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1.
Dietary fish oil supplementation increases the content of n-3 polyunsaturated fatty acids (PUFA) in cellular membranes. The highly unsaturated nature of n-3 PUFA could result in an enhanced lipid peroxidation in the oxidative environment characteristic of asthma. The oxidative reaction cascade culminates in an increased production of components associated to oxidative stress and of an important proinflammatory mediator platelet-activating factor (PAF)-like lipid. We evaluated the effect of fish oil supplementation in asthmatic rats upon the PAF bioactivity and parameters related to oxidative stress in the lung. Fish oil supplementation of asthmatic rats resulted in lower concentrations of nitrite (1.719 ± 0.137 vs. 2.454 ± 0.163 nmol/mL) and lipid hydroperoxide (72.190 ± 7.327 vs. 120.200 ± 11.270 nmol/mg protein). In asthmatic animals, fish oil increased the activities of superoxide dismutase (EC 1.15.1.1) (33.910 ± 2.325 vs. 24.110 ± 0.618 U/mg protein) and glutathione peroxidase (EC 1.11.1.9) (164.100 ± 31.250 vs. 12.590 ± 5.234 U/mg protein). However, fish oil did not affect PAF bioactivity in lung tissue of asthmatic rats (0.545 ± 0.098 340/380 vs. 0.669 ± 0.101 340/380 nm ratio). Considering the two-step process—oxidative stress and PAF bioactivity—fish oil exhibited a divergent action on these aspects of asthmatic inflammation, since the supplement lowered oxidative stress in the lungs of asthmatic rats, presenting an antioxidant effect, but did not affect PAF bioactivity. This suggests a dual effect of fish oil on oxidative stress and inflammation in asthma.  相似文献   

2.
A comparative study was carried out in order to evaluate the kinetics of the formation of a number of primary and secondary oxidation products during oxidation of olive oil in the Rancimat test at 100–130 °C. There were good correlations between the Rancimat index (OSI) and stability indices (IP) measured in the Rancimat test with no significant differences in kinetic parameters calculated from them. Mean values of the temperature coefficient, Q10 number, activation energy (Ea), frequency factor (A), and free energy of activation (ΔG++) for olive oil oxidation were calculated to be ?3.44 × 10?2°C?1, 2.21, 98.91 kJ/mol, 12.17 × 1012 h?1, and 128.25 kJ/mol, respectively. Each unit change in Ea was accompanied by an average 1.43 × 1012 change in A, indicating a higher contribution for factor A than for Ea to the olive oil stability. The Ea and A correlated well with the values of enthalpy and entropy, respectively. The values of OSI or IP could be described well by the ΔG++ values. Kinetic data indicated that olive oil stability is more affected by the indigenous antioxidants than by the fatty acid composition.  相似文献   

3.
Oxidative stability (OS) of virgin olive oil is affected by different antioxidants whose levels may be influenced by nutrients availability. Changes in OS of virgin olive oil and antioxidants levels were evaluated according to foliar application of six nutrient-based treatments: T1 (rich in nitrogen), T2 (rich in boron, magnesium, sulfur and manganese), T3 (rich in phosphorus and potassium), T4 (rich in phosphorus and calcium), T5 (application of T1 and T2) and T6 (application of T1, T2, T3 and T4). The foliar applications were carried out during two successive growing seasons and oils were extracted and analyzed at the end of the experiment (after 2 years). T3 and T6 treatments improved oil stability by increasing the content of antioxidants, while T2 and T4 affected negatively the antioxidant profile of oils. Measured correlations between OS and compositional variables showed that total phenols had the highest value (R = 0.937, p < 0.001), followed by α-tocopherol (R = 0.775, p < 0.001) and oleic/linoleic ratio (R = 0.625, p < 0.05). These findings suggest that the changing levels of antioxidant compounds, due to fertilization, may be used to obtain oils with the highest quality.  相似文献   

