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Objective: To determine whether high baseline dietary antioxidants and total nonenzymatic antioxidant capacity (NEAC) is associated with a lower risk of Parkinson disease (PD) in men and women, we prospectively studied 43,865 men and women from a large Swedish cohort., Methods: In the Swedish National March Cohort, 43,865 men and women aged 18-94 years were followed through record linkages to National Health Registries from 1997 until 2016. Baseline dietary vitamin E, vitamin C, and beta-carotene intake, as well as NEAC, were assessed by a validated food frequency questionnaire collected at baseline. All exposure variables were adjusted for energy intake and categorized into tertiles. Multivariable Cox proportional hazard regression models were fitted to estimate hazard ratios (HRs) with 95% confidence intervals (CIs) for PD., Results: After a mean follow-up time of 17.6 years, we detected 465 incidence cases of PD. In the multivariable adjusted model, dietary vitamin E (HR 0.68, 95% CI 0.52-0.90; p for trend 0.005) and vitamin C (HR 0.68, 95% CI 0.52-0.89; p for trend 0.004) were inversely associated with the risk of PD when comparing participants in the highest vs the lowest tertiles of exposure. No association was found with estimated intake of dietary beta-carotene or NEAC., Conclusion: Our findings suggest that dietary vitamin E and C intake might be inversely associated with the risk of PD. No association was found with dietary beta-carotene or NEAC., Classification of Evidence: This study provides Class III evidence that dietary vitamin E and C intake are inversely associated with the risk of PD., (© 2021 American Academy of Neurology.)

Purpose: Oxidative stress might play an important role in the development of osteoarthritis, but not much is known about the effect of antioxidants on osteoarthritis risk. We, therefore, aimed to investigate the effect of dietary vitamin C, E, beta-carotene, and non-enzymatic antioxidant capacity (NEAC), which measures overall antioxidant activity from the diet, on the risk of osteoarthritis., Methods: For this study 43,865 men and women from the Swedish National March Cohort (SNMC) were followed for up to 19 years. We computed dietary intake of vitamin C, E and beta-carotene using information from a Food Frequency Questionnaire (FFQ). To estimate dietary NEAC we combined the information from the FFQ with food item-specific antioxidant capacity values from an antioxidant food database. Cases of osteoarthritis were identified through the Swedish National Patient Registers. We categorized all exposure variables into sex-specific quartiles and used multivariable-adjusted Cox proportional hazards regression models to estimate hazard ratios (HRs) with 95% confidence intervals (95% CIs)., Results: In total, we observed 5976 cases of OA during 469,148 person-years of follow-up. After adjusting for potential confounders, we did not find any association between vitamin C, beta-carotene and NEAC (p-values for trend > 0.5), but a positive association was found with higher dietary vitamin E intake (HR Q4 vs Q1: 1.11; 95% CI 1.02-1.21; p for trend = 0.01) and the risk of OA., Conclusion: Our findings do not provide evidence for dietary antioxidants to protect from the development of OA, and a higher dietary vitamin E intake might even increase the risk.

Objective: Consumption of antioxidant-rich foods has been associated with a reduced risk for stroke. However, antioxidant supplementation is not recommended owing to controversial findings reported in clinical trials. The aim of this study was to better understand the effect of dietary antioxidants by investigating the effect of dietary non-enzymatic antioxidant capacity (NEAC), reflecting the antioxidant potential of the whole diet, on the risk for stroke., Methods: In the Women's Lifestyle and Health Cohort, 45 882 women 30 to 49 y of age and free from cardiovascular diseases were followed through record linkages from 1991 to 2012. Dietary NEAC was assessed by a validated food frequency questionnaire collected at baseline and categorized into quintiles. Multivariable Cox proportional hazard regression models were fitted to estimate hazard ratios with 95% confidence intervals for overall stroke and ischemic and hemorrhagic stroke separately., Results: During a mean follow-up time of 20.2 y, we detected 871 incidence cases of stroke (516 ischemic, 296 hemorrhagic, and 59 unspecified strokes). After adjusting for potential confounders, we did not find any association between dietary NEAC and stroke, either overall, or ischemic or hemorrhagic stroke (P trend > 0.05)., Conclusion: Higher dietary NEAC was not associated with any type of stroke in young and middle-aged Swedish women., (Copyright © 2020. Published by Elsevier Inc.)

Objective: Intake of antioxidants may reduce the risk for type 2 diabetes (T2D) by reducing oxidative stress. However, it is unclear whether dietary non-enzymatic antioxidant capacity (NEAC), which represents the cumulative action of dietary antioxidants and their synergistic effects in foods, is associated with decreased T2D risk. The aim of this study was to investigate the associations between dietary NEAC and T2D., Methods: The study included 64 660 adults (27 809 men and 36 851 women), 44 to 76 y of age without history of T2D in the Japan Public Health Center-based Prospective Study. Dietary NEAC was estimated using databases of NEAC measurements compiled from results for three different assays: ferric reducing-antioxidant power (FRAP), oxygen radical absorbance capacity (ORAC), and total radical-trapping antioxidant parameter (TRAP). A multiple logistic regression model was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) of self-reported physician-diagnosed T2D over 5 y with adjustment for potential confounders., Results: In all, 1191 cases of newly diagnosed T2D were reported. Dietary NEACs were not significantly associated with T2D. The multivariate-adjusted ORs were 1.04 (95% CI, 0.88-1.23; P trend  = 0.56) for FRAP, 1.11 (95% CI, 0.93-1.32; P trend  = 0.26) for ORAC, and 0.99 (95% CI, 0.84-1.18; P trend  = 0.84) for TRAP. Similar associations were observed in men and women (P interaction  = 0.46 for FRAP, 0.35 for ORAC, and 0.63 for TRAP). In stratified analyses of major prooxidant factors, no notable associations with smoking and obesity status were observed., Conclusions: This finding suggests that dietary NEAC may not be appreciably associated with T2D in Japanese adults., (Copyright © 2019. Published by Elsevier Inc.)

Background: Results from randomized trials of antioxidant supplementation have cast doubt on observational data linking diets high in antioxidants to a reduced risk of cardiovascular diseases. We hypothesized that supplementation of one or a few antioxidants might not simulate the complex actions of all antioxidants in the human diet. We therefore investigated the association between dietary Non Enzymatic Antioxidant Capacity (NEAC), reflecting the antioxidant potential of the whole diet, and the risk of myocardial infarction (MI)., Methods: In the Swedish National March Cohort, 34 543 men and women free from cardiovascular diseases and cancer were followed through record linkages from 1997 until 2010. NEAC was assessed with a validated food-frequency questionnaire at baseline. The distribution of NEAC was categorized into sex-specific quartiles. We fitted multivariable Cox proportional hazards regression models to estimate hazard ratios (HRs) with 95% confidence intervals (CIs)., Results: During a mean follow-up time of 12.7 years, we identified 1142 incident cases of MI. Successively higher quartiles (Qs) of dietary NEAC were accompanied by a monotonic trend of decreasing MI incidence, both for overall MI (HR Q4 vs Q1: 0.77; 95% CI: 0.61-0.96; p for trend = 0.008) and non-fatal MI (HR Q4 vs Q1: 0.72; 95% CI: 0.56-0.92; p for trend = 0.004). No such association was found for fatal MI., Conclusions: A diet rich in antioxidants might protect from MI.

High intakes of vegetables have been associated with a lower incidence of cardiovascular diseases (CVD). However, the effect of vegetables on immune function and antioxidant status in human studies have provided contrasting results. In the present study, after a week of run-in period, 38 subjects at risk of CVD were randomly assigned to one of the following 4-week interventions: low vegetable consumption (800 g of vegetables/week) or high vegetable consumption (4200 g of vegetables/week). Vegetables included carrots, topinambur (Jerusalem artichoke, Helianthus tuberosus ), tomatoes, red cabbage, and sweet peppers. Blood and salivary samples were collected before and after intervention periods. In addition to clinical, immunological, and antioxidant markers, leukocyte and lymphocyte expression of the gut-homing β 7 integrin was evaluated. No significant changes were detected in clinical, immunological, and antioxidant markers in biological samples, except for an increase in white blood cell count for the low vegetable consumption group ( p < 0.05). The study provides additional evidence about the uncertainty of providing a clear evidence for vegetables in modulating markers of immune function and antioxidant status. Further studies are needed in order to unravel the mechanism of effect of vegetable consumption in cardiovascular prevention.

