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This study aims to evaluate the effect of grape seed extract on the thermal oxidation of soybean oil.

Four treatments were used: soybean oil (SO), butylhydroxytoluene (BHT), antioxidant at concentration of 100 mg/kg in soybean oil (BHTSO), grape seed extract at a concentration of 100 mg/kg in soybean oil (Extract), and mixture at a concentration of 50 mg/kg of grape seed extract (Mixture) and 50 mg/kg of BHT in soybean oil subjected to 180°C for 20 h. The total phenolic compounds were quantified by spectrophotometry using the Folin-Ciocalteu reagent. The antioxidant activity was evaluated by the ABTS^•+, DPPH^• and FRAP acid systems. The fatty acid composition and phytosterols were determined by gas chromatography (GC) and tocopherols were determined by high-performance liquid chromatography.

Among the treatments studied, the Extract and the Mixture presented lower losses of total phenolic compounds, DPPH^• and FRAP, while BHTSO had an opposite effect. After 10 h of heating, the Mixture and the Extract were more effective in reducing the formation decomposition products, measured by the amount of total polar compounds. The Mixture resulted in higher retention of essential fatty acids at the end of heating. The Extract and Mixture showed higher retention rates of total tocopherols and the Mixture resulted in 338.71 mg/100 g (P ≤ 0.05) of total phytosterol after 20 h of heating.

Oils undergoing the heating process suffer major changes, requiring the addition of antioxidant compounds. As a result of the questioning on the use of chemical additives, research on natural antioxidants, as substitute to the synthetic ones, is increasing. Among the natural compounds with high antioxidant potential, the grape wastes such as its seeds are highlighted. Studies using grape seed extract are scarce.

The purpose of this paper is to evaluate the oxidative stability of soybean oil added by Lentinus edodes and Agaricus blezei extracts in accelerated storage test.

The following treatments were subjected to accelerated storage test in an oven at 60°C for 15 days: Control (soybean oil without antioxidants), TBHQ (soybean oil+100 mg/kg of TBHQ), BHT (soybean oil+100 mg/kg of BHT), L. edodes (soybean oil+3,500 mg/kg of L. edodes extract) and A. blazei (soybean oil+3,500 mg/kg of A. blazei extract). The samples were taken every three days and analyzed for peroxide values and conjugated dienes.

At the end of 15 days, the treatments TBHQ, A. blazei, L. edodes, Control and BHT showed 6.47, 8.81, 41.53, 71.28 and 78.40 meq/kg, respectively, for peroxide values and 0.37, 0.40, 0.67, 1.07 and 1.00 per cent, respectively, for conjugated dienes.

The research indicates that mushrooms may be a promising source of natural antioxidants. Therefore, natural extracts of mushrooms can be applied to vegetable oils as a way to reduce the degradation caused by lipid oxidation.

The purpose of this paper is to characterize oils extracted from Bertholletia excelsa, Lecythis pisonis, Dipteryx lacunifera, Carya illinoensis and Juglans regia, regarding their characterization and fatty acid profile.

The oils were extracted from oilseeds by cold pressing and physico‐chemical characterization was performed by using standard methods for oils and fats. The oxidative stability and fatty acid profile also were determined.

According to the results, the physico‐chemical properties of oils from nuts and walnuts were comparable to those of good quality conventional oils. The oil seeds are a good source of unsaturated fatty acids, especially oleic and linoleic acids.

Implies the identification of fatty acid profile and physico‐chemical properties of oils extracted from nuts and walnuts, and to prevent certain types of diseases.

The paper identifies a new source of essential fatty acids extracted from oilseeds.

The purpose of this paper is to characterize lychee seeds regarding their centesimal composition, and also to evaluate their antioxidant potential and fatty acid profile.

To obtain the extract, dehydrated and grinded seeds were extracted with ethyl alcohol for 30 min, at a proportion of 1:3 of seeds:ethyl alcohol, under continuous agitation, at room temperature. Afterwards, the mixture was filtered and the supernatant subjected to a rotoevaporator at 40^oC aiming to determine, by direct weighing, the extract dry matter yield.

The largest found values went to the total carbohydrates (72.75 percent). In the oil from the lychee seeds there was a high percentage of unsaturated fatty acids, the main component being linoleic, considered an essential fatty acid.

Implies the identification of compounds biativos extracted from seeds of tropical and subtropical fruits, and to prevent certain types of diseases.

The article tries to identify new source of phenolic compounds extracted from fruit.

This research aims to evaluate the antioxidant potential of oregano extract (OE), as well as its isolated and synergistic effect when applied to soybean oil (SO) under thermal oxidation.

In order to determine the antioxidant activity of oregano extract and its synergistic effect with tert‐butylhydroquinone (TBHQ), thermal oxidation was performed using the following treatments: SO, SO with 50 mg/kg of TBHQ, SO with 3,000 mg/kg of OE, and SO with 3,000 mg/kg of oregano extract and 50 mg/kg of TBHQ (mixture). The treatments underwent heating at 180°C for 20 hours, and analyses of oxidative stability, total polar compounds, tocopherols and fatty acids composition were performed. The results obtained were subjected to analysis of variance and Tukey test for averages at 5 percent, using the program ESTAT version 2.0.

Considering the results of antioxidant activity and total phenolic compounds, it was possible to verify that the ethanolic extract of oregano has presented antioxidant potential. Furthermore, considering the results obtained in the analyses of oxidative stability, polar compounds, tocopherols and fatty acids profile, it was possible to observe that the extract has prevented lipid oxidation when added to SO.

The study offers information on the use of natural antioxidants as an alternative to the use of synthetic antioxidants, which can be considered toxic.