4.
Dietary fatty acids are suggested to affect oxidative stress; however, results from interventions have been inconclusive. The aim was to examine if fatty fish, lean fish, and Camelina sativa oil (CSO) affect the urinary prostanoid levels in subjects with impaired glucose metabolism. Altogether 79 participants aged 43–72 years completed a randomized controlled study lasting 12 weeks. There were four parallel groups, fatty fish, lean fish (four fish meals/week in both), CSO providing 10 g/day alpha-linolenic acid (ALA), and control diet with limited fish and ALA containing oil consumption. Urinary prostanoids (prostaglandin F, 5-F2t-isoprostanes and 15-F2t-isoprostane metabolites, isofuran, 8-F3t-isoprostanes, and 4 - (RS)-4-F4t-neuroprostane) of 72 participants (age: mean (±SD) 58.9 ± 6.5 years; body mass index: 29.3 ± 2.5 kg/m2) collected over 12-h were measured using liquid chromatography tandem-mass spectrometry. Plasma phospholipid fatty acids were determined using gas chromatography. Our study showed that the proportion of ALA in plasma phospholipids increased in the CSO group (overall difference among the groups p-value <0.001). In the fatty fish group, proportions of eicosapentaenoic and docosahexaenoic acids increased (overall p-value <0.001 for both). Prostaglandin F was higher in the CSO group than in the control group (p < 0.05), however, there were no other significant changes in urinary excretion of other prostanoids among the study groups. At baseline, arachidonic acid in plasma phospholipids was positively (r = 0.247, p < 0.05) and ALA negatively (r = −0.326, p < 0.05) associated with urinary total isoprostanes. In conclusion, CSO, fatty fish, and lean fish consumption do not cause major changes in oxidative stress markers in subjects with impaired glucose tolerance.  相似文献   

5.
Changes in olive properties and oil quality, oxidative stability, phenolic and chemical composition of two common Turkish varieties (Memecik and Edremit) during maturation were investigated. Olive samples were collected in their own growing region for five different harvest dates and processed to oil with a laboratory scale mill. Metabolic behaviors of these two varieties along with the maturation were different in terms of some compositional parameters. Oleic acid, triolein, β-sitosterol, oleuropein, hydroxytyrosol, and tyrosol contents of olive or olive oils fluctuated with maturation. However, changes in average weight, flesh/pit ratio, water and oil contents of the olives were observed. Phenolics such as trans cinnamic acid contents of both olive fruits decreased whereas cyanidin 3-O-glucoside and cyanidin 3-O-rutinoside anthocyanins increased. Free fatty acids of virgin olive oils were found independent of maturity although some slight changes were determined in peroxide value, dien and trien conjugations. Some compositional parameters such as pigment concentration, tocopherols, stearic acid, linolenic acid, palmitodiolein and monounsaturated/polyunsaturated fatty acid ratio decreased while linoleic acid, dioleolinolein, palmitooleolinolein and Δ-5-avenasterol percentages increased with the maturation. A clear discrimination was observed with principal component analysis. The data obtained can also be considered useful for providing information to determine the ideal maturity stage.  相似文献   

6.
Episodes of acute exacerbation are the major clinical feature of asthma and therefore represent an important focus for developing novel therapies for this disease. There are many reports that the n-3 fatty acids found in fish oil exert anti-inflammatory effects, but there are few studies of the action of fish oil on airway smooth muscle (ASM) function. In the present investigation, we evaluated the effect of fish oil supplementation on smooth muscle force of contraction in ovalbumin-induced asthmatic Wistar rats, and its consequences on static lung compliance, mucus production, leukocyte chemotaxis and production of proinflammatory cytokines. Fish oil supplementation suppressed the infiltration of inflammatory cells into the lung in asthmatic animals (2.04 ± 0.19 × 106 cells vs. 3.33 ± 0.43 × 106 cells in the control asthmatic group; P < 0.05). Static lung compliance increased with fish oil supplementation in asthmatic rats (0.640 ± 0.053 mL/cm H2O vs. 0.399 ± 0.043 mL/cm H2O; P < 0.05). However, fish oil did not prevent asthma-associated lung eosinophilia and did not affect the concentrations of tumor necrosis factor-α and interleukin-1β in lung tissue or the proportion of the airways obliterated with mucus. Fish oil had no effect on the force of contraction in asthmatic rats in response to acetylcholine (3.026 ± 0.274 mN vs. 2.813 ± 0.364 mN in the control asthmatic group). In conclusion, although fish oil exerts some benefits in this model of asthma, its effectiveness appears to be limited by an inefficient action on airway smooth muscle function.  相似文献   

