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1.
For a long time, the increased consumption of fruits and vegetables was considered critical in protecting humans against a number of diseases, such as cancer, diabetes, neurodegenerative diseases, and heart and brain vascular diseases. Presently, it is thought that the protective properties of these foods result from the presence of low-molecular antioxidants that protect the cells and their structures against oxidative damage. The alleged effect of reducing the risk for many diseases is not only due to the effect of individual antioxidants, such as α-tocopherol, ascorbic acid, or β-carotene, but also may be the result of antioxidant compounds not yet known or synergy of several different antioxidants present in fruits and vegetables. Studies on macromolecules (DNA, nucleotides, proteins) free-radical–related damage showed that diets enriched with extra servings of fruits and vegetables rich in β-carotene, tocopherols, and ascorbic acid had only limited effect on the inhibition of oxidation processes. A number of studies have shown, however, that consuming less common fruits and vegetables contribute much more to the reduction of free-radical processes, most likely because they contain a large amount of non-vitamin antioxidants, such as polyphenols and anthocyanins.  相似文献   

2.
Antioxidants can be defined on a biological basis by their ability to inhibit the oxidation of susceptible biomolecules such as proteins, lipids and DNA. There is observational evidence on an inverse association between dietary antioxidant intake and the development of chronic conditions, although randomized trials have not confirmed these results. The antioxidant potential of a biological material can be evaluated by methods categorized into three groups. The first group includes the determination of the individual antioxidants present in the investigated sample. The second focuses on ‘total antioxidant capacity’, which is considered a convenient tool for obtaining an overall estimate of the antioxidant potential of the sample. The third group involves the quantification of in vivo markers of oxidative stress, such as the products of protein, lipid and DNA oxidation. Due to differences between the assays, however, current research suggests the application of a combination of such methods for a more informative assessment of the oxidation status of the organism.  相似文献   

3.
Bovine milk proteins have emerged as a novel, dairy-based source of dietary antioxidants and a component of a nutritional strategy to maintain muscle mass during ageing. The aim of this study was to characterise the in vitro antioxidant capacity (AOC) of a milk-based protein matrix (MPM) before and after simulated gastrointestinal digestion (SGID) and determine whether plasma AOC was similarly modified in vivo following acute ingestion of the MPM in healthy 50–70 years old women. To achieve this, the AOC of the MPM was measured by the oxygen radical absorbance capacity (ORAC) assay prior to and following SGID. In parallel, plasma obtained from women prior to and for 3?h following ingestion of the MPM was analysed ex vivo for change in AOC to evaluate the translation in vivo. SGID of the MPM increased AOC by ~35% (27,365?±?2152 versus 42,592?±?2299?μmol TE/100?g dw; p?ex vivo, ingestion of the MPM increased fasting plasma AOC by ~23% (10,952?±?751 to 13,519?±?800?μmol TE/L; p?in vitro and the change in plasma AOC following ingestion of the MPM sampled ex vivo from healthy elderly women.  相似文献   

4.
Attempts have been made to use non-compositional parameters, such as total antioxidant capacity (TAC), determined by assays such as oxygen radical absorbance capacity, ferric-reducing ability of plasma, and trolox-equivalent antioxidant capacity, as surrogate markers for food quality and for monitoring food-related changes in human plasma in dietary intervention studies. Increased TAC of plasma is often indiscriminately, and therefore incorrectly, interpreted as being favorable to human health. Whether or not dietary compounds may indeed exert health effects depends on factors other than mere presence in food or body fluids. Many phytochemicals, for example, are poorly absorbed and rapidly metabolized into molecules with altered physicochemical, and therefore biological, properties. Consequently, the use of TAC assays for the in vitro assessment of antioxidant quality of food, which often is employed as a marketing argument or for the assessment of the “wholesomeness” of food, is to be discouraged.  相似文献   

