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Nonalcoholic steatohepatitis (NASH) is considered growing risk factor for hepatocellular carcinoma development in high-income countries. Diet- and chemically induced rodent models have been applied for the translational study of NASH-associated hepatocarcinogenesis due to their morphological and molecular similarities to the corresponding human disease. Arctium lappa L. (burdock) root tea has been extensively consumed in Traditional Chinese Medicine due to its potential therapeutic properties. Indeed, the bioactive compounds of A. lappa root, as the polyphenols, have already showed antioxidant and anti-inflammatory properties in different in vivo and in vitro bioassays. In this study, we investigated whether burdock root ethanolic extract (BRE) administration attenuates NASH-associated hepatocarcinogenesis. Eight-week-old male Wistar rats received choline-deficient high-fat diet for 8 weeks and multiple thioacetamide doses for 4 weeks in order to induce NASH and preneoplastic glutathione-S-transferase pi (GST-P) + preneoplastic foci. Subsequently, rats were treated with BRE (100 or 200 mg/kg body weight) or vehicle by oral gavage for 2 weeks. BRE displayed high levels of chlorogenic and caffeic acids and BRE administration reduced total fatty acid and lipid hydroperoxide levels, while increasing the activities of antioxidant superoxide dismutase and catalase enzymes in the liver. Furthermore, burdock intervention diminished the size of GST-P + remodeling preneoplastic lesions (PNLs) and displayed a trend on reducing hepatocyte proliferation (Ki-67) inside them. These findings suggest that short-term exposure to BRE alleviated remodeling PNL development in NASH-associated hepatocarcinogenesis., (© 2019 Wiley Periodicals, Inc.)

The objective of this study was to correlate the free radical scavenging and antioxidant activity of two known substances (Trolox and alpha-tocopherol), using three in vitro methods (linoleic acid emulsion, brain homogenate and 2,2-diphenyl-1-picryl-hydrazyl [DPPH]). At steady state, alpha-tocopherol showed a greater inhibition of spontaneous oxidation of brain homogenate (59.42%+/-1.91) than Trolox (38.50%+/-2.38), while the latter showed a better antioxidant activity performance regarding inhibition of linoleic acid peroxidation (100% versus 84.02%+/-1.98) and free radical scavenging activity (93.56%+/-5.71 versus 66.72%+/-6.28). When the IC50 value was used as a parameter, alpha-tocopherol presented greater antioxidant activity than Trolox evaluated in brain homogenate and DPPH, without a significant difference when using linoleic acid emulsion. Both compounds showed the same antioxidant efficiency measured by DPPH kinetics (0.37 mM). Antioxidant activity significantly changed according to the substrate, the parameter adopted to compare the substances in the same method and the form used to express antioxidant concentration.

Echium seed oil is an alternative source of omega 3 fatty acids but it is highly susceptible to oxidation. A combination of three natural strategies was proposed in this study aiming to improve the oxidative stability of echium oil obtained by pressing (PO) or solvent extraction (PSO), kept in the storage condition for 180 days or during the consumption for 30 days. Our results showed that the reduction of temperature was sufficient to keep the oil stable during storage for both samples. During the consumption time, the best stability was achieved by adding a mixture of antioxidants, composed of sinapic (500 ppm), ascorbic (250 ppm), and citric (150 ppm) acids, and/or 20% of high oleic sunflower oil. The combined strategies promoted a 34 to 80% reduction of peroxide value and 0 to 85% reduction of malondialdehyde concentrations in the samples, showing to be a feasible and natural alternative to improve the oxidative stability of echium oil. Practical Application: Our study successfully applied an optimized combination of simple and low‐cost strategies to enhance the chemical stability of echium seed oil. As the use of echium oil expands around the world, the oil industry and final consumers may benefit from our results to increase the oil shelf‐life. [ABSTRACT FROM AUTHOR]

