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The purpose of this review is to summarize new research indicating that high-dose supplements of the antioxidant vitamin C can interfere with the benefits of physical exercise for athletic performance and the risk for chronic disease.

This article reviews current original literature on the regulation of human metabolism by oxidants and antioxidants and evaluates the role of exercise and high-dose vitamin C in this context. The presentation in this article aims to be informative and accessible to both experts and non-experts.

The evidence reviewed here indicates that single, high-dose supplements of the antioxidant vitamin C abolish the beneficial effects of athletic training on muscle recovery and strength as well as abolishing the benefits of exercise in lowering the risk for chronic disease. In contrast, an antioxidant-rich diet based on regular foods apparently enhances the benefits of exercise. These findings are consistent with an updated understanding of the critical importance of both oxidants and antioxidants in the regulation of human metabolism. While more research is needed to address the role of timing and level of antioxidant consumption, it is clear that a balance between oxidants and antioxidants is essential.

The information presented in this review is important for both athletes and the public at large in their efforts to choose nutrition and exercise regimes appropriate to maximize the outcome of their training efforts and lower their risk for chronic disease.

This article provides accessible and comprehensive information to researchers, nutritionists, and consumers interested in optimal nutrition during athletic training and for obtaining the full benefit of physical exercise in lowering the risk for chronic disease.

The purpose of this paper is to determine the antioxidant properties (capacity and component) of four non‐leafy vegetables. The correlation between the antioxidant capacity and its components of the studied vegetables was also assessed.

Winged beans, also known as four‐angled bean (Psophocarpus tetragonolobus), French bean (Phaseolus vulgaris), string bean (Vigna sinensis) and snow pea (Pisum sativum) were selected as samples from among the common non‐leafy vegetables consumed by Malaysians. These fresh vegetables were lyophilised and ground and their ethanolic extracts were prepared for antioxidant capacity assays and total phenolic, β‐carotene and ascorbic acid contents.

Among the vegetables, string beans showed the highest antioxidant capacity compared to the other vegetables studied (p < 0.05). The total phenolic, ascorbic acid and β‐carotene contents of snow peas were significantly higher (p < 0.05) than the other vegetables. There was a significant positive correlation between scavenging activity and antioxidant components studied. On the other hand, a negative correlation was found between antioxidant activity and its components of the studied vegetables.

Previous reports have indicated that vegetables contain high levels of antioxidants. However, data on antioxidant capacity of these non‐leafy vegetables are still lacking. This research paper shows the non‐leafy vegetables studied is a promising source of antioxidants with good antioxidant capacity. Beside that, along with the studied antioxidant components, other compounds in these vegetables could also contribute to their antioxidant capacity.

Examines the antioxidant activities of a range of hydroxy‐substituted phenolic acids by estimating their relative abilities to scavenge the ABTS_+ radical cation generated in the aqueous phase, expressed as the Trolox equivalent antioxidant capacity (TEAC value). These common food components have varying reducing abilities, dependent on the positions and extent of hydroxylation of their phenol ring. Reports the research results which suggest that some simple phenolic acids are most effective antioxidants, up to two to three times as active as vitamin C. Their relative abundance in fruits, oils, etc. indicates that they may be highly significant contributors to the overall dietary antioxidant intake. Para‐coumaric acid (4‐hydroxycinnamic acid) was found to have a TEAC value of 2.2mM (more than twice the antioxidant activity of vitamin C). Ferulic acid (3‐methoxy, 4‐hydroxycinnamic acid), the active component of oryzanol (rice bran oil) was found to have a TEAC value of 1.9 mM and gallic acid (3, 4, 5‐trihydroxybenzoic acid) a TEAC of 3.0mM (i.e. three times the antioxidant activity of vitamin C). Discusses the significance of these and other related compounds as food antioxidants and as non‐nutrient antioxidants in the diet.

The purpose of the study was to develop a powder shampoo with antioxidant attributes.

Dry shampoo compositions were formulated containing alpha olefin sulfonate (AOS), sodium cocoyl isethionate (SCI), microcrystalline cellulose, mannitol, carboxymethyl cellulose, maltodextrin and sodium benzoate with or without extract of Cinnamomum zeylanicum bark. Cinnamon extract was chosen for this study owing to its ubiquitously known antioxidant attributes. The formulations were tested for detergency action and antioxidant potential in vitro.

Cinnamomum zeylanicum extract exhibited noticeable antioxidant activity in vitro. The authors observed that addition of the bark extract to the shampoo formulation was associated with remarkable increase in total phenolic content, total antioxidant activity and radical scavenging activity without any effect on detergency action.

This preliminary study provides a powder shampoo formulation which exhibits antioxidant attributes as a result of incorporation of cinnamon bark extract. Clinical efficacy of the formulation remains to be tested.

Owing to the powder format of the shampoo, the formulation can be manufactured with ease and economically. Functionalizing the formulation with enhancement of antioxidant activity by incorporation of cinnamon bark extract may be associated with beneficial clinical outcomes, which remains to be tested.

