首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 46 毫秒
1.
Fish and fish oils are the richest sources of ω-3 fatty acids. However, they are susceptible to lipid peroxidation due to their high degree of unsaturation. In the present study, the level of thiobarbituric acid reactive material in various fish oils available in the market with and without added Vitamin E was determined. The peroxide levels in fish oil heated to food frying temperature of 180°C and the effect of addition of vitamin E has also been studied. The results indicate that the peroxide levels in almost all the products available in the market were abnormally high irrespective of their Vitamin E content. This might be due to the inefficient methods used for processing and storage of fish oils. Addition of vitamin E was found to have a significant effect in lowering the rate of peroxidation of fish oil during thermal stress, showing that association of antioxidants with ω-3 fatty acids lowers the rate of lipid peroxidation.  相似文献   

2.
 22 kinds of seed oils were extracted from 8 genera of the family Ulmaceae in China The seed oils were examined for their characteristics and fatty acid compositions by gas liquid chromatography.  The fatty acid compositions of these oils were found to fall into two classes. Some genera (such as  Ulmus,  Zelkova)  contain  mainly lower saturated acids, in which the chief acid is capric acid 10:0, while the genera (such as Celtis, Pteroceltis, Aphananthe, Trema, Gironniera) contain mainly unsaturat- ed acids, in which the chief acid is linoleic acid  18:2.  Hemiptelea  davidii  (Hance) Planch contain however either certain amount of short-chain saturated acids or higher unsaturated acids, it appears a intermediate genus between the two classes.  According to the component acids we support that the Ulmaceae be split into two subfamilies. The genera arrangement based on the component acids corresponds basically with the view based on mophological characters and flavonoids found in leaves of Ulmaceae, but there are some discrepancies in certain genera, for example, the Aphananthe should beplaced in Celtoid instead of Ulmoid by the present study.  相似文献   

3.
每一个单一油品虽然各具特点,但都不能达到均衡营养。该方法制取的调和油既突出各类不饱和脂肪酸比例组成的合理性,即油酸：亚油酸：亚麻酸=5：4：1,又突出产品的营养功能,即其中含有较高的维生素E。该比例组成满足了中国营养学会推荐的单不饱和脂肪酸与多不饱和脂肪酸比例相等的要求,又满足了ω-6多不饱和脂肪酸：ω-3多不饱和脂肪酸=4：1的要求。因此是最理想的调和油。  相似文献   

4.
The present study has investigated the levels of lipids, lipoprotein cholesterol (HDL and LDL cholesterol), thiobarbituric acid reactive substances (TBARS) and vitamin E in plasma and erythrocyte membranes of twenty two clinically diagnosed adult rheumatoid arthritis patients and an equal number of age matched healthy subjects. The levels of lipids and lipoprotein cholesterol were markedly reduced in patients with rheumatoid arthritis as compared to healthy subjects. The altered lipid pattern may be related to decreased lipoprotein cholesterol, fatty acids and impairment in antioxidant defence mechanism.  相似文献   

5.
Membrane lipid and protein composition was compared in erythrocytes from iron deficiency anemia (IDA) and heterozygous beta thalassemia patients. The study was planned to correlate the influence of iron deficiency with the intrinsic defect of the heterozygous condition on the membrane structural integrity as well as to investigate whether there are differences in membrane changes between the two conditions. Results indicate high levels of saturated fatty acids and low unsaturated fatty acids in both disorders although arachidonic acid and the unsaturation index were lower in heterozygous thalassemia than IDA. Nevertheless, neither of the conditions provoked any alterations in membrane protein or glycophorin suggesting alterations in the lipid moiety only. Present findings indicate that irrespective to the etiology, both, iron deficiency and the heterozygous condition show a common pattern of lipid derangement, which may in turn result in increased membrane rigidity and decreased cellular deformability.  相似文献   

