Antioxidant capacity of the Spanish Mediterranean diet

The objective of this work was to determine the total dietary antioxidant capacity (TDAC) of the Spanish Mediterranean diet. The antioxidant capacity of plant foods and beverages included in National food consumption data was determined. TDAC of the Spanish diet was estimated at 6014 and 3549 μmol trolox equivalents by FRAP (ferric reducing antioxidant power) and ABTS (free radical-scavenging capacity) procedures, respectively. About 68% of TDAC came from beverages and 20% from fruits and vegetables, with a very low contribution from cereals. The capacity to inhibit in vitro LDL oxidation of plant foods and beverages was consistent with their antioxidant capacity. The recommended daily intakes of antioxidant vitamins, C and E, represent about 10% of TDAC. Total phenolics intake was estimated as 1171 mg gallic acid/person/day by the Folin–Ciocalteau method. TDAC may be a parameter to be considered in nutritional and epidemiological studies.     

Importance of a canteen lunch on the dietary intake of acrylamide

A food and drink intake survey was carried out among university students and staff members. Consumption data were collected on days when the participants took hot lunch in a university canteen. The dietary acrylamide exposure was calculated through a probabilistic approach and revealed a median intake of 0.40 microg/kg bw/day [90% confidence interval: 0.36-0.44], which is in accordance with previous exposure calculations. Biscuits (35.4%), French fries (29.9%), bread (23.5%), and chocolate (11.2%) were identified to be the main sources of dietary acrylamide. Foodstuffs consumed in between the three main meals of the day (so called snack type foods) contributed the most to the intake (42.2%). The exposure was lower in an intervention group which received free portions of fruit and vegetables, indicating that a nutritionally balanced diet may contribute to a decreased acrylamide intake. French fries had a significant impact on the acrylamide intake, due to the frequent consumption in the canteen. This demonstrates the important responsibility of caterers and canteen kitchens in the mitigation of acrylamide exposure through reduction of acrylamide in their prepared products, in particular in French fries.     

Impact of dietary polyphenols on human platelet function – A critical review of controlled dietary intervention studies

Cardiovascular disease is a chronic disease influenced by many factors, with activated blood platelets being one of them. Platelets play a central role in the formation of plaques within blood vessels, contributing to early inflammatory events. Consumption of diets rich in plant‐based products protects against the development of cardiovascular disease. Polyphenols, which are secondary plant metabolites found in a wide range of foodstuffs and beverages, may be partially responsible for these effects. Their protective properties include inhibitory effects on platelet function in vitro and in vivo. However, the bioavailability of many polyphenols is poor and it is unclear whether sufficient quantities can be obtained by dietary means to exert protective effects. Consequently, this review summarizes 25 well‐controlled human intervention studies examining the effect of polyphenol‐rich diets on platelet function. These studies report a huge variety of research methods, study designs, and study subjects, resulting in controversial assertions. One consistent finding is that cocoa‐related products, however, have platelet‐inhibiting effects when consumed in moderate amounts. To assess whether other classes of dietary polyphenols, or their metabolites, also beneficially affect platelet function requires more well‐controlled intervention studies as well as the adoption of more uniform methods to assess platelet aggregation and activation.     

Determination of dietary nitrite in patients with esophageal pre-cancerous lesion and normal people: a duplicate diet study

ABSTRACT

The goal of this study was to find the relationship between dietary nitrite and risk of esophageal cancer, and determine the amount of nitrite intake to establish the oral highest daily intake to prevent the occurrence of esophageal cancer. Duplicate portions of three-consecutive-day diets were collected from 100 patients with esophageal precancerous lesions and 100 controls. The average nitrite daily intakes for esophageal precancerous lesions and normal people were 15.72 mg/d and 11.11 mg/d. The median nitrite daily intakes for cases and controls were 8.76 mg/d and 5.33 mg/d. Positive association was observed between the risk of esophageal precancerous lesions and dietary nitrite intake (p = 0.035). An increased risk of esophageal precancerous lesions was observed for cases or controls in the highest intake quartile of nitrite (highest vs. lowest quartile odds ratio (OR) = 2.256, 95% confidence interval (CI): 1.012–5.026). These results suggest that dietary nitrite intake may influence the risk of esophageal cancer; populations with high incidence of esophageal cancer should take control of nitrite intake as one of the measures to prevent esophageal cancer.     