Background: High dietary non-enzymatic antioxidant capacity (NEAC) has been inversely related to the incidence of degenerative diseases. However, few studies have investigated the validity and reproducibility of dietary NEAC estimated from a food frequency questionnaire (FFQ). We assessed the validity and reproducibility of FFQ-based dietary NEAC against a dietary record (DR)., Methods: Participants were 244 men and 253 women who completed a 28-day DR and FFQs. NEAC for each food item was estimated according to available databases of antioxidant capacity, as measured by ferric reducing-antioxidant power (FRAP), oxygen radical absorbance capacity (ORAC), and total radical-trapping antioxidant parameter (TRAP). Using Spearman's rank correlation coefficients (CCs), we assessed the validity for dietary NEACs from a 28-day DR and a FFQ, and the reproducibility for them from two FFQs administered at a 1-year interval. Additionally, joint classification and the Bland-Altman method were applied to assess agreement between the two methods., Results: Regarding validation, deattenuated CCs for the energy-adjusted overall dietary NEACs between FFQ and DR for FRAP, ORAC, and TRAP were 0.52, 0.54, and 0.52, respectively, for all subjects. Extreme miscategorization rates by joint classification analysis were 2% for FRAP and ORAC and 1% for TRAP. Regarding reproducibility, CCs between the energy-adjusted dietary NEACs from two FFQs were 0.64 for FRAP and 0.65 for ORAC and TRAP., Conclusion: The validity and reproducibility of dietary NEAC of total food from the FFQ were moderate. Estimations of dietary NEAC using FFQ would be useful in studying disease relationships by categorizing habitual dietary NEAC.

Foods rich in antioxidants have been associated with a reduced risk of myocardial infarction. However, findings from randomized clinical trials on the role of antioxidant supplementation remain controversial. It has been suggested that antioxidants interact with each other to promote cardiovascular health. We therefore investigated the association between dietary Non Enzymatic Antioxidant Capacity (NEAC), measuring the total antioxidant potential of the whole diet, and the risk of myocardial infarction. We followed 45,882 women aged 30-49 years and free from cardiovascular diseases through record linkages from 1991 until 2012. Dietary NEAC was assessed by a validated food frequency questionnaire collected at baseline. Total dietary NEAC was categorized into quintiles and multivariable Cox proportional hazard regression models were fitted to estimate hazard ratios (HR) with 95% confidence intervals (CI). During a mean follow-up time of 20.3 years we detected 657 incident cases of myocardial infarction. After adjusting for potential confounders, we found a significant 28% lower risk of myocardial infarction among women in the fourth (HR: 0.72; 95% CI 0.55-0.95) and a 40% lower risk among women in the fifth quintile (HR: 0.60, 95% CI 0.45-0.81) of dietary NEAC compared to women in the first quintile, with a significant trend (p-value < 0.001). Higher dietary NEAC is associated with a lower risk of myocardial infarction in young to middle-aged women. These findings support the hypothesis that dietary antioxidants protect from myocardial infarction and that this effect might be exerted through interactions between antioxidants.

The consumption of tea (Camellia sinensis) has been correlated with a low incidence of chronic pathologies, such as cardiovascular disease and cancer, in which oxidative stress plays a critical role. Tea catechins and theaflavins are, respectively, the bioactive phytochemicals responsible for the antioxidant activity of green tea (GT) and black tea (BT). In addition to their redox properties, tea catechins and theaflavins could have also pharmacological activities, such as the ability to lower glucose, lipid and uric acid (UA) levels. These activities are mediated by pharmacological mechanisms such as enzymatic inhibition and interaction with transporters. Epigallocatechin gallate is the most active compound at inhibiting the enzymes involved in cholesterol and UA metabolism (hydroxy-3-methyl-glutaryl-CoA reductase and xanthine oxidase respectively) and affecting glucose transporters. The structural features of catechins that significantly contribute to their pharmacological effect are the presence/absence of the galloyl moiety and the number and positions of the hydroxyl groups on the rings. Although the inhibitory effects on α-glucosidase, maltase, amylase and lipase, multidrug resistance 1, organic anion transporters and proton-coupled folate transport occur at higher concentrations than those apparent in the circulation, these effects could be relevant in the gut. In conclusion, despite the urgent need for further research in humans, the regular consumption of moderate quantities of GT and BT can effectively modulate their antioxidant capacity, mainly in people subjected to oxidative stress, and could improve the metabolism of glucose, lipid and UA., Linked Articles: This article is part of a themed section on Principles of Pharmacological Research of Nutraceuticals. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.11/issuetoc., (© 2016 The British Pharmacological Society.)

Purpose: The cellular oxidative stress (balance between pro-oxidant and antioxidant) may be a major risk factor for chronic diseases. Antioxidant capacity of human diet can be globally assessed through the dietary non-enzymatic antioxidant capacity (NEAC). Our aim was to investigate the relationship between the NEAC and all-cause and cause-specific mortality, and to test potential interactions with smoking status, a well-known pro-oxidant factor., Methods: Among the French women of the E3N prospective cohort study initiated in 1990, including 4619 deaths among 1,199,011 persons-years of follow-up. A validated dietary history questionnaire assessed usual food intake; NEAC intake was estimated using a food composition table from two different methods: ferric ion reducing antioxidant power (FRAP) and total radical-trapping antioxidant parameter (TRAP). Hazard ratio (HR) estimates and 95 % confidence intervals (CI) were derived from Cox proportional hazards regression models., Results: In multivariate analyses, FRAP dietary equivalent intake was inversely associated with mortality from all-causes (HR for the fourth vs. the first quartile: HR 4  = 0.75, 95 % CI 0.67, 0.83, p trend  < 0.0001), cancer, and cardiovascular diseases. Similar results were obtained with TRAP. There was an interaction between NEAC dietary equivalent intake and smoking status for all-cause and cardiovascular disease mortality, but not cancer mortality (respectively, for FRAP, p inter  = 0.002; 0.013; 0.113, results were similar with TRAP), and the association was the strongest among current smokers., Conclusion: This prospective cohort study highlights the importance of antioxidant consumption for mortality prevention, especially among current smokers.

Stachys palustris, well-known as marsh woundwort, is a perennial herb growing in wet environments of Europe. Its tubers, leaves and seeds are eaten raw or cooked. Alike other Stachys species, the plant is also used as a traditional remedy. Despite S. palustris has been consumed for centuries, little is known about its chemical constituents. In this work the main secondary metabolites of S. palustris from Hungary and France have been analysed. From the plant ethanolic extracts, ethanoid glucosides, isoscutellarein derivatives, caffeoyl-quinic acids and iridoids have been isolated and structurally characterized by NMR. The essential oils were analysed by GC/MS and showed (E)-phytol, fatty acids and carbonylic compounds as the most abundant compounds. The radical scavenging capacity of plant ethanolic extracts, as evaluated by the DPPH assay, was noteworthy, with IC 50 values of 92.08 - 105.42 μg/ml., (© 2017 Wiley-VHCA AG, Zurich, Switzerland.)