7.
A total of 297 single-varietal olive oil samples collected from four California regions (Central Valley, Wine Country, South Coast, and Desert) were analyzed on the fatty acid (FA) and sterol compositions between 2010 and 2017. Significantly higher amounts of palmitic acid (PAM), palmitoleic acid, and total sterols were detected in varieties including Arbequina, Arbosana, Picual, Leccino, and Koroneiki from the Desert region. Two super-high density varieties Arbequina and Koroneiki from the Desert region had a significantly higher campesterol content (5.3 ± 0.2 and 4.7 ± 0.1%, respectively) compared to the same varieties from the Wine Country and the South Coast, not meeting the limit of the existing California olive oil standards [Correction added on 8 March 2019 after first online publication: the preceding sentence has been updated to reflect the correct campesterol content.]. The impact of severe droughts in California during late 2011 and 2014 on the major FA and sterol compositions of California olive oil was also analyzed. Multivariate chemometrical tools, one-way ANOVA and principle component analysis (PCA), confirmed the significant differences between samples from the Desert region and other growing regions among several varieties and achieved desirable segregation on the PCA biplots for variety-region classification. This study demonstrates a feasible approach of olive oil composition database establishment for new olive-growing regions; the proposed chemometrical method can be used to characterize unknown variety of olive oils produced from different regions in California; and the collected FA and sterols data provide information for revision recommendations to the current olive oil standards.  相似文献   

8.
Marine phospholipids (PL) are potential ingredients for food fortification due to its numerous advantages. The main objective of this study was to investigate whether a fermented milk product fortified with a mixture of marine PL and fish oil had better oxidative stability than a fermented milk product fortified with fish oil alone. Fortification of a fermented milk product with marine PL was performed by incorporating 1 % w/w lipids, either in the form of neat oil or in the form of a pre-emulsion. Lipid oxidation was investigated in the neat emulsions and fortified products by the measurements of primary, secondary volatile oxidation products and tocopherol content upon 32 days storage at 2 °C and 28 days storage at 5 °C, respectively. Analyses of particle size distribution, viscosity and microbial growth were also performed. In addition, sensory attributes such as sour, fishy and rancid flavor/odor were evaluated in fortified products by a trained panel. The results obtained showed that incorporation of a mixture of marine PL and fish oil into fermented milk products decreased the oxidative stability and sensory quality of fortified products. The pH-dependent behavior of iron seemed to be the main factor that influenced the lipid oxidation in the marine PL emulsion and fermented milk system. In addition, both oxidative stability and sensory acceptability of fortified products varied depending on the quality of the marine PL used for fortification.  相似文献   

9.
The main objective of this study was to evaluate the effect of different deficit irrigation treatments (control, regulated deficit irrigation [RDI]‐1, RDI‐2, and RDI‐3) on the phenolic profile of the olive paste and oil content. Irrigation treatments with more stress water led to a considerable increase in the phenolic compounds of olive paste, especially in oleuropein (60.24%), hydroxytyrosol (82%), tyrosol (195%), and verbascoside (223%) compared to control. A significant increase in the content of total flavonoids and phenolic acids was also observed for these samples. In virgin olive oils (VOO) elaborated from the most stressed olive trees (RDI‐2 and RDI‐3), a noticeable increase in phenolic substances with antioxidant properties (oleuropein, hydroxytyrosol, tyrosol, secoiridoid derivatives, and o‐vanillin) was observed. Consequently, water stress conditions improved antioxidant activity of VOO.  相似文献   