Assessment of the estrogenicity of the diet of a healthy female Spanish population based on its isoflavone content

Phytoestrogens are natural components of plants consumed by humans. The hormonal activity of these substances has long been known. Various in vitro tests have demonstrated the agonistic or antagonistic estrogenic activity of some phytoestrogens. The objective of this study was to estimate the supply of isoflavones in the diet of a healthy adult female population and to assess its estrogenic effect. The diet was assessed by questionnaire and the estrogenicity of the estimated isoflavone content was tested by E-screen, finding a mean total estrogenic capacity of 0.129 × 10^?10 eq.E₂ (12.9 pmol day^–1), corresponding to a daily isoflavone intake of 265.8 μg day^–1. This study offers a preliminary insight into the phytoestrogen content of the diet of a healthy active population of Spanish women. The effects of this additional hormonal burden are highly controversial, and this approach to estimating dietary phytoestrogen intake of specific populations may help to elucidate its implications for human health.     

膳食多酚的糖稳态调节作用

机体糖稳态是维持正常生命活动的重要基础,膳食多酚通过抑制碳水化合物消化酶活性、抑制葡萄糖转运和调节胰岛素抵抗等多种方式参与糖稳态调节的相关研究已经引起学界广泛关注。文章在查阅文献的基础上,对膳食多酚的种类和分布、调节糖代谢功效及作用机制进行了综述,并对膳食多酚调节糖稳态的未来发展方向进行了展望。     

Assessment of dietary intake of polychlorinated biphenyls from a total diet study conducted in Pavia, Northern Italy

The diet is considered to be the main source of body burden of polychlorobiphenyls (PCBs) in the general population. The most cost-effective and reliable way to estimate the dietary intake is based on total diet studies (TDSs). The aim of the present study was to provide a reliable estimate of recent average dietary intakes of PCBs in Northern Italy. Congener-specific analysis of PCBs was undertaken on total diet samples collected at the cafeteria of the University of Pavia. The average daily intake for total PCBs was calculated to be 0.26 µg/person day^-1. The major contributor to PCB intake was accounted for by pooled samples of bread, cereals and potatoes, followed by the protein composite, and fruit and vegetables. Although diverse dietary habits and differences in sampling and analytical procedures make comparison between different studies difficult, the daily intake of PCBs in Northern Italy can be located in the lower part of the range for values reported in the literature.     

Dietary habits of the population of rural Galicia (NW Spain): Towards the development of a dietary education programme

This study was aimed to evaluate the diet of the population of rural Galicia (NW Spain) to detect groups at risk and thereby aid the development of nutritional and dietary education policy.     

Determination of daily dietary intake of chromium by duplicate diet sampling: In vitro availability study

Intake of chromium was estimated using a duplicate diet sampling method of 108 meals (36 breakfasts, 36 lunches and 36 dinners) from the restaurant of the Hospital of Motril (S.E. Spain), corresponding to 36 consecutive days. Total and dialyzable Cr levels were measured by a validated electro-thermal atomic absorption spectrometry (ETAAS) method. A mean Cr fraction of 26 ± 12 µg meal^?1was found. The Cr uptake from meals was directly and significantly (p < 0.001) correlated with their macronutrient (carbohydrates, fibre and protein) content. Cereals and cereal by-products, legumes, dry fruits, meat, potatoes, dairy products and seafood are the primary sources of Cr. The mean Cr fraction dialyzed through dialysis tubing was 1.2 ± 1.1 µg meal^–1(4.6 ± 3.8% as mean Cr dialysability). Cr intake for breakfasts was significantly lower (p < 0.001). A correlation between the logarithmic data of total and dialyzable fraction of Cr in meals (p = 0.020) was found and dialysis ratio enhancement and, therefore, bioavailability increased with total Cr. The dialysed element content present in meals was significantly correlated with fibre, protein, Fe, Na, I, F, sodium, ascorbic acid and vitamin A levels (p < 0.05). At Fe contents in meals higher than ?7.5 mg meal^?1, the net absorption of Cr decreased significantly. The mean Cr daily dietary intake (DDI) was 77 ± 17 µg day^?1, which indicates that no adverse effects in relation to Cr nutrition (deficiency or toxicity) should occur in individuals from the area.     