Objective: Both observational studies and randomized trials have shown that a diet rich in antioxidants can reduce systemic inflammation and oxidative stress, two conditions that, together with obesity and smoking, are established risk factors for stroke. However, the association between antioxidant intake and risk for stroke is poorly understood, particularly when studying possible interaction with sex. We investigated the relationship of nonenzymatic antioxidant capacity (NEAC) on risk for stroke in a large Swedish prospective cohort., Methods: The cohort study included 34 555 men and women from the Swedish National March Cohort. NEAC was assessed using a detailed food frequency questionnaire, collected at baseline. We achieved complete follow-up from enrollment in 1997 through 2010 by record linkage to nationwide registers. We identified 1186 incident cases of a first stroke, of which 860 were ischemic, 201 hemorrhagic, and 125 unspecified. We used multivariable Cox proportional hazards models to estimate adjusted hazard ratios (HR) with 95% confidence intervals (CIs)., Results: Compared with women in the lowest quartile of NEAC, women in the highest quartile had a 27% lower incidence of total stroke (HR, 0.73; 95% CI, 0.53-0.99; P trend  = 0.03) and 35% lower incidence of ischemic stroke (HR, 0.65; 95% CI, 0.43-0.99; P trend  = 0.01). Among men, the relationship between NEAC and risk for stroke was not statistically significant and all HRs were close to unity., Conclusion: Findings from the present study suggest that dietary antioxidant capacity from different foods and beverages is inversely associated with risk for stroke, more specifically ischemic stroke, in women., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Sideritis montana subsp. montana is a small annual herb occurring in countries bordering the Mediterranean and Balkan regions. The secondary metabolism of this plant has not been fully explored so far. The aim of the present study was to understand the complex mixture of secondary metabolites and the type of secretory structures. The polar constituents were isolated by column chromatography from the ethanolic extract, and their structure was elucidated by NMR and MS. The essential oil was isolated by hydrodistillation and analysed by GC/MS. The plant indumentum was studied by light and scanning electron microscopy. To complete the work, the essential oil antioxidant activity and cytotoxicity on tumor cells were evaluated by DPPH, ABTS, FRAP, and MTT methods. Four different classes of secondary metabolites were isolated, namely flavonoids, caffeoylquinic derivatives, glycosidic hydroquinones and iridoids. The essential oil was mainly characterized by sesquiterpenene hydrocarbons. Peltate and long-capitate hairs were the main sites where terpenes and polar constituents are produced. The secondary metabolites found in S. montana subsp. montana are of chemotaxonomic interest, some of them being typical of the genus Sideritis. The trichomes types observed partially differ from those described in other members of the genus Sideritis. The essential oil showed noteworthy inhibition on tumor cells., (© 2016 Wiley-VHCA AG, Zürich.)

Background: Dietary antioxidants may play an important role in the prevention of bone loss and associated fractures by reducing levels of oxidative stress. We prospectively investigated the association between dietary Non Enzymatic Antioxidant Capacity (NEAC) and the risk of hip fracture and whether this effect was modified by smoking., Method: In the Swedish National March Cohort 13,409 men and women over the age of 55 who had not experienced cancer, cardiovascular disease or hip fracture, were followed through record-linkages from 1997 through 2010. NEAC was assessed by a validated food frequency questionnaire collected at baseline. We categorized the distribution of NEAC into sex-specific quartiles and used multivariable adjusted Cox proportional hazards regression models to estimate hazard ratios (HRs) with 95% confidence intervals (95% CI)., Results: During a mean follow-up time of 12.4years, we identified 491 incident cases of first hip fracture. Subjects in the highest quartile of dietary NEAC had a 39% lower risk of incident hip fracture compared to those in the lowest quartile (HR: 0.61; 95% CI: 0.44-0.85). The association was non-linear (p for non-linearity: 0.004) with a potential threshold between the first and the second quartile and no further risk reduction at higher levels of dietary NEAC. Due to a low smoking prevalence in our study population, we had limited power to detect effect modification between dietary NEAC and smoking on a multiplicative or additive scale., Conclusion: Higher dietary NEAC intake is associated with lower risk of hip fracture in the elderly., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Background: Pancreatic cancer is one of the leading causes of cancer mortality. Diet may be associated with pancreatic cancer, but it is unknown whether specific dietary components contribute to its risk. The potential differential role of dietary antioxidants warrants further investigation., Methods: We analysed data from a case-control study of 326 pancreatic cancer cases and 652 controls conducted between 1991 and 2008 in Northern Italy. Subjects' usual diet was assessed through a validated and reproducible food frequency questionnaire. Using this information and an Italian food composition database, we calculated three indices of dietary total antioxidant capacity (TAC): Trolox equivalent antioxidant capacity (TEAC), total radical-trapping antioxidant parameter (TRAP) and ferric-reducing antioxidant power (FRAP). We estimated the odds ratios (ORs) and 95% confidence intervals (CIs) for pancreatic cancer using multiple logistic regression models conditioned on study centre, sex and age, and adjusted for major known pancreatic cancer risk factors., Results: Significant inverse associations were found for the highest tertile of TAC compared with the lowest tertile for both TEAC and FRAP. The ORs were 0.61 (95% CI 0.39-0.94, P-value for trend 0.03) and 0.63 (95% CI 0.41-0.99, P-value for trend 0.05), respectively. Total radical-trapping antioxidant parameter was inversely, but not significantly, associated with pancreatic cancer risk, with an OR of 0.78 (95% CI 0.49-1.24, P-value for trend 0.27)., Conclusions: Diet high in TAC, as measured by TEAC and FRAP, is inversely associated with pancreatic cancer risk.

Purpose: To investigate the role of the overall antioxidant activity of diet, we estimated the relation between three dietary indices of total antioxidant capacity (TAC) and endometrial cancer risk, Methods: We analyzed data from an Italian case-control study including 454 women with incident, histologically confirmed endometrial cancer, and 908 frequency-matched controls admitted to the same hospitals as cases for acute non-neoplastic conditions. A reproducible and valid food frequency questionnaire was used to assess subjects' habitual diet. TAC was measured using Italian food composition tables in terms of Ferric-reducing antioxidant power (FRAP), Trolox equivalent antioxidant capacity (TEAC), and total radical-trapping antioxidant parameter (TRAP). We computed odds ratios (OR) and corresponding 95 % confidence intervals (CIs) using conditional multiple logistic regression models, including terms for recognized endometrial cancer risk factors and total energy intake., Results: TAC was inversely related to endometrial cancer risk with ORs for the highest versus the lowest quartile of 0.69 (95 % CI 0.47-1.00) for FRAP, 0.68 (95 % CI 0.46-0.99) for TEAC, and 0.68 (95 % CI 0.47-0.98) for TRAP. The relations appeared consistent in strata of selected risk factors and decreased when considering TAC without the contribution of coffee., Conclusions: Our findings suggest a favorable role of a diet high in TAC on endometrial cancer risk, which can be partially driven by coffee consumption.

The health benefits of plant food-based diets could be related to both integrated antioxidant and antiinflammatory mechanisms exerted by a wide array of phytochemicals present in fruit, vegetables, herbs and spices. Therefore, there is mounting interest in identifying foods, food extracts and phytochemical formulations from plant sources which are able to efficiently modulate oxidative and inflammatory stress to prevent diet-related diseases. This paper reviews available evidence about the effect of supplementation with selected fruits, vegetables, herbs, spices and their extracts or galenic formulation on combined markers of redox and inflammatory status in humans., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.)