10.
The objectives of this work were to study the impact of aromatization by sweet lemon and sweet orange peels on olive oil quality, chemical composition and heat stability. Flavored olive oils were prepared by maceration of sweet lime and sweet orange zests at 1, 3 and 5 %. The oil samples were kept at 60 °C for 40 days. Physicochemical tests (FFA, PV, oxidative stability, polyphenols and pigments contents) were carried out. The antioxidant activity (β‐carotene‐linoleate bleaching assay, DPPH radical scavenging and reducing power) was also tested. Results indicated that the addition of citrus zests contributed to the increase in polyphenols and carotenoids contents. Moreover, it led to an increase in the DPPH‐radical scavenging activity (99.50 % for flavored olive oil with sweet orange zests at 5 %). Flavored olive oils with sweet orange zests were more stable to heat treatment than those flavored with sweet lemon zests. The degradation rate of bioactive compounds was lower for virgin olive oil comparing to flavored oils.  相似文献   

11.
Inflammation and oxidative stress are thought to be involved in, or associated with, the development of obesity, dyslipidemia, hepatic steatosis, and insulin resistance. This work was designed to determine the evolution of inflammation and oxidative stress during onset and progression of hepatic steatosis and glucose intolerance. Seventy-five male Wistar rats were divided to control and high-fat high-fructose (HFHFr) groups. A subgroup of each group was sacrificed at 4, 8, 12, 16, and 20 weeks. HFHFr-fed rats exhibited overweight, glucose intolerance, and hepatic steatosis with increased contents of hepatic diacylglycerols and ceramides. The HFHFr diet increased hepatic interleukin 6 (IL-6) protein and adipose tissue CCL5 gene expression and hepatic nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity but not mitochondrial reactive oxygen species (ROS) production. The HFHFr diet decreased plasma and liver levels of isoprostanoid metabolites as well as plasma thiobarbituric acid-reactive substance (TBARS) levels. Hepatic glutathione content was decreased with a moderate decrease in superoxide dismutase (SOD) and glutathione peroxidase (GPx) with the HFHFr diet. Overall, HFHFr diet led to hepatic lipid accumulation and glucose intolerance, which were accompanied by only moderate inflammation and oxidative stress. Most of these changes occurred at the same time and as early as 8 or 12 weeks of diet treatment. This implies that oxidative stress may be the result, not the cause, of these metabolic alterations, and suggests that marked hepatic oxidative stress should probably occur at the end of the steatotic stage to result in frank insulin resistance and steatohepatitis. These findings need to be further evaluated in other animal species as well as in human studies.  相似文献   

12.
Asthma oxidative stress disturbances seem to enable supplementary proinflammatory pathways, thus contributing to disease development and severity. The current study analyzed the impact of two types of oral vitamin D (VD) supplementation regimens on the redox balance using a murine model of acute ovalbumin-induced (OVA-induced) asthmatic inflammation. The experimental prevention group received a long-term daily dose of 50 µg/kg (total dose of 1300 µg/kg), whereas the rescue group underwent a short-term daily dose of 100 µg/kg (total dose of 400 µg/kg). The following oxidative stress parameters were analyzed in serum, bronchoalveolar lavage fluid (BALF) and lung tissue homogenate (LTH): total oxidative status, total antioxidant response, oxidative stress index, malondialdehyde and total thiols. Results showed that VD significantly reduced oxidative forces and increased the antioxidant capacity in the serum and LTH of treated mice. There was no statistically significant difference between the two types of VD supplementation. VD also exhibited an anti-inflammatory effect in all treated mice, reducing nitric oxide formation in serum and the expression of nuclear factor kappa B p65 in the lung. In conclusion, VD supplementation seems to exhibit a protective role in oxidative stress processes related to OVA-induced acute airway inflammation.  相似文献   