卵磷脂类保健食品中PE、PC的高效液相色谱测定

为准确快速地对卵磷脂保健食品中有效成分进行定量分析 ,我们建立了卵磷脂保健食品中磷脂主要组分磷脂酰胆碱 (PC)、磷脂酰乙醇胺 (PE)的高效液相色谱测定方法。方法的日间精密度为 5 4 %～ 9 0 %;PE、PC的加标回收率分别为 83 0 %～ 10 5 6 %和 81 3%～ 86 0 %,均可满足卫生分析的要求。对 5种卵磷脂保健食品中的PC、PE的含量进行了测定 ,PC、PE的含量分别为15 2 %～ 2 4 2 %和 3 1%～ 6 1%。方法的样品前处理方法简单 ,且检测灵敏度高 ,分析速度快 ,适于在国内推广使用     

几种多酚类物质用于延长花生牛轧糖货架期的对比研究

通过测定55 ℃和45 ℃2个加速破坏温度条件下花生牛轧糖的过氧化值、酸价、菌落总数、大肠菌群4个指标,对比研究苹果多酚、葡萄籽多酚、茶多酚3种天然酚类物质对花生牛轧糖货架期的影响.结果 表明,添加0.04％的3种酚类物质都具有减缓花生牛轧糖过氧化值升高,抑制花生牛轧糖酸价增高,抑制菌落总数和大肠菌群增加的作用;在花生...     

膳食因素对茶多酚抗氧化活性的影响

研究了奶粉和甜味剂等物质对茶多酚体外抗氧化活性的影响,重点测定了对2,2-联氮-二(3-乙基-苯并噻唑-6-磺酸)二铵盐(ABTS)自由基和邻二氮菲体系中羟自由基的清除作用,结果表明:奶粉和甜味剂均会降低茶多酚对ABTS和·OH的清除作用.在ABTS体系,脱脂奶粉(70mg/mL)、全脂奶粉(70mg/mL)可使茶多酚的抑制效果分别下降53.00％和63.05％,蔗糖10％和阿斯巴甜10％使茶多酚抗氧化效果分别下降了58.59％和53.83％;针对·OH,脱脂奶粉(70mg/mL)、全脂奶粉(70mg/mL)、阿斯巴甜10％、蔗糖10％使茶多酚抗氧化效果分别下降了36.39％、24.17％、30.07％和30.77％.     

Chemistry,natural sources,dietary intake and pharmacokinetic properties of ferulic acid: A review

Ferulic acid (FA) is an abundant dietary antioxidant which may offer beneficial effects against cancer, cardiovascular disease, diabetes and Alzheimer’s disease. The impact of FA on health depends on its intake and pharmacokinetic properties. In this article, the literature pertaining to chemistry, natural sources, dietary intake and pharmacokinetic properties of FA is critically reviewed. High levels of FA are found in both free and bound forms in vegetables, fruits, cereals, and coffee. We have estimated that consumption of these foods may result in approximately 150–250 mg/day of FA intake. FA can be absorbed along the entire gastrointestinal tract and metabolized mainly by the liver. The absorption and metabolism of FA seem to be dose dependent at least in experimental settings. Further pharmacokinetic and pharmacodynamic studies are required to characterize the impact of FA on human health.     

A meta-analysis examining the relationship among dietary factors, dry matter intake, and milk and milk protein yield in dairy cows

This meta-analysis was undertaken to determine the impact of dietary components on dry matter intake (DMI), milk yield (MY), and milk protein yield (MPY) in Holstein dairy cows. Diets (n=846) from 256 feeding trials published in Volumes 73 through 83 of the Journal of Dairy Science were evaluated for nutrient composition using 2 diet evaluation models: CPM Dairy (a computer program based on the principles of the Cornell Net Carbohydrate and Protein System) and NRC (2001). Data were analyzed with and without the effect of stage of lactation as a dummy variable (<100 d in milk or > or =100 d in milk). A mixed model regression analysis was used to completely investigate the potential relationships among composition variables and DMI, MY, and MPY. Protein and carbohydrate fractions were the main components within the DMI models, and DMI played a dominant role in estimating MY and MPY. Inclusion of stage of lactation substantially improved the MY models but did not affect model fits or residual structure for DMI and MPY.     