Background: Consumption of fruit and vegetables has been inversely related to gastric cancer. Two studies found that dietary antioxidant capacity has some role in explaining this association. We investigated the overall antioxidant effect from diet on gastric cancer using three measures of non-enzymatic antioxidant capacity (NEAC)., Methods: We used data from an Italian case-control study including 230 patients with incident, histologically confirmed gastric cancer, and 547 frequency matched controls admitted to the same hospitals for acute non-neoplastic diseases. A reproducible and valid food frequency questionnaire was used to assess subjects' usual diet. NEAC was measured using Italian food composition tables in terms of Trolox equivalent antioxidant capacity (TEAC), Ferric reducing-antioxidant power (FRAP) and Total radical-trapping antioxidant parameter (TRAP). We estimated the odds ratios (OR) of gastric cancer and the corresponding 95% confidence intervals (CI) using conditional logistic regression models including terms for recognized gastric cancer risk factors and total energy intake., Results: NEAC was inversely related with gastric cancer risk with ORs for the highest versus the lowest quintile of 0.54 (95%CI, 0.33-0.88) for TEAC, 0.67 (95%CI, 0.42-1.07) for FRAP and 0.57 (95%CI, 0.36-0.90) for TRAP., Conclusions: A diet rich in antioxidant capacity reduced gastric cancer risk, suggesting a high consumption of fruit and vegetables and a moderate consumption of wine and whole cereals., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

The effect of roasting on the content of flavanols and proanthocyanidins and on the antioxidant activity of cocoa beans was investigated. Cocoa beans were roasted at three temperatures (125, 135 and 145 °C), for different times, to reach moisture contents of about 2 g 100 g(-1). Flavanols and proanthocyanidins were determined, and the antioxidant activity was tested by total phenolic index (TPI), ferric reducing antioxidant power (FRAP) and total radical trapping antioxidant parameter (TRAP) methods. The rates of flavanol and total proanthocyanidin loss increased with roasting temperatures. Moisture content of the roasted beans being equal, high temperature-short time processes minimised proanthocyanidins loss. Moisture content being equal, the average roasting temperature (135 °C) determined the highest TPI and FRAP values and the highest temperature (145 °C) determined the lowest TPI values. Moisture content being equal, low temperature-long time roasting processes maximised the chain-breaking activity, as determined by the TRAP method., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Objective: Postoperative atrial fibrillation is a major cause of morbidity and mortality for stroke after cardiac surgery. Both systemic inflammation and oxidative stress play a role in the initiation of postoperative atrial fibrillation after cardiac surgery. The possible association between long-term intake of antioxidant-rich foods and postoperative atrial fibrillation incidence was examined in patients undergoing cardiac surgery., Methods: A total of 217 consecutive patients (74% were men; median age, 68.4 years) undergoing cardiac surgery, mainly coronary artery bypass grafting and valve replacement or repair, were recruited from January 2010 to September 2012. Total antioxidant capacity was measured in foods by the Trolox equivalent antioxidant capacity assay. The European Prospective Investigation into Cancer and Nutrition Food Frequency Questionnaire was used for dietary total antioxidant capacity assessment. The association among tertiles of dietary total antioxidant capacity and postoperative atrial fibrillation incidence was assessed using multivariable logistic analysis., Results: The overall incidence of total arrhythmias and postoperative atrial fibrillation was 42.4% and 38.2%, respectively. In multivariable analysis, after adjustment for age, gender, use of hypoglycemic drugs, physical activity, education, previous diagnosis of atrial fibrillation, and total energy intake, patients in the highest tertile of dietary total antioxidant capacity had a lower risk of postoperative atrial fibrillation than patients in the 2 lowest tertiles (odds ratio, 0.46; 95% confidence interval, 0.22-0.95; P = .048). A restricted cubic spline transformation confirmed the nonlinear relationship between total antioxidant capacity (in continuous scale) and postoperative atrial fibrillation (P = .023). When considering only coronary artery bypass grafting, valve replacement/repair, and combined surgeries, the protective effect on postoperative atrial fibrillation of a diet rich in antioxidants was confirmed., Conclusions: Long-term consumption of antioxidant-rich foods is associated with a reduced incidence of postoperative atrial fibrillation in patients undergoing cardiac surgery., (Copyright © 2015 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.)

Background and Aims: Oxidative processes have been related to atherosclerosis, but there is scanty information on the role of dietary antioxidants in the prevention of acute myocardial infarction (AMI)., Methods and Results: The relationship between non-enzymatic antioxidant capacity (NEAC) and the risk of nonfatal AMI was investigated in a case-control study conducted in Milan, Italy, between 1995 and 2003. Cases were 760 patients below 75 years with a first episode of AMI and controls were 682 patients admitted to hospitals for acute conditions, who completed an interviewer-administered food frequency questionnaire, tested for validity and reproducibility. NEAC (excluding coffee) was measured using Italian food composition tables in terms of ferric reducing-antioxidant power (FRAP), Trolox equivalent antioxidant capacity (TEAC) and total radical-trapping antioxidant parameter (TRAP). The odds ratios (OR) of AMI, and the corresponding 95% confidence intervals (CI), were obtained by multiple logistic regression models including terms for main risk factors of AMI and total energy intake. NEAC was inversely related with the risk of AMI. The ORs for the highest quintile compared with the lowest one were 0.41 (95% CI, 0.27-0.63) for FRAP, 0.42 (95% CI, 0.27-0.65) for TEAC and 0.41 (95% CI, 0.27-0.62) for TRAP, with significant trends in risk. The inverse relationship was apparently stronger in women and in subjects aged ≥ 60 years., Conclusions: Our results support a favorable role of dietary NEAC in the prevention of AMI, and encourage a high consumption of fruit and vegetables and a moderate consumption of wine and whole cereals., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Oxidative stress is purported to be involved in the pathogenesis of obesity-associated insulin resistance. We evaluated whether alterations in levels of circulating uric acid (UA), a systemic antioxidant, affects the following: 1) systemic (plasma and saliva) nonenzymatic antioxidant capacity (NEAC); 2) markers of systemic (urinary 8-iso-prostaglandin-F2α) and muscle (carbonylated protein content) oxidative stress; and 3) whole-body insulin sensitivity (percentage increase in glucose uptake during a hyperinsulinemic-euglycemic clamp procedure). Thirty-one obese subjects (BMI 37.1 ± 0.7 kg/m(2)) with either high serum UA (HUA; 7.1 ± 0.4 mg/dL; n = 15) or normal serum UA (NUA; 4.5 ± 0.2 mg/dL; n = 16) levels were studied; 13 subjects with HUA levels were studied again after reduction of serum UA levels to 0 by infusing a recombinant urate oxidase. HUA subjects had 20-90% greater NEAC, but lower insulin sensitivity (40%) and levels of markers of oxidative stress (30%) than subjects in the NUA group (all P < 0.05). Acute UA reduction caused a 45-95% decrease in NEAC and a 25-40% increase in levels of systemic and muscle markers of oxidative stress (all P < 0.05), but did not affect insulin sensitivity (from 168 ± 25% to 156 ± 17%, P = NS). These results demonstrate that circulating UA is a major antioxidant and might help protect against free-radical oxidative damage. However, oxidative stress is not a major determinant of insulin action in vivo.

High-fat meals (HFM) induce metabolic stress, leading to the activation of protective mechanisms, including inflammation and endogenous antioxidant defences. In the present study, we investigated the effects of antioxidant-rich fruit juice drinks on the endogenous antioxidant response induced by HFM. In a double-blind, cross-over design (10 d washout), fourteen overweight volunteers were randomly assigned to one of the following interventions: HFM+500 ml placebo beverage (HFM-PB, free from fruit); HFM+500 ml antioxidant beverage 1 (HFM-AB1; apple, grape, blueberry and pomegranate juices and grape skin, grape seed and green tea extracts); HFM+500 ml antioxidant beverage 2 (HFM-AB2; pineapple, black currant and plum juices). HFM-PB consumption increased the plasma levels of thiols (SH) (4 h, P< 0·001) and uric acid (UA) (2 h, P< 0·01) and total radical-trapping antioxidant parameter (TRAP) (4 h, P< 0·01). Following the consumption of drinks, UA production was significantly reduced with respect to placebo beverage consumption 8 h after HFM-AB2 consumption (P< 0·05). SH levels were reduced 0·5 (P< 0·05), 1 (P< 0·05) and 2 h (P< 0·01) after HFM-AB1 consumption and 2, 4 and 8 h (P< 0·05) after HFM-AB2 consumption. Plasma TRAP (2 h, P< 0·001) and urinary ferric reducing antioxidant power (0-8 h, P< 0·01) were increased by HFM-AB1 consumption, the drink with the highest in vitro antioxidant capacity, but not by HFM-AB2 consumption. In urine, UA levels were significantly increased from basal levels after the consumption of HFM-PB and HFM-AB2. However, neither of the beverages increased the urinary excretion of UA with respect to the placebo beverage. In conclusion, the increase in UA and SH levels induced by HFM as part of an endogenous antioxidant response to postprandial stress can be prevented by the concomitant ingestion of antioxidant-rich fruit juice drinks.

