997 resultados para itaconic acid


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Fractionation of the EtOH extract from aerial parts of Baccharis uncinella C. DC. (Asteraceae) led to isolation of caffeic and ferulic acids, which were identified from spectroscopic and spectrometric evidence. These compounds exhibit antioxidant and anti-inflammatory properties and have been shown to be effective in the prevention/treatment of metabolic syndrome. This study investigated whether the combined treatment of caffeic and ferulic acids exhibits a more significant beneficial effect in a mouse model with metabolic syndrome. The combination treatment with caffeic and ferulic acids was tested for 60 days in C57 mice kept on a high-fat (40%) diet. The data obtained indicated that treatment with caffeic and ferulic acids prevented gain in body weight induced by the high-fat diet and improved hyperglycemia, hypercholesterolemia and hypertriglyceridemia. The expression of a number of metabolically relevant genes was affected in the liver of these animals, showing that caffeic and ferulic acid treatment results in increased cholesterol uptake and reduced hepatic triglyceride synthesis in the liver, which is a likely explanation for the prevention of hepatic steatosis. In conclusion, the combined treatment of caffeic and ferulic acids displayed major positive effects towards prevention of multiple aspects of the metabolic syndrome and liver steatosis in an obese mouse model.

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Organic acids are present in sour cassava starch ("polvilho azedo") and contribute with organoleptic and physical characteristics like aroma, flavor and the exclusive baking property, that differentiate this product from the native cassava starch. Samples of commercial sour cassava starch collected in South and Southeast Brazil were prepared for high performance liquid chromatography (HPLC) analysis. The HPLC equipment had a Biorad Aminex HPX-87H column for organic acid analysis and a refractometric detector. Analysis was carried out with 0.005M sulfuric acid as mobile phase, 0.6ml/min flow rate and column temperature of 60° C. The acids quantified were lactic (0.036 to 0.813 g/100g), acetic (0 to 0.068 g/100g), propionic (0 to 0.013 g/100g) and butyric (0 to 0.057 g/100g), that are produced during the natural fermentation of cassava starch. Results showed large variation among samples, even within the same region. Some samples exhibited high acid levels, mainly lactic acid, but in these neither propionic nor butyric acids were detected. Absence of butyric acid was not expected because this is an important component of the sour cassava starch aroma, and the lack of this acid may suggest that such samples were produced without the natural fermentation step.

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The egg quality may be influenced by some nutrients added to laying hens diets and among these nutrients, the ascorbic acid is included. According to some researches, this acid, besides of improving the quality, it can increase the egg production and weight. In addition, it reduces the quantity of cracked eggs and food intake. In order to contribute with more information, this experiment was developed. Concentrations of 100; 150 and 200mg/kg of ascorbic acid were added to rations of laying hens during 60 days, with the objective of determining the influence of ascorbic acid on the quality of eggs kept under room temperature conditions (26.7 ± 2.2°C and 60 ± 5% moisture) for a period of 28 days. A total of 1440 eggs were used, being 720 of white shell and 720 of brown shell. Egg quality was determined by Haugh unit and yolk index, every 7 days. The obtained results allowed to conclude that ascorbic acid, independent on the level of supplementation, was not enough to decrease.

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The 10-HDA content in Brazilian samples (São Paulo State) of royal jelly (RJ) was analyzed using an HPLC method based on the work by BLOODWORTH et al. [2]. The chromatographic conditions were: isocratic system, reversed phase C18-H column, auto sampler, diode array UV-VIS detector adjusted to 225nm, mobile phase composed by methanol/water (45:55) at pH= 2.5 adjusted with phosphoric acid; a-naphtol was used as internal standard, and the running time was 30min. By statistical analysis of the results, the 10-HDA contents of the samples analyzed seem to have two ranges: 1.8% and 3% (w/w), that would be useful to qualify the RJ. This is the first data regarding 10-HDA content of Brazilian RJ.

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The thermotolerant capacity of several lactic acid bacteria strains isolated from cooked commercial sausages was determined. Four strains were positively identified as Lactobacillus plantarum, Lactobacillus curvatus, Pediococcus pentosaceus and Pediococcus acidilacti, after surviving thermal treatment (70 °C during 60 minutes). Thermotolerant strains were inoculated in sausage batters before cooking in order to determine their effect on color, texture, acceptance and inhibition of Enterobacteria during 12 days at 8 °C. No significant effect of the inoculated strains was detected on color parameters. Textural profile parameters, cohesiveness and resilience, were not affected by the inoculation of thermotolerant lactic acid bacteria, but L. curvatus sausages resulted softer than the rest of the treatments. Samples inoculated with L. curvatus also obtained the lowest scores for the sensory attributes evaluated, with the remaining treatments causing no unfavorable effects on sausage acceptance. There was a reduction in enterobacterial counts after 12 days of cold storage in inoculated samples. The performance of inoculated lactic acid bacteria strains can be explained in a similar way as that of starter cultures in dry-fermented sausages, where the growth in nests impairs other pathogenic microorganisms present in the rest of the sausage, since environmental conditions and the early inoculation of these thermotolerant strains favor them to become the dominant flora.