5.
Abstract

Epidemiological studies have shown an inverse correlation between a fruit and vegetable-rich diet and cardiovascular diseases; this beneficial effect of fruits and vegetables is probably due to the presence of antioxidant phytochemicals. In contrast, cigarette smoking is a high risk factor for lung and heart diseases, associated with chronic oxidative stress. In the present study, the effect of the consumption of a pear, an apple and 200 ml orange juice, during 26 days, on total plasma antioxidant capacity (TAC) and lipid profile of chronic smokers and non-smoking healthy adults was analyzed. Fruit consumption increased TAC in non-smokers, but not in smokers. In non-smokers, total cholesterol, high-density lipoprotein-cholesterol, and low-density lipoprotein-cholesterol increased significantly; while in smokers, total cholesterol and low-density lipoprotein-cholesterol decreased. We may conclude fruit/juice supplementation showed different effects, depending on the smoking habit: in non-smokers it increased TAC and cholesterol; in smokers it reduced cholesterol, whithout inducing a TAC increase.  相似文献   

6.
Objective The aim of this study is to determine whether a questionnaire-based method using the Veterans Specific Activity Questionnaire (VSAQ) is a practical tool for the development of a safe exercise program to prevent a reduction in physical performance. Methods One hundred and twenty-one senior residents of Yakage, Okayama, agreed to voluntarily participate in this study. They were asked to complete a questionnaire for information on age, sex, subjective health status, exercise habits and VSAQ. We investigated the relationship between age and exercise capacity predicted by VSAQ (predicted metabolic equivalents (METs)). In addition, for 36 out of the 121 participants, we performed a 6-min walk distance test (6MD) and investigated whether its results correlate with the predicted METs. Furthermore, we prepared a modified VSAQ and examined its practicality in the evaluation of the exercise capacity of Japanese elderly (n=50). Results We found that the predicted METs correlate well with age. Habitual exercise and subjective health status did not affect the predicted METs. A significant correlation was observed between the predicted METs and the results of 6MD (r=0.56, p<0.001). We also found that certain activities included in the original VSAQ are unfamiliar to Japanese elderly; thus, we made a few modifications to the original VSAQ in order to evaluate the physical fitness of Japanese elderly. The number of inadequate answers was reduced by employing the modified VSAQ. Conclusion These findings imply that the modified VSAQ is useful in evaluating the exercise capacity of Japanese elderly adequately and is a practical scale for safe exercise.  相似文献   

7.
The stem, leaf, and root of Tinospora cordifolia (willd.) have been highly exploited for medicinal preparations; however, the nutritional and nutraceutical potential of its attractive red berries (fruits) have not so far been studied. Pigments, berberine (107.0 mg/100 g) and lycopene (50.8 mg/100 g), were identified in the deseeded fruit. Total phenol content in the fruit was 3.2 mg gallic acid equivalent/g. The IC50 of DPPH (82, and 468 ppm) and OH (100, and 1,000 ppm) scavenging activity, and the EC50 of reducing power (2,616, and 1,472 ppm) of hexane and methanol extracts, respectively, were observed. Oxygen radical absorbance capacities of the fruit extracts (150 and 300 ppm) were 1,107 and 2,614 μM trolox equivalent/g, respectively. Nutrient composition including carbohydrate (18.4%), proteins (1.5%), lipids (6%) of which ~62% was unsaturated fatty acids, vitamins like ascorbic acid (0.24 μg), niacin (0.7 mg), and tocopherols (2.4 mg) in 100 g fruits were determined. Potassium content was 1.2 g/100 g dry tissue of berries. These findings show that components of T. cordifolia fruit could be bioactive and used in food, pharmaceutical, and cosmetics.  相似文献   

8.
Free radicals play a crucial role in the pathophysiology of human diseases such as cancer, atherosclerosis, and neurodegenerative diseases, and considerable attention has been focused on functional foods (or nutraceuticals) that are able to decrease the concentrations of free radicals and consequently protect against these diseases. The present study investigated an improved quantitative assay to measure antioxidant activity using the stable and fast-reacting chromogenic indicator [2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid)] (ABTS). The ABTS-radical-scavenging activities of various antioxidants and apple extracts were measured in 96-well plates, and plots thereof were linearly interpolated, with the total radical-scavenging capacity quantified as the area under the curve. The first order of linear regression was obtained in a relationship between the absorbance reduction and various concentrations of the tested sample, and the total radical-scavenging capacity was expressed as the vitamin-C-equivalent antioxidant capacity. The advantages of this quantitative assay are that, first, it is fast, sensitive and confers little variation from experimental errors for single or mixed antioxidants; second, a large number of samples in a low quantity at a time can be run using 96-well plates.  相似文献   