F2-isoprostanes are a biomarker of lipid peroxidation, and their measurement has emerged as a reliable approach to assess oxidative stress. However, dietary intervention studies in humans have provided contrasting results following supplementation with antioxidant-rich foods or supplements. In this paper, we have systematically reviewed the evidence about the effect of supplementation with antioxidant-rich foods and galenic antioxidants on isoprostanes levels in humans. Moreover, the association with nonenzymatic antioxidant capacity (NEAC), a biomarker of endogenous antioxidant status, has also been investigated. MEDLINE database was searched using the terms "(isoprostane* OR isoP OR iso-PGF OR epi-PGF) AND (intervention* OR consumption* OR administration* OR supplementation*)," with limits activated "humans" and "English." Abstracts and full texts were screened, from which were selected human intervention studies reporting isoprostanes measurement in biological fluids. The total of the studies carried out with antioxidant-rich foods and antioxidant galenic supplements was 113, reporting 154 interventions. Results suggest that dietary antioxidants modulate successfully the levels of isoprostanes in less than 45% of the interventions. A correspondence between the effect on isoprostane and NEAC has been evidenced, and this correspondence suggests the importance of measuring different biomarkers to obtain a better outline of the redox events following supplementation.

Background and Aims: The intake of antioxidant-rich foods may increase the blood levels of non enzymatic antioxidant capacity (NEAC). NEAC takes into account all antioxidants from food and synergistic effects between them. We examined the effect of a 1-year intervention with Mediterranean diet on plasma NEAC and assessed whether it was related to baseline NEAC levels., Methods and Results: Five hundred sixty-four participants at high cardiovascular risk were randomly selected from the PREDIMED (Prevención con DIeta MEDiterránea) Study, a large 3-arm randomized clinical trial. Blood NEAC levels were measured at baseline and after 1-year of dietary intervention with 1) a Mediterranean diet supplemented with virgin olive oil (MED + VOO); 2) a Mediterranean diet supplemented with nuts (MED + nuts), or 3) a control low-fat diet. Plasma NEAC was analyzed using FRAP (ferric reducing antioxidant potential) and TRAP (total radical-trapping antioxidant parameter) assays. Plasma FRAP levels increased after 1-year of intervention with MED + VOO [72.0 μmol/L (95% CI, 34.2-109.9)] and MED + nuts [48.9 μmol/L (24.3-73.5)], but not after the control low-fat diet [13.9 μmol/L (-11.9 to 39.8)]. Participants in the lowest quartile of plasma FRAP at baseline significantly increased their levels after any intervention, while those in the highest quartile decreased. Similar results occurred with TRAP levels., Conclusions: This study shows that a 1-year of MED diet intervention increases plasma TAC level in subjects at high risk for cardiovascular disease. Moreover, the effectiveness of dietary supplementation with antioxidants may be related to baseline levels of plasma NEAC., (© 2013 Elsevier B.V. All rights reserved.)

Limited epidemiological evidence suggests a protective role for plant foods rich in flavonoids and antioxidants in hepatocellular cancer (HCC) etiology. Our aim was to prospectively investigate the association between dietary intake of flavonoids, lignans and nonenzymatic antioxidant capacity (NEAC) and HCC risk. Data from the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort including 477,206 subjects (29.8% male) recruited from ten Western European countries, was analyzed. Flavonoid, lignan and NEAC intakes were calculated using a compilation of existing food composition databases linked to dietary information from validated dietary questionnaires. Dietary NEAC was based on ferric reducing antioxidant capacity (FRAP) and total radical-trapping antioxidant parameter (TRAP). Hepatitis B/C status was measured in a nested case-control subset. During a mean follow-up of 11-years, 191 incident HCC cases (66.5% men) were identified. Using Cox regression, multivariable adjusted models showed a borderline nonsignificant association of HCC with total flavonoid intake (highest versus lowest tertile, HR = 0.65, 95% CI: 0.40-1.04; p(trend) = 0.065), but not with lignans. Among flavonoid subclasses, flavanols were inversely associated with HCC risk (HR = 0.62, 95% CI: 0.39-0.99; p(trend) = 0.06). Dietary NEAC was inversely associated with HCC (FRAP: HR 0.50, 95% CI: 0.31-0.81; p(trend) = 0.001; TRAP: HR 0.49, 95% CI: 0.31-0.79; p(trend) = 0.002), but statistical significance was lost after exclusion of the first 2 years of follow-up. This study suggests that higher intake of dietary flavanols and antioxidants may be associated with a reduced HCC risk., (Copyright © 2013 UICC.)

A favorable role of fruit and vegetables on colorectal cancer risk has been related to the antioxidant properties of their components. We used data from an Italian case-control study including 1,953 patients with incident, histologically confirmed colorectal cancer (1,225 colon and 728 rectal cancers). Controls were 4,154 patients admitted to hospital for acute, non-neoplastic conditions. A reproducible and valid food frequency questionnaire was used to assess subjects' usual diet. Total antioxidant capacity (TAC) was measured using Italian food composition tables in terms of ferric reducing-antioxidant power (FRAP), Trolox equivalent antioxidant capacity (TEAC) and total radical-trapping antioxidant parameter (TRAP). We estimated the odds ratios (ORs) and the corresponding 95% confidence intervals (CIs) through multiple logistic regression models, including terms for potential confounding factors, and energy intake. TAC was inversely related with colorectal cancer risk: the OR for the highest versus the lowest quintile was 0.68 (95% CI, 0.57-0.82) for FRAP, 0.69 (95% CI, 0.57-0.83) for TEAC and 0.69 (95% CI, 0.57-0.83) for TRAP. Corresponding values, excluding TAC deriving from coffee, were 0.75 (95% CI, 0.61-0.93) for FRAP, 0.76 (95% CI, 0.61-0.93) for TEAC and 0.71 (95% CI, 0.57-0.89) for TRAP. The inverse association was apparently-though not significantly-stronger for rectal than for colon cancer. This is the first case-control study indicating consistent inverse relations between dietary TAC and colorectal cancer risk., (Copyright © 2013 UICC.)

Non-enzymatic antioxidant capacity (NEAC) represents a sensitive biomarker measuring the in vivo antioxidant potential of vegetable foods. To evaluate the effectiveness of plant-derived foods and beverages on the plasma non-enzymatic antioxidant system, we analysed all literature published upto May 2010. Data were extracted by two authors independently, and the effect size was summarised using standardised mean differences by a random-effects model. For the analysis, eighty-eight studies were included, reporting a total number of 122 interventions and involving 2890 subjects. There was overall evidence of the effectiveness of fruit, vegetables, dietary patterns based on plant foods, red wine and tea in increasing plasma NEAC. No changes were found for chocolate and fruit juices. We observed an overall effect size three times higher in subjects with risk factors when compared with healthy subjects. Total radical-trapping antioxidant parameter, oxygen radical absorbance capacity and ferric-reducing antioxidant power methods showed a similar increase in plasma NEAC following dietary supplementation, whereas Trolox equivalent antioxidant capacity did not respond to dietary supplementation. Data from the present meta-analysis show that plant-derived foods represent an effective strategy to enhance an endogenous antioxidant network in humans. This is particularly evident in the presence of oxidative stress-related risk factors.

Background and Aim: A complex relationship between immune system and metabolic pathway exists and can induce oxidative stress. The objective of this study was to design a new methodology allowing the measurement of oxidative status of leukocytes., Methods and Results: We developed a flow cytometry technique, based on C11-BODIPY 581/591 staining, to evaluate peroxidation in leukocytes. We defined the Peroxidation of Leukocytes Index Ratio (PLIR) as the ratio between the damage after AAPH-induced and PMA-induced peroxidation, using Trolox as standard antioxidant. Sensitivity of the method was assessed by correlating results with plasma antioxidant capacity (TRAP and FRAP), levels of endogenous antioxidants (uric acid and sulfhydryls) and markers of metabolic status (cholesterol, triglycerides, glucose and insulin). PLIR measures the ratio between the resistance to exogenous and endogenous ROS injury, independently from baseline level of oxidation, which was directly correlated with plasma cholesterol on lymphocytes (0.738, p=0.029), monocytes (0.691, p=0.047) and neutrophils (0.690, p=0.047). PLIR of lymphocytes was inversely correlated with uric acid (-0.810, p=0.009) and FRAP (-0.738, p=0.029) levels. On the other hand, PLIR of monocytes was directly correlated with the total scavenger antioxidant capacity attributable to nutritional antioxidants (0.738, p=0.029), calculated as the difference between TRAP and the contribution of uric acid and sulfhydryls to its value., Conclusions: This study reports a feasible and reproducible new flow cytometry assay for assessing the leukocytes redox status. PLIR discriminates between reducing and scavenger activities and is able to appreciate the potentially dangerous effect of uric acid on innate immune response., (Copyright © 2013 Elsevier B.V. All rights reserved.)