This study aims to analyze the soursop and sugar apple seeds as to its composition, to evaluate the antioxidant potential of seeds extract and characterize the oil extracted from them, regarding the fatty acids profile and content of tocopherols.

To obtain the extracts, dried and crushed seeds were extracted with ethanol for 30 minutes, at a ratio of 1:3 (m/m, seed: ethyl alcohol) under continuous stirring at room temperature. Then, the mixture was filtered and the supernatants subjected to rotoevaporator at 40°C aiming to determine, by direct weighing, the yields of dry extracts.

According to the results, the soursop and sugar apple seeds constituted significant sources of lipids, proteins and carbohydrates and can therefore be used in food and feed, and offer relevant antioxidant activity of phenolic compounds. The oil seeds are a good source of unsaturated fatty acids, especially oleic and linoleic acids and they have significant amounts of total tocopherol.

Implications are the identification of bioactive compounds extracted from seeds of tropical and subtropical fruits, and to prevent certain types of diseases.

The information presented might be directly used for developing of functional foods such as fruits.

The article tries to identify new source of compounds extracted from fruits.

This study aims to deal with the evaluation of the antioxidant capacity of lyophilized hydroalcoholic extracts of red peppers in natura. Furthermore, preference was evaluated for the taste and color of soybean oil added red pepper extracts.

The antioxidant capacity was determined by four methods. The content of phenolic compounds, carotenoids and ascorbic acid in the extracts was determined by chromatographic, spectrophotometric and titration methods, respectively.

The results showed that the highest antioxidant capacity was found in Malagueta pepper extract through reducing power (FRAP) method. In this same extract, high amount of phenolic compounds was found. However, the extracts of Bode and Dedo-de-moça peppers had higher amounts of carotenoids and ascorbic acid, respectively. Sensorially, the oil added extracts were preferred.

Red peppers are very popular and consumed worldwide, besides being constituted of important phytochemicals. Results showed high antioxidant activity in the extracts of peppers, and high content of phenolic compounds, carotenoids and ascorbic acid mainly in chili. This study highlights the importance of the extracts of red peppers, genus Capsicum, as a source of antioxidants, in addition to vegetable oils.

It is important to check the acceptance of the application of extract in vegetable oil, so it can be marketed as a natural antioxidant. This study provides valuable information about the antioxidant capacity of extracts of red peppers and its acceptance.

This paper aims to characterize the pumpkin (Cucurbita sp) seed oil from the varieties Nova Caravela, Mini Paulista, Menina Brasileira (Cucurbita moschata) and Moranga de Mesa (Cucurbita maxima) as to their physicochemical properties, vitamins and fatty acid and triacylglycerols profiles.

The oils were extracted from oilseeds by the Bligh and Dyer (1959) method, and chemical characterization was performed by using standard methods for oils and fats. The vitamin A and E content, fatty acid profile and triacylglycerols profile also were determined.

About the chemical properties, the oils showed values within the range for edible vegetable oils. The oil from variety Nova Caravela stood out for presenting better quality, as it showed lower values of free fatty acids, acidity and peroxides. However, it was found that the Moranga de Mesa oil was the most unsaturated, due to the high refractive and iodine index, and was also reported to have lower oxidative stability. Among the unsaturated fatty acids, ranging from 70 to 78 per cent of the total obtained, linoleic and oleic acids stood out, while among the saturated ones, palmitic and stearic did.

These seeds are rich in high-quality lipids; therefore, their use could help to reduce the amount of waste produced in the industries, and consequently reduce environmental contamination. This study showed that the seeds could be used as a raw material for oil extraction, and also could be used for developing functional foods instead of being discarded.

This study provides valuable information about the quality and fatty acid contents of pumpkin seed oils consumed in Brazil.

The objective of this study was to evaluate the antioxidant effect of oregano and thyme extracts isolatedly and combinedly applied in soybean oil.

Soybean oil containing 3,000 mg/kg of oregano and thyme oleoresins and the mixture of both, as well as soybean oil containing TBHQ (50 mg/kg) and soybean oil free of antioxidants, were subjected to accelerated oven test (60°C/10 days). Samples were collected every two days and analyzed as to their peroxide and conjugated diene values.

The mixture of oleoresins and consequent increase of concentration were as effective as the antioxidant TBHQ.

These studies may prove to be beneficial to the exploitation of natural antioxidant sources for the preservation and/or extension of raw and processed food shelf life. Therefore, they could also be applied in the area of pharmaceuticals for the protection of human life.

This study offers information on the use of natural antioxidants as an alternative to the use of synthetic antioxidants, which might be considered toxic.

The purpose of this paper is to evaluate the antioxidant activity of ginger ethanol extract in soybean oil under thermoxidation.

A total of four treatments were used: soybean oil free of synthetic antioxidants, soybean oil containing 2,500 mg/kg of ginger extract, soybean oil containing 50 mg/kg of TBHQ, soybean oil containing the mixture of natural extract, and TBHQ in the before‐cited concentration. The treatments were discontinuously submitted to plates heated at 180°C, for 20 hours. Samples were removed in the times of 0, 4, 8, 12, 16 and 20 hours of heating and they were analyzed as to their oxidative stability, total polar compounds, peroxide and conjugated diene values.

The results showed the efficiency of the ginger extract in protecting the oil against lipid oxidation. It could be concluded that ginger extract might be indicated as an additive that acts against lipid oxidation and, consequently, increases shelf life of food.

These studies may prove to be beneficial to the exploitation of natural antioxidant sources for the preservation and/or extension of raw and processed food shelf life. Therefore, they could also be applied in the area of pharmaceuticals for the protection of human life.

This study offers information on the use of natural antioxidants as an alternative to the use of synthetic antioxidants, which might be considered toxic.