The proposed formulation may be stored and sold in eco-friendly packing material, thus could pave the way for reducing the burden of plastic consumption by the shampoo industry.

The present work demonstrates that incorporation of cinnamon bark extract to a powder shampoo formulation, containing AOS and SCI as principle surfactants, significantly enhances its antioxidant attributes.

The aim of this paper is to study the effects of commercially available antioxidants on the oxidation stability of white mineral oils (paraffin oil).

Twelve commercially available antioxidants (Chimassorb 81, Tinuvin 326, Tinuvin 765, Tinuvin 571, Irganox L57, Irganox L109, Irganox L101, Irganox L115, Irganox L06, Irgafos 168, Naugard 445, BHT) were added to pharmaceutical and technical grade white mineral oils at 0.1%, 0.2%, 0.3%, 0.6% and 0.8% (w/w) concentrations. Light, heat and oxygen were applied to induce and accelerate oxidation. Total acid number, viscosity and 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity of the oils were measured to evaluate the performance of the antioxidant additives.

Results showed that combined heat and oxygen treatment was the most effective of the three conditions tested to cause oxidation. Based on the data, the best antioxidant additives to be used in white oils are decided to be Irganox L06 and Irganox L101. It was also found that the grade of oils (technical or pharma) did not create a significant difference in the results obtained.

To the best of the authors’ knowledge, this is the first study that reports effects of antioxidant addition on the oxidative properties of white mineral oils. This study advances knowledge of the behavior of white mineral oils under real atmosphere and provides comprehensive data on how the antioxidants affect the light, thermal, oxidative degradation of white mineral oils. The data presented also provide an insight to extend life expectancy of white mineral oils.

The study aims to describe the main classes of antioxidants existing in fruit, beverages, vegetables and herbs and the different extraction and application of antioxidants in food. Oxidative degradation of lipids, especially induced by reactive oxygen species, leads to quality deterioration of foods and cosmetics and could have harmful effects on health. A major challenge is to develop tools to assess the antioxidant capacity and real efficacy of these molecules. Recently, many review papers regarding antioxidants from different sources and different extraction and quantification procedures have been published. However, none of them has all the information regarding antioxidants (sources, extraction and application in food).

This paper tries to take a different perspective on antioxidants for the new researcher involved in this field.

Antioxidants from fruit, vegetables and beverages play an important role in human health, for example, preventing cancer and cardiovascular diseases and lowering the incidence of different diseases. A number of plant products act as scavengers of free radical species and so have been classified as antioxidants. Antioxidants are an important group of food additives that have the ability to protect against detrimental change of oxidizable nutrients and consequently they extend shelf-life of foods.

Most of the antioxidants present in foods are phenolic and polyphenolic compounds, but their efficacy in food for the prevention of oxidation or in the body for dealing with oxidative stress and its consequences depends on different factors.

This study collected the last finding in the field of sources and applications of natural antioxidants.

The purpose of this paper is to study the efficiency of lignin/silica and calcium lignate/calcium silicate as natural antioxidants in styrene-butadiene rubber (SBR) vulcanizates.

It has been found that thermal aging data of the aged sample revealed that SBR vulcanizate undergoes crosslink reactions that lead to embrittlement and ultimately failure. Incorporation of lignin/silica or calcium lignate/calcium silicate, however, resulted in significant improvement of the degradation profile of the vulcanizates at 90±1°C. Loss of tensile strength and flexibility during aging of the SBR compounds with 8 phr lignin/silica or calcium lignate/calcium silicate was mild relative to unfilled polymer, indicating a restricted degradation due to the presence of the investigated compounds. The results obtained revealed that the investigated compounds are good antioxidant, and the evaluation was confirmed by physico-mechanical properties of the vulcanizates, FT-IR spectroscopy, transmission (TEM) and scanning (SEM) electron microscope.

It was noticed that SBR vulcanizates having 8 phr of lignin/silica or calcium lignate/calcium silicate exhibited the best mechanical properties in comparison with other concentrations (1, 2, 4, 6 and 10 phr). Also, results revealed that the lignin/silica derivatives are efficient antioxidants in SBR vulcanizates compared to vulcanizates containing conventional antioxidants used in rubber industry, namely polymerized 2,2,4-trimethyl-1, 2-dihydroquinoline (TMQ), and N-isopropyl-N'-phenyl-P-phenylenediamine (IPPD).

All these results indicated that lignin/silica and calcium lignate/calcium silicate in SBR had good heat resistance and aging resistance, calcium lignate/calcium silicate has an application limitation as not all vulcanizates need to use CaCO₃/calcium salts.

Lignin is usually seen as a waste product of pulp and paper industry and is often used as fuel for the energy balance of the pulping process. It is simple isolation along with silica from rice straw and using it as an antioxidant added further practical utility for this waste.

The importance of lignin/silica derivatives is arisen from their biodegradability and their ease availability from rice straw black liquor.

The purpose of this study is to reduce the use of Zinc dialkyl dithiophosphates (ZDDP) and improve the frictional properties and thermal oxidation stability of Perfluoropolyether (PFPE) grease by adding antioxidant additives. The addition of antioxidants can reduce the consumption of ZDDP as an antioxidant, thus improving the anti-wear efficiency of ZDDP and reducing the excess phosphorus element in the grease.