9.
Bone mineral density (BMD) was measured at the middle phalange of the non-dominant hand by dual x-ray absorptiometry in a random sample of 123 women aged 19 to 63 years. Monthly intake of foods with high Oxygen Radical Absorbance Capacity (ORAC) was obtained using a Food Frequency Questionnaire (FFQ), ORAC scores were calculated, and lifestyle factors were used as confounding variables. After adjusting for age, supplement use, HRT status, physical activity, calcium intake, and ORAC intake, BMD was not predicted by ORAC. We conclude that more research is needed to measure ORAC for all free radicals in all commonly consumed fruits, vegetables, and teas in order to improve the usefulness of the FFQ in calculating approximate dietary ORAC. At this time, the potential of ORAC as a reliable predictor of health remains largely unknown, however, using currently available ORAC information, it cannot be considered a predictor of BMD.  相似文献   

10.
Abstract

Estimation of total antioxidant intake is the first step to investigate the protective effects of antioxidants on oxidative stress-mediated disease. The present study was designed to develop an algorithm to estimate total antioxidant capacity (TAC) of the US diet. TAC of individual antioxidants and 50 popular antioxidant-rich food items in the US diet were determined by 2,2'-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS) assay and the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. Theoretical TAC of foods was calculated as the sum of individual antioxidant capacities of compounds. The top 10 TAC food items in the US diet according to standard serving size were blueberry > plum > green tea > strawberry > green tea (decaffeinated) > red wine > grape juice > black tea > cherry > grape. Major contributors to TAC were the total phenolic content (r = 0.952, P < 0.001) and flavonoid content (r = 0.827, P < 0.001) of 50 foods. Theoretical TAC was positively correlated to experimental TAC of 50 foods determined by the ABTS assay (r = 0.833, P < 0.001) and the DPPH assay (r = 0.696, P < 0.001), and to TAC from the USDA database for the oxygen radical absorbance capacity (r = 0.484, P = 0.001, n = 44). The TAC database of the US diet has been established and validated. In future studies, TAC of the US diet can be linked to biomarkers of chronic disease.  相似文献   

11.
The purpose of this study was to analyze polyphenol rich beverages (vitamin enhanced waters (VEWs), fruit juices and berry juices) to determine free polyphenol concentrations and free polyphenols per Calorie based on a serving size. The Folin-Ciocalteu reagent was used in a colorimetric assay based on a catechin standard. Fruit and berry juices contained, on average, more than eight-times the concentration of free polyphenols when compared to VEWs. When Calories per serving were taken into consideration, fruit and berry juices contained more than twice the free polyphenols per Calorie.  相似文献   

12.
目的从山东省济南市采集的蚊虫标本中分离流行性乙型脑炎(乙脑)病毒(Japanese Encephalitis Virus,JEV),并确定其基因型别及前膜蛋白(Precursor Membrane,PrM)基因片段和包膜蛋白(Envelope,E)基因区段分子特征。方法对2008年采集的蚊虫标本进行病毒分离,对新分离的病毒进行血清学及分子生物学鉴定。逆转录-聚合酶链反应扩增新分离JEV的PrM、E区段核苷酸序列,测序后应用Clustal X(1.83)软件做碱基配对分析,MEGA3.1完成病毒进化分析,GENEDOS(3.2)软件完成氨基酸位点分析。结果共采集15700只蚊虫标本,包括库蚊、骚扰阿蚊、伊蚊、按蚊。随机抽取20批标本,从其中的1批三带喙库蚊标本中分离到1株病毒,经过血清学及分子生物学鉴定属于基因1型JEV。新分离JEV与减毒活疫苗株SA14-14-2株E区段核苷酸和氨基酸序列的同源性分别为88.0%和97.2%,存在14处氨基酸位点差异。结论从山东省首次分离到基因1型JEV。  相似文献   