The objective of this study was to apply the statistical technique known as response surface methodology (RSM) to model the free radical scavenging activity of mixtures of three antioxidant compounds, using 2,2-diphenyl-1-picrylhydrazyl (DPPH•). α-Tocopherol showed the highest antioxidant power (EC50) while ascorbic acid showed maximum antiradical efficiency. Reduced glutathione was not effective using the DPPH• system. The binary and ternary mixture effects were evaluated considering percentage reduction in [DPPH•] and the time needed to reach this reduction caused by addition of each mixture at 1.0 mm concentration. Although the surface curves have shown significant interactions, no combination between the compounds resulted in a greater percentage reduction in [DPPH•]/min than that shown by ascorbic acid alone. Both polynomial regressions were statistically significant with elevated adjusted R2. This study showed that RSM can be applied to predict the free radical scavenging activity of mixtures of antioxidants using the stable DPPH• as a free radical. [ABSTRACT FROM AUTHOR]

The objective of this study was to correlate the free radical scavenging and antioxidant activity of two known substances (Trolox and α-tocopherol), using three in vitro methods (linoleic acid emulsion, brain homogenate and 2,2-diphenyl-1-picryl-hydrazyl [DPPH]). At steady state, α-tocopherol showed a greater inhibition of spontaneous oxidation of brain homogenate (59.42%±1.91) than Trolox (38.50%±2.38), while the latter showed a better antioxidant activity performance regarding inhibition of linoleic acid peroxidation (100% versus 84.02%±1.98) and free radical scavenging activity (93.56%±5.71 versus 66.72%±6.28). When the IC 50 value was used as a parameter, α-tocopherol presented greater antioxidant activity than Trolox evaluated in brain homogenate and DPPH, without a significant difference when using linoleic acid emulsion. Both compounds showed the same antioxidant efficiency measured by DPPH kinetics (0.37 mM). Antioxidant activity significantly changed according to the substrate, the parameter adopted to compare the substances in the same method and the form used to express antioxidant concentration. [ABSTRACT FROM AUTHOR]

Oxidation of bulk oils involves radical molecules, transitions metals, and association colloids, among other factors. Combining mechanistically different antioxidants is one possible strategy to improve oxidative stability of polyunsaturated fatty acids rich oils. However, antioxidant polarity may play a critical role in the oxidative protection efficacy. Thus, the objective of this study is to formulate a hydrophilic mixture (HM) containing sinapic, ascorbic, and citric acid; and a lipophilic mixture (LM) composed of α‐tocopherol, ascorbyl palmitate, and citric acid; and apply these mixtures in crude, and stripped flaxseed oils. The oxidative stability of crude oil samples containing HM and LM is comparable to that of artificial compounds mixture (ethylenediamine tetraacetic acid [EDTA] and terc‐butyl hydroquinone [TBHQ]). HM is more effective than LM in crude oil, but not in stripped oil, suggesting a strong influence of minor components on antioxidant activity of natural compounds. Practical Applications: The increasing demand for foods containing polyunsaturated fatty acids (PUFA) brings the challenge of their chemical stabilization. Here, a strategic mixture of hydrophilic natural antioxidants is effective to stabilize flaxseed oil, with effectiveness comparable to that of artificial antioxidants. Therefore, this HM constitutes a feasible and efficient option to be applied by food producers, especially in formulations that present a health claim. [ABSTRACT FROM AUTHOR]

Abstract: In this study, 73 South American red wines (Vitis vinifera) from 5 varietals were classified based on sensory quality, retail price and antioxidant activity and characterised in relation to their phenolic composition. ORAC and DPPH assays were assessed to determine the antioxidant activity, and sensory analysis was conducted by seven professional tasters using the Wine & Spirits Education Trust’s structured scales. The use of multivariate statistical techniques allowed the identification of wines with the best combination of sensory characteristics, price and antioxidant activity. The most favourable varieties were Malbec, Cabernet Sauvignon, and Syrah produced in Chile and Argentina. Conversely, Pinot Noir wines displayed the lowest sensory characteristics and antioxidant activity. These results suggest that the volatile compounds may be the main substances responsible for differentiating red wines on the basis of sensory evaluation. [Copyright &y& Elsevier]