A high intake of dietary antioxidant compounds has been hypothesized to be an appropriate strategy to reduce gastric cancer (GC) development. We investigated the effect of dietary total antioxidant capacity (TAC) in relation to GC in the European Prospective Investigation into Cancer (EPIC) study including 23 centers in 10 European countries. A total of 521,457 subjects (153,447 men) aged mostly 35-70 years old, were recruited largely between 1992 and 1998. Ferric reducing antioxidant potential (FRAP) and total radical-trapping antioxidant parameter (TRAP), measuring reducing and chain-breaking antioxidant capacity were used to measure dietary TAC from plant foods. Dietary antioxidant intake is associated with a reduction in the risk of GC for both FRAP (adjusted HR 0.66; 95%CI (0.46-0.95) and TRAP (adjusted HR 0.61; 95%CI (0.43-0.87) (highest vs. lowest quintile). The association was observed for both cardia and noncardia cancers. A clear effect was observed in smokers with a significant reduction in GC risk for the fifth quintile of intake for both assays (highest vs. lowest quintile: adjusted HR 0.41; 95%CI (0.22-0.76) p for trend <0.001 for FRAP; adjusted HR 0.52; 95%CI (0.28-0.97) p for trend <0.001 for TRAP) but not in nonsmokers. In former smokers, the association with FRAP intake was statistically significant (highest vs. lowest quintile: adjusted HR 0.4; 95%CI (0.21-0.75) p < 0.05); no association was observed for TRAP. Dietary antioxidant capacity intake from different sources of plant foods is associated with a reduction in the risk of GC., (Copyright © 2011 UICC.)

Dietary polyphenols have been shown to scavenge free radicals, modulating cellular redox transcription factors in different in vitro and ex vivo models. Dietary intervention studies have shown that consumption of plant foods modulates plasma Non-Enzymatic Antioxidant Capacity (NEAC), a biomarker of the endogenous antioxidant network, in human subjects. However, the identification of the molecules responsible for this effect are yet to be obtained and evidences of an antioxidant in vivo action of polyphenols are conflicting. There is a clear discrepancy between polyphenols (PP) concentration in body fluids and the extent of increase of plasma NEAC. The low degree of absorption and the extensive metabolism of PP within the body have raised questions about their contribution to the endogenous antioxidant network. This work will discuss the role of polyphenols from galenic preparation, food extracts, and selected dietary sources as modulators of plasma NEAC in humans.

Background/objectives: Antioxidant-rich foods may favorably influence lung function. We examined possible associations between the total dietary antioxidant capacity (TAC) and pulmonary function in a healthy Italian population., Subjects/methods: Until May 2009, 22,300 persons were randomly recruited from the general population in the Moli-sani project. A sample only including healthy women (5824) and men (5848) was analyzed. TAC was measured in foods by three different assays and the ferric reducing-antioxidant power (FRAP) assay was selected as the better indicator of dietary TAC. The European Investigation into Cancer and Nutrition Food Frequency Questionnaire was used for dietary assessment. The association between quintiles of dietary FRAP and pulmonary indexes was assessed using analysis of variance separately for men and women., Results: After adjustment for confounders, women in the highest quintile of FRAP intake had +39 ml forced expiratory volume in the first second (FEV(1)) and +54 ml forced vital capacity, compared with those in the lowest quintile (P for trend ≤0.006). Stratified analysis showed that this relationship only occurred in women who were premenopausal/never smokers. In this subgroup, the observed effect of higher FRAP intake on FEV(1) was equivalent to an improvement in pulmonary age of 3.3 years. In men, all significant associations between pulmonary function and TAC were lost after adjustment for confounding., Conclusions: Dietary TAC may have a favorable role in respiratory health, particularly in premenopausal/never smoker women.

It has been suggested that antioxidants attenuate oxidative stress and prevent oxidative stress-related diseases. Paradoxically, randomised controlled trials (RCT) using pharmacological doses of antioxidant supplements have demonstrated harmful effects in smokers. The aim of the present study was to test the compliance, tolerability and safety of two food-based antioxidant-rich diets in smokers. One of the diets provided antioxidants at levels similar to that used in RCT using supplements which previously have generated harmful effects. The present study followed a randomised, parallel-arm dietary intervention for 8 weeks (n 102) in male smokers (age ≥ 45 years). Participants were randomised to either antioxidant-rich diet, kiwi fruit or control groups. The antioxidant-rich foods provided about 300 mmol antioxidants/week from a wide range of plant-based food items. The kiwi fruit group consumed three kiwi fruits/d. Compliance to both diets was good. Only mild, undesirable events were reported by a minority of the participants. The safety of both diets was demonstrated as no potentially harmful or pro-oxidative effects were observed. In the antioxidant-rich diet group, the mean intake of antioxidants increased from 30 mmol/d at baseline to 62 mmol/d during the intervention. In conclusion, we have demonstrated that male smokers can comply with two food-based antioxidant-rich diets. Furthermore, the present study is the first to demonstrate the tolerability and safety of dietary antioxidants at levels similar to dosages provided in RCT using supplements. Such diets may be useful in future studies investigating whether dietary antioxidants may reduce oxidative stress and related diseases.

Human studies provide evidence for beneficial effects of polyphenol-rich foods on cardiovascular health. The antioxidant activity of polyphenols potentially explains these effects, but is the antioxidant activity a reliable predictor for these effects? An International Life Sciences Institute Europe working group addressed this question and explored the potential of antioxidant claims for polyphenols in relation to cardiovascular health by using the so-called Process for the Assessment of Scientific Support for Claims on Foods project criteria. In this process, analytical aspects of polyphenols, their occurrence in foods, dietary intake, and bioavailability were reviewed. Human studies on polyphenols and cardiovascular health were reviewed together with methods for biomarkers of oxidative damage and total antioxidant capacity (TAC). In retrospective studies, F2-isoprostanes and oxidized LDL, the most reliable biomarkers of lipid peroxidation, and measures for TAC showed the expected differences between cardiovascular disease patients and healthy controls, but prospective studies are lacking, and a causal relationship between these biomarkers and cardiovascular health could not be established. Therefore, the physiological relevance of a potential change in these biomarkers is unclear. We found limited evidence that some types of polyphenol-rich products modify these biomarkers in humans. A direct antioxidant effect of polyphenols in vivo is questionable, however, because concentrations in blood are low compared with other antioxidants and extensive metabolism following ingestion lowers their antioxidant activity. Therefore, the biological relevance of direct antioxidant effects of polyphenols for cardiovascular health could not be established. Overall, although some polyphenol-rich foods exert beneficial effects on some biomarkers of cardiovascular health, there is no evidence that this is caused by improvements in antioxidant function biomarkers (oxidative damage or antioxidant capacity).