13.
The objective of this study was to determine the effect of a lysine-deficient diet on carnitine status in adult rats and subsequently on ethanol metabolism. Adult male rats were fed either the AIN-76 diet (NS), the AIN-76 diet with wheat gluten (WG) replacing casein, the WG diet plus 0.8% L-lysine (LS), or the LS diet plus 0.5% L-carnitine (CS) for 30 days. On the 31st day the rats were given an oral dose of ethanol and blood-ethanol concentrations (BEC) were monitored for the next 8 hours. One week later the rats were given a second dose of ethanol and urine was collected until killed, 3 hours post-ethanol administration (PEA). Besides growth retardation and hypoproteinemia, BEC were significantly elevated in the WG group compared to the other group at hours 3-8 PEA. There were no significant differences in BEC between the LS and CS groups; however, their BEC were significantly higher than that of the NS group. The BEC were inversely related to liver alcohol dehydrogenase (ADH) activities which were significantly lower in WG, LS and CS groups than in the NS group. Plasma, liver and urine carnitine values were significantly higher in the CS group than in the NS, WG and LS groups, wherein the values were similar. It is concluded that the WG diet reduced ADH activity and attenuated ethanol metabolism without significantly altering blood, liver and urinary carnitines in the adult rat.  相似文献   

14.
Hydroalcoholic extracts from wheat sprouts, white tea, Morinda citrifolia and fermented papaya were analysed to determine their reducing power and antioxidant activity. The results show that the micromoles of potassium ferricyanide reduced by a quantity of extract corresponding to 1 g of the various dehydrated starting tissues are: 12.91±0.83 (wheat sprouts), 10.66±1.22 (M. citrifolia), 17.06±1.24 (white tea), and 1.05±0.09 (fermented papaya). In addition the results show a strong oxygen superoxide scavenging activity in the extracts from white tea, M. citrifolia and wheat sprouts. The activity of the fermented papaya extract is the lowest. The thin-layer chromatography and UV spectrophotometry of the extracts show in each source a mixture of antioxidant compounds probably belonging to the families of reducing glycosides and polyphenols. The chromatographic pattern of the antioxidant compounds and the UV spectrum are quite different in the various sources.  相似文献   

15.
高效液相色谱法同时测定饲料中8种抗氧化剂   总被引:1,自引:0,他引:1  
目的研究饲料中没食子酸丙酯(PG)、特丁基对苯二酚(TBHQ)、乙氧基喹(EQ)、丁基羟基茴香醚(BHA)、没食子酸辛酯(OG)、二丁基羟基甲苯(BHT)、没食子酸十二酯(DG)和正二氢愈创酸(NDGA)共8种抗氧化剂同时检测系统技术。方法样品提取后采用自动固相萃取方式;定量分析采用高效液相色谱-梯度淋洗-二极管阵列检测器方法进行检测。结果最低检测限为10 mg/kg;饲料中8种抗氧化荆含量在10 mg/kg时实验精密度为1.60%-10.46%;添加抗氧化剂的回收率在84%~106%;。结论该方法具有高效率,高灵敏度,准确度好,可靠性高等技术特点。  相似文献   

16.
贵州省是全国流行性乙型脑炎(乙脑)高发省份之一,2004-2006年乙脑发病率均排名全国第一,为此于2006年1月1日起将乙脑疫苗接种纳入免疫规划,并从2006年起连续在乙脑防治重点县或全省开展多轮次乙脑疫苗强化免疫,同时在全省范围内规范开展了乙脑病例监测.2006年8月在中国疾病预防控制中心(CDC)病毒病预防控制所脑炎室的指导和帮助下,贵州省乙脑实验室网络建立并运转.本研究评价其运转及对监测数据分析的情况.  相似文献   