The effect of eleven compounds extracted from red propolis on the oxidative stability of a functional emulsion was evaluated. Emulsions prepared with Echium oil as omega 3 (ω-3 FA) source, containing 1.63 g/100 mL of α-linolenic acid (ALA), 0.73 g/100 mL of stearidonic acid (SDA) and 0.65 g/100 mL of plant sterol esters (PSE) were prepared without or with phenolic compounds (vanillic acid, caffeic acid, trans -cinnamic acid, 2,4-dihydroxycinnamic acid, p -coumaric acid, quercetin, trans -ferulic acid, trans , trans -farnesol, rutin, gallic acid or sinapic acid). tert -Butylhydroquinone and a mixture containing ascorbic acid and FeSO 4 were applied as negative and positive controls of the oxidation. Hydroperoxide, thiobarbituric acid reactive substances (TBARS), malondialdehyde and phytosterol oxidation products (POPs) were evaluated as oxidative markers. Based on hydroperoxide and TBARS analysis, sinapic acid and rutin (200 ppm) showed the same antioxidant activity than TBHQ, representing a potential alternative as natural antioxidant to be applied in a functional emulsion containing ω-3 FA and PSE. [ABSTRACT FROM AUTHOR]

Abstract: It is not known if there is a correlation between in vitro and in vivo antioxidant activity of wines. Thus, in the present study, rats were fed with a high-fat diet to induce inflammation and oxidative stress, and received supplementation (1.0mL/day) containing water or three red wine samples characterised by high (41.1mmol TE/L), medium (35.7mmol TE/L) and low (14.4mmol TE/L) in vitro antioxidant activity. A correlation was observed between in vitro antioxidant activity measured in the wines and in vivo antioxidant activity measured in plasma (r =+0.49, p =0.011). In liver, only the wine containing the highest in vitro antioxidant activity was able to reduce malondialdehyde concentration. Groups supplemented with wines containing lower in vitro antioxidant activity showed an increase in antioxidant enzyme activity. We concluded that the correlation between in vitro and in vivo antioxidant activity depends on the biomarker selected to evaluate the oxidative stress. [Copyright &y& Elsevier]

Abstract: Introduction: Although the combination of statins with n-3 fatty acids seems to be beneficial under the lipid profile aspect, there is little information about the interaction of these two compounds on oxidative stress. Objective: Evaluate the interaction between statins and n-3 fatty acids on oxidative stress in women, using a 22 factorial design. Methods: Forty-three women participated in this crossover design. They were separated into two groups in which 20 were under statin treatment for more than 6 months, and 23 were normolipidemic. Within each group, half of the patients received capsules containing 2.4g/day of a mixture of EPA and DHA for 6 weeks, while the other half received a mixture of soya and corn oil. After a period of 90 days of washout, the groups were switched, and received the supplementation for 6 weeks more. Results: Statins reduced serum LDL and increased SOD expression. n-3 fatty acids increased the plasma malondialdehyde and SOD activity but reduced catalase expression (p <0.05). The interaction involving statins and n-3 fatty acids was nearly significant to the serum triacylglycerol reduction (p =0.054). Conclusion: Combining statins and n-3 fatty acids is an excellent strategy to reduce plasma cholesterol and triacylglycerol concentration in women. However, n-3 fatty acids increased the oxidative stress and the pleiotropic effect of statins seemed to be not enough to counterbalance this result. Our data also suggested that the mechanism by which n-3 fatty acids interfere in oxidative stress can be associated with antioxidant enzymes expression and activity. [Copyright &y& Elsevier]

The effect of the presence of surfactant micelles and of the mode of incorporation (pre-homogenization or post-homogenization) on the antioxidant efficiency of a homologous series of n-alkyl gallates phenolipids (G0, G3, G8, G12 or G16) was investigated in oil-in-water nanoemulsions. In both absence and presence of surfactant micelles, G12 and G16 were the best antioxidants. The effect of the mode of incorporation was modulated by the presence of surfactant micelles. In absence of surfactant micelles, G8 and G16 had higher efficiency when incorporated pre-homogenization, suggesting that the mode of incorporation promoted a distinct initial distribution of these compounds. In contrast, in presence of surfactant micelles, the antioxidants could be incorporated in any phases without efficiency loss. These results demonstrate the important role of surfactant micelles in modulating the antioxidant efficiency and could be used by the food industry to optimize emulsion formulations. • Alkyl gallates varying in chain lengths were investigated for their antioxidant efficiency in oil-in-water emulsion. • The mode of incorporation influences their activity to protect lipids from oxidation. • Interactions between antioxidant and emulsifier micelles modify antioxidants behavior. • Effect of the mode of incorporation was less important in the presence of surfactant micelles. [ABSTRACT FROM AUTHOR]