Background: To study the impact of the dietary antioxidant quercetin on risk of gastric adenocarcinoma., Patients and Methods: Using data from a large Swedish population-based case-control study of gastric cancer (505 cases and 1116 controls), we studied the association between quercetin and risk of anatomic (cardia/noncardia) and histological (intestinal and diffuse) subtypes of gastric cancer., Results: We found strong inverse associations between quercetin and the risk of noncardia gastric adenocarcinoma, with an adjusted odds ratio (OR) of 0.57 (95% confidence interval 0.40-0.83) for the highest quintile (≥11.9 mg) of daily quercetin intake relative to the lowest quintile of intake (<4 mg quercetin/day), supported by a significant decreasing linear trend (P value < 0.001). Similar findings were observed for the intestinal and diffuse subtype. For cardia cancer, we found a less evident and nonsignificant inverse relationship. The protection of quercetin appeared to be stronger among female smokers, with the OR leveled of at values <0.2 in quintiles 3-5 (>6 mg quercetin/day)., Conclusions: High dietary quercetin intake is inversely related to the risk of noncardia gastric adenocarcinoma, and the protection appears to be particularly strong for women exposed to oxidative stress, such as tobacco smoking.

A large body of evidence has described the antioxidant properties of phytochemicals such as PolyPhenols (PP) in different in vitro and ex vivo models. PP have been shown to scavenge oxygen and nitrogen derived free radicals, modulating antioxidant enzymes and cellular redox transcription factors. Dietary intervention studies have shown that consumption of plant foods modulate plasma Non Enzymatic Antioxidant Capacity (NEAC), biomarker of endogenous antioxidant network, in human subjects. However the identification of the molecules responsible for this effect is far to be obtained and evidences of an antioxidant in vivo action of PP are contrasting. There is a clear discrepancy between PP concentration in body fluids and the extent of increase of plasma NEAC. The low degree of absorption and the extensive metabolism of PP within the body have raised questions about their contribution to the in vivo antioxidant network. The available evidence from human intervention studies on the role of plant foods as modulators of plasma/serum NEAC and the involvement of PP will be presented and critically discussed.

In a randomized cross-over study, 15 healthy volunteers consumed 500 mL of green tea (GTFT) with different solid contents (1.4, 1.6, 1.8 and 2.0 g/L) to induce a dose-response effect on plasma antioxidant capacity. Ingestion of GTFT 2.0 g/L significantly increased plasma reducing power (ferric reducing antioxidant power, FRAP) at 1 h (+2.9%; p<0.01), 2 h (+2.5%; p<0.05) and 4 h (+3.6%; p<0.01). GTFT 1.8 g/L showed statistical significance at 1 h (+4.3%; p<0.01) and 2 h (+4.4%; p<0.01), whereas GTFT 1.6 g/L was effective only at 1 h (+2.9%; p<0.01) and GTFT 1.4 g/L did not induce any changes. The maximum peak of increase in plasma FRAP for different GTFTs was clearly correlated with in vitro FRAP (R=0.778). GTFT 2.0 g/L significantly increased plasma antioxidant potential (total radical-trapping antioxidant parameter) at 1 h (+8.4%; p<0.01), 2 h (+4.4%; p<0.05) and 4 h (+5.9%; p<0.01). The effect of GTFT 1.8 g/L was evident at 1 h (+5.2%; p<0.05) and 2 h (+4.6%; p<0.05) but not at 4 h. No changes in plasma total radical-trapping antioxidant parameter were detected for GTFT at 1.6 and 1.4 g/L. An evidence for a linear correlation between GTFT antioxidant content and the extent of the antioxidant effect in vivo has been provided.

Secondary metabolite isolation and analysis of Plumbago europaea L. (Plumbaginaceae) is the aim of this work, which is included in a project of our groups on spontaneous and endemic Sardinian species. Plumbago europaea is the only specie of the genera that grows wild in Italy. Metabolites from leaves and roots of this specie were compared. Moreover, at present, literature on the phytochemical characterisation of P. europaea is poor. Plumbagin was isolated in both of the samples analysed, confirming its nature in the Plumbaginaceae family as chemotaxonomic marker of the Plumbaginae tribe. In this work, hydroplumbagin-4-O-glucoside and myricetin-3-O-rhamnoside are isolated for the first time in the genus.

Objective: We tested in mice the hypothesis that ingestion of infusions of green tea, white tea, or the aromatic plant Pelargonium purpureum increases total antioxidant capacity (TAC) of plasma and organs., Methods: Twenty-five mice were randomly assigned to five groups, each of which received by gavage 0.1 mL of infusion from green tea, white tea, or P. purpureum (8 g/100 mL of water) or catechin (0.01 g/100 mL) or water for 5 consecutive days. On the fifth day the animals were euthanized. Blood was taken by heart puncture and the heart, lungs, liver, spleen, kidney, and brain were removed. TAC was measured in plasma and in all organ homogenates with the ferric reducing antioxidant power assay and in selected organ homogenates by the total radical-trapping antioxidant parameter assay., Results: Green tea and P. purpureum increased TAC in the plasma and lungs, whereas green tea, white tea, and catechin increased TAC in heart homogenates. No effect was observed on the liver, brain, spleen, and kidney homogenates in comparison with the water control with the ferric reducing antioxidant power assay or the total radical-trapping antioxidant parameter assay., Conclusion: These results suggest that green tea, white tea, and P. purpureum exhibit antioxidant effects in vivo that may be observed not only in plasma but also in some organs.

The antioxidant properties of dietary phenolics are believed to be reduced in vivo because of their affinity for proteins. In this study we assessed the bioavailability of phenolics and the in vivo plasma antioxidant capacity after the consumption of blueberries (Vaccinium corymbosum L.) with and without milk. In a crossover design, 11 healthy human volunteers consumed either (a) 200 g of blueberries plus 200 ml of water or (b) 200 g of blueberries plus 200 ml of whole milk. Venous samples were collected at baseline and at 1, 2, and 5 h postconsumption. Ingestion of blueberries increased plasma levels of reducing and chain-breaking potential (+6.1%, p<0.001; +11.1%, p<0.05) and enhanced plasma concentrations of caffeic and ferulic acid. When blueberries and milk were ingested there was no increase in plasma antioxidant capacity. There was a reduction in the peak plasma concentrations of caffeic and ferulic acid (-49.7%, p<0.001, and -19.8%, p<0.05, respectively) as well as the overall absorption (AUC) of caffeic acid (p<0.001). The ingestion of blueberries in association with milk, thus, impairs the in vivo antioxidant properties of blueberries and reduces the absorption of caffeic acid.

As well as tables of food composition, total antioxidant capacity (TAC) databases--developed in past years for investigating health effects of antioxidant-rich foods in epidemiological and nutritional studies--have been created on the basis of analytical data from raw plant material. However, most vegetables are commonly cooked before consumption. With the aim of completing a previously developed TAC database, the effect of the major domestic practices (i.e. boiling, pan-frying and deep-frying) on the TAC of commonly consumed cooked vegetables was evaluated. Based on dry weight, boiling generally resulted in positive TAC changes whereas a general negative effect on the TAC was observed in pan-fried vegetables. Deep-frying produced a TAC increase of potato, artichoke and aubergine but a TAC reduction of mushroom and onion. The present study clearly indicates that cooking is not always a detrimental process when the TAC is used as an index to evaluate the nutritional characteristics of vegetables.

Background: Total antioxidant capacity (TAC) provides an assessment of antioxidant activity and synergistic interactions of redox molecules in foods and plasma., Objective: We investigated the validity and reproducibility of food-frequency questionnaire (FFQ)-based TAC estimates assessed by oxygen radical absorbance capacity (ORAC), total radical-trapping antioxidant parameters (TRAP), and ferric-reducing antioxidant power (FRAP) food values., Design: Validity and reproducibility were evaluated in 2 random samples from the Swedish Mammography Cohort. Validity was studied by comparing FFQ-based TAC estimates with one measurement of plasma TAC in 108 women (54-73-y-old dietary supplement nonusers). Reproducibility was studied in 300 women (56-75 y old, 50.7% dietary supplement nonusers) who completed 2 FFQs 1 y apart., Results: Fruit and vegetables (mainly apples, pears, oranges, and berries) were the major contributors to FFQ-based ORAC (56.5%), TRAP (41.7%), and FRAP (38.0%) estimates. In the validity study, whole plasma ORAC was correlated (Pearson) with FFQ-based ORAC (r = 0.35), TRAP (r = 0.31), and FRAP (r = 0.28) estimates from fruit and vegetables. Correlations between lipophilic plasma ORAC and FFQ-based ORAC, TRAP, and FRAP estimates from fruit and vegetables were 0.41, 0.31, and 0.28, and correlations with plasma TRAP estimates were 0.31, 0.30, and 0.28, respectively. Hydrophilic plasma ORAC and plasma FRAP values did not correlate with FFQ-based TAC estimates. Reproducibility, assessed by intraclass correlations, was 0.60, 0.61, and 0.61 for FFQ-based ORAC, TRAP, and FRAP estimates, respectively, from fruit and vegetables., Conclusions: FFQ-based TAC values represent valid and reproducible estimates that may be used in nutritional epidemiology to assess antioxidant intake from foods. Further studies in other populations to confirm these results are needed.