17.
Ishikawa T  Widman DG  Bourne N  Konishi E  Mason PW 《Vaccine》2008,26(22):2772-2781
Multiple vaccines exist to control Japanese encephalitis (JE), but all suffer from problems. We have developed a new type of flavivirus vaccine, a pseudoinfectious virus (RepliVAX WN) that prevents West Nile virus (WNV)-induced disease. Here, we describe production of a chimeric RepliVAX (RepliVAX JE) that expresses the JE virus (JEV) prM and E proteins. Our prototype RepliVAX JE replicated poorly in cells, but blind passage produced a better-growing derivative, and analyses of this derivative allowed us to engineer a second-generation RepliVAX (RepliVAX JE.2) that grew to high titers. RepliVAX JE.2 elicited neutralizing antibodies in both mice and hamsters and provided 100% protection from a lethal challenge with JEV or WNV, respectively. These results demonstrate the utility our RepliVAX platform for producing a JE vaccine.  相似文献   

18.

Objective

The aim of this study was to investigate the link between circulating adiponectin levels and peak oxygen uptake and/or physical activity in Japanese.

Methods

A total of 528 subjects (188 men and 340 women) were enrolled in this cross-sectional study. Circulating adiponectin levels, physical activity measured by tri-axial accelerometers, peak oxygen uptake and metabolic risk parameters were evaluated. We also assessed anthropometric factors, blood pressure, blood examinations and energy intake.

Results

Circulating adiponectin levels were 6.7 ± 3.0 μg/mL in men and 11.0 ± 4.9 μg/mL in women. Circulating adiponectin levels were positively correlated with physical fitness after adjusting for age, physical activity evaluated by Σ [metabolic equivalents × h per week (METs h/w)], cigarette smoking habit and energy intake in both sexes. However, these associations were attenuated further after adjusting for body mass index including other confounding factors, especially in men. However, circulating adiponectin levels were not associated with physical activity in either sex.

Conclusion

Circulating adiponectin levels were associated with peak oxygen uptake rather than physical activity.  相似文献   

19.
目的 探讨贵州省实施流行性乙型脑炎(乙脑)疫苗强化免疫的成本效益.方法 抽样调查乙脑病例住院和非住院治疗费用、陪护费用、康复费用以及乙脑疫苗强化免疫工作中需投入的经费.计算因乙脑患病陪护人员人均减少的产值,用伤残调整寿命年指标(DALY)计算因乙脑发病造成的死亡和伤残损失,采用成本-效益分析方法,计算乙脑强化免疫的成本效益比值和产生的净效益.结果 1例乙脑病例患病后社会减少产值84.36万元.贵州省2007年开展乙脑疫苗强化免疫后发病率较1990~2006年强化前平均下降了65.30%,因采取强化免疫措施而减少发病、伤残和死亡损失的净效益为1亿2千5百余万元,成本效益比值为1∶4.88.结论 开展大规模的强化免疫,对降低乙脑发病水平效果显著,可产生较好的社会效益和经济效益.  相似文献   

20.

Objective

The aim of this study was to evaluate the link between circulating leptin levels and physical activity and/or physical fitness in apparently healthy Japanese.

Methods

A total of 85 men and 111 women who were not taking any medication were enrolled in this cross-sectional study. Circulating leptin levels, physical activity measured by tri-axial accelerometers and peak oxygen uptake were evaluated. We also assessed anthropometric data, blood pressure, blood examinations and energy intake.

Results

Circulating leptin levels were 3.2 ± 2.3 ng/mL in men and 5.9 ± 3.8 ng/mL in women. Circulating leptin levels were significantly and positively correlated with body weight, body mass index, abdominal circumference, insulin and the homeostasis model assessment index, and significantly and negatively correlated with peak oxygen uptake in both sexes. Stepwise multiple regression showed that peak oxygen uptake in men and physical activity evaluated by \(\sum {\left[ {{\text{metabolic equivalents }} \times \rm h {\text{ per week}}({\text{METs}}\;\;h/w)} \right]}\) in women were determinant factors for circulating leptin levels after adjusting for confounding factors.  相似文献   

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