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Changes in the profile of volatile compounds after the heating of refined soybean oil without adding antioxidants, and treated with quercetin and chlorogenic acid (5-CQA) were investigated by GC/FID, GC/MS, and GC/SNIFFING. The heating temperature of the oil sample was 20 °C for the first minute, and then it was increased up to 160 °C at the rate of 10 °C min-1. The final temperature was kept for 10 minutes. 19 volatiles were identified in the heated samples without antioxidants. Medium-chain carbonyls predominated in the volatile fraction, mainly 2-heptenal, 2,4-heptadienal and 2,4-decadienal. Around 11 to 15 volatile compounds were detected in the heated samples treated with 5-CQA and quercetin, respectively. 5-CQA was not very efficient in delaying the formation of oxidative volatile compounds. The samples quercetin presented lower proportion of carbonyls with C6-C9.. The GC peak area data were used as an approach to estimate the relative content of each volatile compound and indicate that the samples treated with quercetin (p < 0.05) had significantly lower values for, 1-pentanol, 2,4-heptadienal, and 2,4-decadienal compared with those without antioxidants and treated with 5-CQA. GC/SNIFFING analysis revealed a smaller odor perception in the samples treated with 5-CQA compared to those without antioxidants. No odor was perceived in the heated samples treated with quercetin. These results indicate greater effectiveness of quercetin in delaying the formation of oxidative volatile compounds in soybean oils subjected to mild heating conditions. Apparently, biopolyphenols used in the present work showed good oxidative stability since no new volatile compound was detected in the heated samples treated with them.

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Commercial cashew apple juice is widely accepted in the Brazilian market. Cashew apple has high content of ascorbic acid, an important nutrient to human beings. Ascorbic acid content in food can be affected by processing and storage conditions. Commercial cashew apple juice samples, ready-to-drink and concentrated, were analyzed. The ascorbic acid content, total titratable acidity, total soluble solids, and pH of the juices were determined during storage at 4 °C after the containers were opened. The ascorbic acid content presented a great variability among the samples analyzed ranging from 37.3 to 46.3 mg.100 mL-1 in ready-to-drink juices and from 75.7 to 152 mg.100 mL-1 in concentrated juices. The storage of commercial cashew apple juices for 48 hours at 4 °C resulted in ascorbic acid losses of up to 8.8% for concentrated and 6.4% for ready-to-drink juices. The other parameters remained stable during storage. The results of this study point to the importance of considering ascorbic acid losses in commercial cashew apple juices which occurs after opening but before the expiration date expires.

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The objective of this work is to investigate the production of fatty acid ethyl esters from soybean oil in compressed propane using a non-commercial lipase from Yarrowia lipolytica and two commercial ones as catalysts, Amano PS and Amano AY30. The experiments were performed in the temperature range of 35-65 °C. at 50 bar, enzyme concentration of 5 wt%, oil to ethanol molar ratio of 1:6 and 1:9, and solvent to substrates mass ratio of 2:1 and 4:1. The results indicated that low reaction conversions were generally obtained with the use of commercial and non-commercial lipases in pressurized propane medium. On the other hand, the aspects of low solvent to substrates mass ratio and mild temperature and pressure operating conditions used to produce ethyl esters justify further investigations to improve reaction yields.

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In a fish paste made with cooked Brazilian flathead (Percophis brasiliensis), glycerol (17%), sodium chloride (1.5%) and potassium sorbate (0.1%) the following acid percentages: 0.2; 0.4; 0.6; 0.8, 1 and 1.5% w/w were incorporated to determine the relationship between added acetic acid and the sensorially perceived intensity, and the effects of the combination of sweet-acid tastes. Tests for paired comparison, ranking and structured verbal scales for sweet and acid attributes and psychophysical test were carried out. There was a perceptible difference among samples for differences of 0.4 units of acid concentration. Samples indicated as sweeter by 89.47% of the judges were those containing a lesser acid concentration. A reduction in glycerol sweetness when increasing acid levels was observed. Acetic acid reduced the sweetness of glycerol and inversely glycerol reduced the acidity of acetic acid. The data obtained with the magnitude estimation test agree with Steven's law.