Effects of flour storage and heat generated during milling on starch,dietary fibre and polyphenols in stoneground flours from two durum‐type wheats

In the perspective of cereal‐based functional food development, the research compared stone watermill and stone mill which differed in the heating generated during grinding (30 and 60 °C) and the effects of storage on the preservation of phytochemicals. After 6‐month storage of flour, a decrease in soluble dietary fibre (loss of 1.9–2.5 g 100 g^?1) and bound polyphenols (loss of 6.2–8.5%) was observed, while other wheat grain components remained unvaried. Comparing the milling techniques, stoneground wheat grains (60 °C) showed the highest amylose (34.7–36.9% of total starch) and resistant starch amounts (0.85–1.16% of total starch), which could be of interest for lowering Glycaemic Index. Stoneground KAMUT^® starch had higher tendency to be converted into resistant starch and it also showed the higher degree of starch damage, as compared to the durum wheat variety Claudio. The study provided suggestions for modulating the production chain with the aim of supplying added value to wheat‐based products.     

Anti-oxidant capacity of dietary polyphenols determined by ABTS assay: a kinetic expression of the results

The 2, 2^′‐Azino‐bis(3‐ethylbenz‐thiazoline‐6‐sulfonic acid) (ABTS)/Trolox equivalent anti oxidant capacity (TEAC) assay, which measures the ability of compounds to scavenge the ABTS radical cation (ABTS^?+) in relation to Trolox (TEAC) is one of the most widely used methods to determine anti oxidant capacity. Usually, the measurements are based on a fixed end‐point (4–6 min), which may not take into account the different kinetic behaviour of anti‐oxidants. The aim of this work was to propose a kinetic procedure for ABTS^?+ assay, by using the kinetic parameters ED₅₀, t_EC50 and AE [antiradical efficiency = 1/(ED₅₀ × t_EC50)], previously applied to the 2, 2‐Diphenyl‐1‐picrylhydrazyl (DPPH^?) assay. It was found that some polyphenols standards – ferulic acid, resveratrol and others‐have not yet completed their reaction at the fixed end‐point. The consideration of kinetic parameters in this method may provide a more thorough understanding of the behaviour of the anti‐oxidants. A comparison of the activity of anti‐oxidants measured by the scavenging of ABTS^?+ with that of DPPH^? was also carried out.     

Management of hyperuricemia through dietary polyphenols as a natural medicament: A comprehensive review

Hyperuricemia, a condition due to high serum uric acid level and is notorious to health. It is considered to be a potent risk factor for gout and dramatically associated in the development of many chronic diseases such as malignant tumor, cardiovascular disorders and renal failure. Modern innovative medicinal and therapeutic interventions are underlying these days to combat hyperuricemia. Previously reported studies revealed the significant impact of dietary polyphenols (e.g. anthocyanins, phenolic acids, flavonoids etc.) against hyperurecemia disorder. Dietary plant polyphenols, unlike anti- hyperuricemic agents, are not reported to have any side effects in curing hyperuricemia. The current comprehensive review figure outs the use of dietary polyphenols as a natural remedy for the management of hyperuricemia. The sources, affiliated pathways, mode of actions and factors affecting their efficiency to prevent hyperuricemia are deeply discussed in this article. Additionally, limitations and suggestions regarding previously reported studies are also highlighted.     

UV/Visible spectra of natural polyphenols: A time-dependent density functional theory study

In addition to their numerous biological activities, natural and hemisynthetic polyphenols contribute to the large variety of colours (from red to violet) in nature (e.g., fruit, vegetables, leaves and petals). In order to understand the colour variation attributed to the multitude of chemical structures of this wide class of compounds, time-dependent density functional quantum-chemical calculations at the B3P86/6-311+G(d,p) level of theory appears as a relevant and efficient tool. The UV/Vis properties of 33 polyphenols were systematically investigated, including mainly flavonoids, isoflavonoids and flavonolignans. On the basis of molecular orbital analysis we established the structure-property relationship, inter alia showing the role of π orbital (de-)localisation, mesomeric (+M) effects of hydroxyl groups and structural modification of the molecular backbone. The results might help in the future, for example, for the prediction of novel hemisynthetic compounds.