13.
Seventy samples sold in the Brazilian market as extra virgin olive oil (EVOO) were evaluated for the presence of the 13 polycyclic aromatic hydrocarbons (PAH) classified as carcinogenic and genotoxic by the Joint FAO/WHO Expert Committee on Food Additives (JECFA), to verify if the products were adulterated and to evaluate if there is a correlation between PAH presence and adulteration. PAH were detected in 93% of the samples, with summed levels varying from not detected to 41.10 μg/kg. Five samples showed BaP concentration above acceptable levels set by European legislation and by Brazilian regulation (2.0 μg/kg) and 7 presented PAH4 levels above the limit set by European legislation (10.0 µg/kg). The levels of fatty acid composition, sterols content, stigmastadiene and specific extinction did not comply with both Brazilian and International Olive Council (IOC) standards in 18, 31, 30 and 21% of the samples, respectively. The tolerance levels for these analyses in the Brazilian standards are 55.0–83.0 g/100 g (oleic acid), 3.5–21.0 g/100 g (linoleic acid), ≤0.05 g/100 g (trans-oleic acid), ≤0.05 g/100 g (trans-linoleic + trans-linolenic acid), ≤0.15 mg/kg (stigmastadiene), ≤2.50 (K232), ≤0.22 (K270), ≤0.01 (?K), 1000–1600 mg/kg (Σ sterols). Results indicate that 19 samples were adulterated. According to principal component analysis, samples were distinguished as: (1) EVOO with addition of vegetable oil from another source, (2) EVOO with addition of refined oil and (3) samples possibly not adulterated. The variable ΣPAH was related mainly to samples of EVOO with addition of vegetable oil from another source.  相似文献   

14.
We introduce a visible Raman spectroscopic method for determining the free fatty acid (FFA) content of extra virgin olive oil with the aid of multivariate analysis. Oleic acid was used to increase the FFA content in extra virgin olive oil up to 0.80% in order to extend the calibration span. For calibration purposes, titration was carried out to determine the concentration of FFA for the investigated oil samples. As calibration model for the FFA content (FFA%), a partial least squares (PLS) regression was applied. The accuracy of the Raman calibration model was estimated using the root mean square error (RMSE) of calibration and validation and the correlation coefficient (R 2) between actual and predicted values. The calibration curve of actual FFA% obtained by titration versus predicted values based on Raman spectra was established for different spectral regions. The spectral window (945–1600 cm−1), which includes carotenoid bands, was found to be a useful fingerprint region being statistically significant for the prediction of the FFA%. High R 2 and small RMSE values for calibration and validation could be obtained, respectively.  相似文献   

15.
16.
The characteristics of eight varieties of virgin olive oil (Arbosana, Arbequina, Coratina, Cornicabra, Frantoio, Koroneiki, Picual, and Ezhi 8) obtained in two successive crops in the southwest of China (Xichang, Sichuan Province) were investigated. Significant differences (P < 0.05) were observed in physicochemical properties, fatty acid profile, minor component contents, and oxidative stability between different varieties of olive oils. The physicochemical properties of all samples met IOC standards for extra virgin olive oil, while in Koroneiki, olive oils were present the optimum oxidation stability among studied varieties. The results of hierarchical cluster analysis and principal component analysis (PCA) showed a good classification between varieties based on their qualitative characteristics. Koroneiki and Ezhi 8 olive oils were significantly different from other varieties mainly due to color, fatty acid profile, and minor components. PCA result also showed that harvest crop influences the characteristics of samples mainly due to the variance of temperature and rainfall.  相似文献   