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This work aimed to evaluate the effects of the consumption of two commercial conjugated linoleic acid (CLA) mixtures on lipid content and liver histology of healthy rats. The investigation was carried out using thirty rats divided into three groups: C (control), AE (AdvantEdge®CLA), and CO (CLA One®). The concentration of CLA was 2% of feed consumption, and the animals were supplemented daily for 42 days. The total lipid content of the liver was determined, and the histology of the organ was examined by Transmission Electronic Microscopy. The results of total liver lipid contents did not exhibit significant differences between the groups. With regard to hepatic histology, it was observed that although fat globules were visibly present in higher numbers and bigger size in the CLA groups, the organ histology was considered normal since both cytoplasm and organelles showed integrity. It was concluded that even though liver microscopic images indicated the presence of fat globules in the liver, from a statistical point of view, the supplementation for 42 days did not bring about lipid accumulation, nor did it alter hepatic histology.

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The germ fraction with pericarp (bran) is generated in the industrial processing of corn kernel, and it is used for oil extraction and animal feed. This study evaluated the nutritional and protein quality of this fraction in relation to whole corn. The proximate composition, mineral contents, and amino acid profile of the germ fraction with pericarp and of whole corn were determined. A 4-week experiment was conducted using 36 weanling male Wistar rats, and three 10%-protein diets (reference, germ with 15% lipids and casein with 15% lipids), two 6%-protein diets (whole corn and casein), and a protein-free diet were prepared. The germ showed higher contents of proteins, lipids, dietary fiber (27.8 g.100 g-1), ash, minerals (Fe and Zn- approximately 5 mg.100 g-1), and lysine (57.2 mg.g-1 protein) than those of corn. The germ presented good quality protein (Relative Protein Efficiency Ratio-RPER = 80%; Protein Digestibility-Corrected Amino Acid Score-PDCAAS = 86%), higher than that of corn (RPER = 49%; PDCAAS = 60%). The corn germ fraction with pericarp is rich in dietary fiber, and it is a source of good quality protein as well as of iron and zinc, and its use as nutritive raw material is indicated in food products for human consumption.

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Citric fruits - in natura, as frozen pulp or even as juice - are one of the most important Brazilian exportation products. They are a source of ascorbic acid - a potent antioxidant, and pectin, which is used in the food industry and is an important dietary fiber. This project aims to quantify ascorbic acid and pectin contents in citric fruits, commercial oranges and tangerines, comparing them in sizes and varieties. Ascorbic acid amount was measured in juice comparing sizes, varieties and storage conditions, using a tritimetric method with 2.6-dichlorobenzenoindophenol indicator. Total and soluble pectin in each part of the fruits (peel, albedo, pulp and juice) were quantified using the polygalacturonic acid as a standard. Differences were found between the sizes. The highest content of vitamin C was found in the oranges (Bahia variety). Comparing the storage temperatures, the biggest loss was at room temperature. Albedo presented the highest content of pectin in all fruits. In juice, the total and soluble pectin contents increased as fruits size decreased. Oranges and tangerines differed in the amount of pectin

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Buriti and patawa are two endemic palm trees from the Amazon region. Their pulps are traditionally consumed by the local population, but are underused and lesser known worldwide. Nutritional composition, fatty acid and tocopherol contents of the two palm pulps were determined by modern analytical methods: Gas Chromatography (CG) and High Performance Liquid Chromatography (HPLC), based on the standards of AOCS (AMERICAN..., 2002) and AOAC (ASSOCIATION..., 1997), respectively. Buriti and patawa fruit pulps are highly nutritive, with respectively, high fat content (38.4% and 29.1% of dry matter (DM)), protein content (7.6% and 7.4% of DM) and dietary fibers (46% and 44.7% of DM). Buriti pulp can be considered healthy food due its high content of vitamin E (1169 µg.g-1 DM). Patawa pulp is highly oleaginous and its fatty acid composition is very similar to the ones of healthy oils, such as olive oil.

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This study aimed to characterize Tamarindus indica L. seeds regarding its composition and to evaluate its antioxidant potential, fatty acid profile and content of tocopherols. In order to obtain the extract, the dried and crushed seeds were extracted with ethanol for 30 minutes in a 1:3 seeds: ethanol ratio under continuous stirring at room temperature. After that, the mixtures were filtered and subjected to roto-evaporation at 40 ºC in order to determine, through direct weighing, the dry matter yields of the extracts. According to the results, Tamarindus indica L. seeds showed high content of total carbohydrates (71.91%) and offered relevant content and antioxidant activity of phenolic compounds. Tamarindus indica L. seeds oil presents high oxidative stability (15.83 hours) and significant total tocopherol content (57.77 mg.kg-1), besides presenting a higher percentage of unsaturated fatty acids - the main component being linolenic (59.61%), which is considered an essential fatty acid.