In this study, an antioxidant with good comprehensive performance was selected from several antioxidants by tribological tests and high-temperature tests. Then, the effect of its combination additive with ZDDP on PFPE grease was investigated. The anti-wear property, anti-friction property, thermal oxidation stability and extreme pressure property of greases containing different proportions of ZDDP and antioxidant were tested by four-ball tester and synchronous thermal analyzer (STA). The effects of additives on properties of grease were analyzed by SEM, EDS, LSCM, XPS and FT-IR.

The research shows that 2,6-Di-tert-butyl-4-methylphenol (BHT) can be used as an antioxidant in combined additives to reduce the antioxidant reactions of ZDDP, thus improving the anti-wear efficiency of ZDDP and further enhancing the anti-wear performance of the grease. Moreover, BHT and ZDDP have a synergistic effect on the high temperature performance of the PFPE grease due to their different antioxidant mechanisms.

In this paper, the problems related to PFPE grease are studied, which has a certain guiding effect on the industrial application of fluorine grease and the related formulation design.

In this paper, the properties of PFPE grease under different lubricating condition were studied. The synergistic lubrication effect of antioxidant and ZDDP are discussed. It provides experimental and theoretical support for reducing the content of ZDDP and improving the performance of additives.

Salak (Salacca zalacca) is an underutilised fruit. The bioactivities of this fruit have rarely been studied scientifically. Thus, the present study aimed to determine the antioxidant activity of extracts derived from the peel, fruit and kernel of the Salak fruit, as well as the hypoglycemic and anti-hypertensive properties of Salak peel extracts.

The peel, fruit and kernel of the Salak were extracted using distilled water, methanol and ethanol. Antioxidant activities, angiotensin-converting enzyme (ACE) and alpha-amylase inhibition properties of the extracts were estimated via in vitro standard methods. Besides, the total phenolic content (TPC) and total flavonoid content (TFC) of the extracts were also determined in the present study. The antioxidant activities of different parts of Salak extracts were determined by ferric-reducing antioxidant power (FRAP) and Trolox equivalent antioxidant capacity (TEAC) methods. Percent of radical scavenging properties were calculated via DPPH assay. The hypoglycemic and anti-hypertensive properties of Salak peel were evaluated using alpha-amylase inhibition and ACE assays, respectively.

Fruit extracts of Salak in methanol were found to exhibit the highest TPC (10.27 ± 0.12 mg GAE/g), TFC (11.04 ± 0.89 mg CE/g) and antioxidant properties amongst all samples whereby the TPC and TFC were strongly correlated with antioxidant activities. On the other hand, distilled water extracted Salak kernel showed to have the lowest TPC (0.53 ± 0.05 mg GAE/g), TFC (0.37 ± 0.01 mg CE/g) and antioxidant properties amongst all the Salak extracts. Peel extracts exhibit comparable antioxidant activities with fruit extracts in the current findings. In addition, peel extracts indicated some extend of ACE and alpha-amylase inhibition activities regardless of the solvents used. Methanol and ethanol peel extracts indicated no significant difference (p < 0.05) ACE (98%) and alpha-amylase (90%) inhibition activities. However, distilled water extracted Salak peel showed significantly lower ACE and alpha-amylase inhibition in comparison to methanol and ethanol peel extracts.

The present findings suggested that the fruit of Salak exhibits the highest antioxidant properties, followed by the peel and lastly, the kernel, which shows the lowest antioxidant properties amongst all the samples. The results also indicated that the peel extracts have ACE and alpha-amylase inhibition activities.

This study aims to analyze the antioxidant properties of the Mediterranean diet and describe methods that are used in clinical studies to assess its role in reducing oxidative stress.

The review presents the results of interventional and observational clinical trials aimed at assessing the influence of the Mediterranean diet on the level of enzymatic and non-enzymatic antioxidants, as well as the total blood antioxidant capacity.

The Mediterranean diet as a varied diet can be a better way to provide antioxidants to the body than supplements. Individual compounds administered in an isolated form can give the opposite effect to the expected, stimulating oxidative stress. The administration of antioxidants in the form of supplements instead of a varied diet is also associated with a lack of synergism of action. In studies on the importance of the Mediterranean diet in the reduction of oxidative stress, single markers are used to measure oxidative damage, the activity of enzymatic antioxidants and the concentration of individual non-enzymatic antioxidants. At the same time, the need to find markers that would assess the level of oxidative stress and the body’s antioxidant capacity more comprehensively is emphasized.

It should be taken into account that differences between in vivo and in vitro results may result from the fact of various factors, including genetic, smoking, intestinal microflora or diet composition. It is also necessary to answer the question about which marker or set of markers could in the most comprehensive way to assess the level of oxidative stress and the body’s antioxidant capacity.

The literature review shows not only the source of antioxidants in the Mediterranean diet. This paper also presents a critical approach to markers that allow the assessment of the antioxidant properties of the diet.