17.
Hyperlipidemia is a common cardiovascular disease. At present, the influence of high fat diet (HFD) on this is being explored. Recently, vegetable oils rich in omega‐3 have been reported that can treat hyperlipidemia caused by HFD. However, the effects of chia seed oil (CSO) on HFD‐induced hyperlipidemia and oxidative stress are poorly studied. Hence, in this study, the effects of CSO on hyperlipidemia and oxidative stress induced by HFD in mice are analyzed by various commercial kits, section staining, and protein expression. The results show that CSO decreases body weight and organ index. Meanwhile, CSO reduces serum lipid levels of total cholesterol, triglyceride, and low‐density lipoprotein cholesterol. It can also elevate superoxide dismutase and glutathione peroxidase activities and reduce malondialdehyde content in serum and liver. The results of histopathological analysis prove that CSO improves hepatic steatosis and reduces lipid deposition. Further, the results of western blot demonstrate that CSO upregulates the expression of peroxisome proliferator‐activated receptor alpha and carnitine palmitoyltransferase 1a in the liver. As a result, CSO may be a potential lipid‐lowering oil to prevent and treat HFD‐induced hyperlipidemia and oxidative stress. Practical Applications CSO, as a byproduct of chia seed processing, is a rich source of α‐linolenic acid. This study investigates the effects of CSO on HFD‐induced hyperlipidemia and oxidative stress in mice. It is concluded that dietary CSO can improve the hyperlipidemia in HFD‐induced mice via analysis of lipid parameters, histopathology study of the liver, and lipid metabolism related genes. In addition, supplementation of CSO also can improve the oxidative stress in mice. Therefore, CSO can be used for the prevention of hyperlipidemia and oxidative stress. This research provides a theoretical basis for the comprehensive development and utilization of functional chia seed oil.  相似文献   

18.
Ceramides, composed of a sphingosine and a fatty acid, are bioactive lipid molecules involved in many key cellular pathways (e.g., apoptosis, oxidative stress and inflammation). There is much evidence on the relationship between ceramide species and cardiometabolic disease, especially in relationship with the onset and development of diabetes and acute and chronic coronary artery disease. This review reports available evidence on ceramide structure and generation, and discusses their role in cardiometabolic disease, as well as current translational chances and difficulties for ceramide application in the cardiometabolic clinical settings.  相似文献   

19.
The main objective of this work was to study the effects of foliar biofertilizers on individual volatile profiles and phenolic compounds of olive oil (Olea europaea L. cv. Chemlali). Three foliar biofertilizers were used in two successive application seasons: T1 (rich in nitrogen, phosphorus and potassium); T2 (rich in calcium); and T3 (application of both T1 and T2). Results showed that foliar fertilization with T2 increased the phenolic compound contents (e.g., oleuropein aglycone and decarboxymethyl ligstroside aglycone) of Chemlali olive oil. It also enhanced the levels of many volatile compounds responsible for the good flavor of olive oil such as hexanal. However, T1-tested fertilizer led to a significant decrease in the content of phenolic compounds, although they seemed to improve significantly the levels of the majority of volatile compounds, especially hexanal. Based on these results, a significant relationship between plant nutrition and quality of oil was observed. Our results demonstrated a potential positive influence on the concentration of sensory quality compounds under T2 (Ca2+-based fertilizer). This result should be considered in the design of foliar nutrient application management strategies for olive trees.  相似文献   

20.
A series of authentic virgin, refined, and mixtures of olive oils was analyzed for their content of 2-and 3-chloropropanediol (MCPD) esters expressed as 2−/3-MCPD, glycidol (and related glycidyl esters) (GE), and diglycerides (DAG). High concentrations of MCPD and GE were found, above all, in pomace oils, which come from the poorer starting raw materials, while virgin olive oils, as expected, do not contain any process contaminant. On the other hand, DAGs are present in all samples, demonstrating that their involvement in the formation of such contaminants only occurs when temperatures are higher than that used during the refining steps. The lack of correlation between the amounts of MCPD and GE can be ascribed to their completely different chemical stability as the epoxy ring of the GE opens easily, leading to both short-chain derivatives and/or MCPD itself. This finding can also explain the data about the absence of 2-MCPD in all the analyzed oil samples: other than the statistical probability and the steric effect of the SN2 formation mechanism, both in favor of the 3- derivative, we have also to consider the MCPD formation pathway involving glycidol that, under opportune conditions of refining, can increase the whole amount of 3-MCPD (under thermodynamic control, 3-MCPD is more stable).  相似文献   

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