years, there has been a reduction in caloric intake in populations with decreased energy demands. This has place a greater emphasis on the bioavailability of nutrients in foods because the total intake of nutrients is generally closely linked with total caloric intake. An assessment of the adequacy of dietary intakes of nutrients requires not only knowledge of the nutrient content of the foods ingested but also the extent to which the nutrient present in the diet is available for absorption and utilization. Nutrients ingested but not released during the digestive process for absorption are of no nutritional value. Bioavailability may be considered the relative absorption of a nutrient from the diet. An index of bioavailability may be extended to include the relative accumulation of a nutrient into various tissues. Various nutrients and dietary components interfere with the bioavailability of vitamins. Hence, requirements for vitamins cannot be considered independently, but must be evaluated in relationship to other nutrients and compounds consumed by an individual. An overview has been presented as to the factors that influence the bioavailability of vitamins in the human food supply.     

维生素在预防和控制贫血中的作用

<正> 全世界有超过20亿人口患有铁缺乏症,估计其中包括发展中国家三分之二的儿童和分娩期妇女。有关资料显示,患有铁缺乏症的人有半数会发展或将发展成为贫血。缺铁性贫血会损害认知功能、降低工作能力、增加母亲的发病率和死亡率、降低出生重量,以及增加胎儿和新生儿的死亡机会。     

Can the sprouting process applied to wheat improve the contents of vitamins and phenolic compounds and antioxidant capacity of the flour?

The content of tocopherols, B vitamins, as well as free soluble, soluble conjugated and insoluble bound phenolic compounds was determined in untreated, steeped and sprouted wheat grains. Antioxidant capacity of whole wheat grains and their phenolic fractions was also evaluated. Sprouting significantly increased the levels of tocopherols, niacin, riboflavin, as well as free and bound phenolic compounds improving nutritional value and antioxidant capacity of wheat grains/flour. After sprouting for 5 days, the content of total phenolics, flavonoids and ferulic acid calculated as the sum of its fractions was increased by 9.9, 30.7 and 21.6%, respectively. The content of α‐, β+γ‐ and δ‐tocopherols was increased for 3.59‐fold, 2.33‐fold and 2.61‐fold respectively, while the content of niacin, as predominant B vitamin, was increased for 1.19‐fold after sprouting. The total antioxidant capacity of untreated, steeped and sprouted whole wheat grains was 19.44, 20.37 and 22.70 mmol Trolox Eq/kg, respectively. Sprouted wheat, as a rich source of bioavailable phytochemicals, should be used to improve the nutritional quality of food.     

Industrial processing effects on chestnut fruits (Castanea sativa Mill.) 3. Minerals,free sugars,carotenoids and antioxidant vitamins

The major aim of this study was to evaluate the effects of industrial processing on the composition of minerals, free sugars, vitamins and pigments in fruits of chestnut cultivars at four stages of industrial processing (A–fresh; B–after 3 months storage at ± 0 °C and relative humidity = 90%; C–after flame peeling at 800 °–1000 °C for 1–2 s; D–after freezing in a tunnel with a CO₂ flow at ?65 °C for 15–20 min) from two harvest years. Potassium and phosphorous were predominant in the fruits of all cultivars for both harvest years. Calcium, magnesium, iron, zinc and manganese were also present in the fruits. Fruits from both harvest years had a significant content of free sugars, with sucrose predominating, and these sugars were more affected by the processing stage. Significant levels of lutein, lutein esters, γ‐tocopherol and vitamin C were also found in the chestnut fruits. Fruit carotenoids and vitamin C significantly decreased during the industrial processing.     

The relationship of antioxidant components and antioxidant activity of sesame seed oil

Although sesame seed oil contains high levels of unsaturated fatty acids and even a small amount of free fatty acids in its unrefined flavored form, it shows markedly greater stability than other dietary vegetable oils. The good stability of sesame seed oil against autoxidation has been ascribed not only to its inherent lignans and tocopherols but also to browning reaction products generated when sesame seeds are roasted. Also, there is a strong synergistic effect among these components. The lignans in sesame seed oil can be categorized into two types, i.e. inherent lignans (sesamin, sesamolin) and lignans mainly formed during the oil production process (sesamol, sesamolinol, etc.). The most abundant tocopherol in sesame seed oil is γ‐tocopherol. This article reviews the antioxidant activities of lignans and tocopherols as well as the browning reaction and its products in sesame seed and/or its oil. It is concluded that the composition and structure of browning reaction products and their impacts on sesame ingredients need to be further studied to better explain the remaining mysteries of sesame oil. © 2014 Society of Chemical Industry     

Antioxidant vitamins and colorectal cancer

Review of new publications on relationship of antioxidant vitamins status (A, E, C) and risk of colorectal cancer. The current data do not allow to conclude definitely about preventive effects of antioxidant vitamins on development of colorectal cancer. 40 ref.