With the aim to expand the Italian total antioxidant capacity (TAC) database, the TAC values of 11 spices, 5 dried fruits, 7 sweets, 18 cereal products, 5 pulses, and 6 nuts were determined using three different assays and considering the contribution of bound antioxidant compounds in fiber-rich foods (i. e. cereals, legumes, and nuts). Among spices, saffron displayed the highest antioxidant capacity, whereas among dried fruits, prune exhibited the highest value. The TAC values of all the chocolates analyzed were far higher than the other sweet extracts measured. Among cereal products, whole meal buckwheat and wheat bran had the greatest TAC. Among pulses and nuts, broad bean, lentil and walnuts had the highest antioxidant capacity, whereas chickpeas, pine nuts and peanuts were less effective. The contribution of bound phytochemicals to the overall TAC was relevant in cereals as well as in nuts and pulses. The complete TAC database could be utilized to properly investigate the role of dietary antioxidants in disease prevention.

Cancer has a complex etiology with multiple risk factors that involve the interplay between genetic and environmental influences. There is compelling evidence that dietary plant foods appear to be protective against certain type of cancers. Among a number of mechanistic hypotheses, diet-derived antioxidants have been proposed to contribute to explain these findings. However, contrasting results from intervention trials have raised strong concerns about the influence of antioxidants on human health. A vulnerable point of the research on antioxidants is the lack of information on the effect of the whole array of dietary antioxidants in cancer prevention because so far mainly single molecules have been investigated. Total antioxidant capacity (TAC) considers the single antioxidant activity as well as the synergistic interactions of the redox molecules present in complex matrixes, giving an insight into the assessment of the non-enzymatic antioxidant network. This article will outline the state of art of the research on TAC and cancer, describing the plasma non-enzymatic antioxidant network and its association with diet. The feasibility of TAC assessment as an innovative tool for investigating the association between dietary antioxidants, oxidative stress, and cancer will be also discussed.

Inflammation, a risk factor for cardiovascular disease, is associated with low plasma levels of antioxidant vitamins. In addition to vitamins, other antioxidants modulate the synthesis of inflammatory markers in vitro and contribute to the total antioxidant capacity (TAC) of a diet. However, the relationship between dietary TAC and markers of inflammation has never been evaluated in vivo. We investigated the relationship between dietary TAC and markers of systemic (high-sensitivity C-reactive protein (hs-CRP), leucocytes) and vascular (soluble intercellular cell adhesion molecule-1) inflammation in 243 non-diabetic subjects. General Linear Model (GLM) analysis showed a significant (P=0.005) inverse relationship between hs-CRP and quartiles of energy-adjusted dietary TAC, even when recognized modulating factors of inflammation, namely alcohol, fibre, vitamin C, alpha-tocopherol, beta-carotene, BMI, waist circumference, HDL-cholesterol, hypertension, insulin sensitivity and plasma beta-carotene, were included in the model as covariates (P=0.004). The relationship was stronger for subjects with hypertension (P=0.013 v. P=0.109 for normotensive individuals). Among dietary factors, TAC was significantly higher (5.3 (sd 3.0) v. 4.9 (sd 2.7) mmol Trolox/d; P=0.026) in subjects with low plasma hs-CRP (range: 0.0-4.1 mg/l) than in subjects with high plasma hs-CRP (range: 4.2-27.8 mg/l). We conclude that dietary TAC is inversely and independently correlated with plasma concentrations of hs-CRP and this could be one of the mechanisms explaining the protective effects against CVD of antioxidant-rich foods such as fruits, whole cereals and red wine. This could be of particular significance for subjects with high blood pressure.

Convincing evidence suggests that blood redox changes play a role in the development of various cardiovascular disorders including hypertension. Nutritional antioxidants have been suggested to play a role in cardiovascular disease prevention. In this study, we investigated in vivo changes in rat arterial blood pressure induced by acute exposition to an increased load of peroxyl radicals and by the administration of selected antioxidants after chemically induced oxidative stress. Hydrosoluble and liposoluble peroxyl radicals, generated by 2,2'-azobis-(2-amidinopropane) dihydrochloride and 2,2'-azobis 2,4-di-methylvaleronitrile, induced a dose-dependent decrease in rat blood pressure. All antioxidants tested (6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid, vitamin C, glutathione and dithiothreitol) returned peroxyl radical-induced hypotension to normal. Of the various antioxidants tested, glutathione was the most effective in restoring blood pressure after peroxyl radical generation. Treatment of rats with a thiol-chelating agent (N-ethylmaleimide) and an oxidizing agent (5,5'-dithiobis-2-nitrobenzoic) inhibited peroxyl radical-mediated hypotension. Our results suggest that acute exposition to peroxyl radicals have a hypotensive effect on blood pressure and that thiols play an active role in the redox regulation of blood pressure. Other experiments are needed to clarify the role played by oxidative potentials on blood pressure and the mechanism of action of nutritional antioxidants.

Total Antioxidant Capacity (TAC) considers the cumulative action of all the antioxidants present in plasma and body fluids, thus providing an integrated parameter rather than the simple sum of measurable antioxidants. The capacity of known and unknown antioxidants and their synergistic interaction is, therefore, assessed, thus giving an insight into the delicate balance in vivo between oxidants and antioxidants. There is new evidence indicating the importance of understanding the mechanisms of the homeostatic control of TAC in plasma and tissues and its modification during oxidative stress development. Recently, the epidemiological application of TAC has been proposed as a new tool for investigating the relationship between dietary antioxidants and cancer risk in population studies. This review outlines the pros and cons of the more common assays for measuring plasma TAC and the latest findings on dietary modulation of plasma redox status. Finally, the feasibility of the 'TAC concept' as an innovative tool for investigating the association between diet and oxidative stress is discussed.

Epidemiologic studies have demonstrated an inverse association between consumption of fruits and vegetables and morbidity and mortality from degenerative diseases. The antioxidant content of fruits and vegetables may contribute to the protection they offer from disease. Because plant foods contain many different classes and types of antioxidants, knowledge of their total antioxidant capacity (TAC), which is the cumulative capacity of food components to scavenge free radicals, would be useful for epidemiologic purposes. To accomplish this, a variety of foods commonly consumed in Italy, including 34 vegetables, 30 fruits, 34 beverages and 6 vegetable oils, were analyzed using three different assays, i.e., Trolox equivalent antioxidant capacity (TEAC), total radical-trapping antioxidant parameter (TRAP) and ferric reducing-antioxidant power (FRAP). These assays, based on different chemical mechanisms, were selected to take into account the wide variety and range of action of antioxidant compounds present in actual foods. Among vegetables, spinach had the highest antioxidant capacity in the TEAC and FRAP assays followed by peppers, whereas asparagus had the greatest antioxidant capacity in the TRAP assay. Among fruits, the highest antioxidant activities were found in berries (i.e., blackberry, redcurrant and raspberry) regardless of the assay used. Among beverages, coffee had the greatest TAC, regardless of the method of preparation or analysis, followed by citrus juices, which exhibited the highest value among soft beverages. Finally, of the oils, soybean oil had the highest antioxidant capacity, followed by extra virgin olive oil, whereas peanut oil was less effective. Such data, coupled with an appropriate questionnaire to estimate antioxidant intake, will allow the investigation of the relation between dietary antioxidants and oxidative stress-induced diseases.