6.
Docosahexaenoic (DHA) and arachidonic acids (AA) are polyunsaturated fatty acids (PUFAs), major components of brain tissue and neural systems, and the precursors of a number of biologically active metabolites with functions in inflammation resolution, neuroprotection and other actions. As PUFAs are highly susceptible to peroxidation, we hypothesised whether cigarette smokers would present altered PUFAs levels in plasma and erythrocyte phospholipids. Adult males from Indian, Sri-Lankan or Bangladeshi genetic backgrounds who reported smoking between 20 and 60 cigarettes per week were recruited. The control group consisted of matched non-smokers. A blood sample was taken, plasma and erythrocyte total lipids were extracted, phospholipids were separated by thin layer chromatography, and the fatty acid content analysed by gas chromatography. In smokers, dihomo-gamma-linolenic acid, the AA precursor, was significantly reduced in plasma and erythrocyte phosphatidylcholine. AA and DHA were significantly reduced in erythrocyte sphingomyelin. Relatively short term smoking has affected the fatty acid composition of plasma and erythrocyte phospholipids with functions in neural tissue composition, cell signalling, cell growth, intracellular trafficking, neuroprotection and inflammation, in a relatively young population. As lipid peroxidation is pivotal in the pathogenesis of atherosclerosis and neurodegenerative diseases such as Alzheimer disease, early effects of smoking may be relevant for the development of such conditions.  相似文献   

7.
The excessive generation of reactive oxygen species (ROS) by abnormal spermatozoa and contaminating leukocytes has been defined as one of the few etiologies for male infertility. Administration of antioxidants in patients with ‘male factor’ infertility has begun to attract considerable interest. The main difficulty of such an approach is our incomplete understanding of the role of free radicals in normal and abnormal sperm function leading to male infertility. Mammalian spermatozoa membranes are very sensitive to free radical induced damage mediated by lipid peroxidation, as they are rich in polyunsaturated fatty acids. Limited endogenous mechanisms exist to reverse these damages. ROS attacks the fluidity of the sperm plasma membrane and the integrity of DNA in the sperm nucleus. ROS induced DNA damage accelerate the germ cell apoptosis. Unfortunately spermatozoa are unable to repair the damage induced by excessive ROS as they lack the cytoplasmic enzymes required to accomplish the repair. Assessment of such oxidative stress status (OSS) may help in the medical treatment. Treatment strategies must be directed toward lowering of ROS levels to keep only a small amount necessary to maintain normal cell function.  相似文献   

8.
Changes in plasma fatty acid (FA) composition and desaturase activities are observed in metabolic syndrome (MS). However, whether these changes are a reflection of dietary intakes of fats and FAs is not well established. The current study was aimed at assessing plasma FA composition and desaturase enzyme activities as biomarkers of dietary intakes in subjects with MS. Case control study was done on 41 MS patients and was compared with age matched 45 controls. Dietary intakes, anthropometric and clinical parameters were measured. FA composition was analysed using gas chromatography-flame ionisation detector and desaturase enzyme activities were estimated as ratios of product to precursor FAs. Higher levels of 14:0, 16:0, 16:1, 18:1, D9D-18 activity and lower levels of 18:0 and 18:2 n-6 were seen in MS group when compared to controls (p < 0.05). Strong positive correlations were seen between plasma triglyceride (TG) levels and 14:0, 16:0, 16:1, 18:1, total saturated fatty acid, total monounsaturated fatty acid, and D9D activities, while 18:0, 18:2 n-6 and total polyunsaturated fatty acid were negatively correlated with TG. Positive correlations were seen between plasma 14:0, 18:1 and D9D-18 activity with total energy intake and carbohydrate (CHO) intakes but not with fat intake. Plasma FA profile appears to be a better index of total energy intake and CHO intake than fat intake, suggesting it might be a good reflection of endogenous FA metabolism. Changes in FA composition may therefore serve as an early index of dysregulation of FA metabolism, resulting in increased risk of MS.  相似文献   

9.
An adequate antioxidant reserve which is usually present in a vegetarian diet is associated with higher life expectancy. On the other hand habitual consumption of fish is associated with lower risk of cardiovascular diseases which is attributed to the polyunsaturated fatty acids (PUFA) present in it. However the PUFA are readily susceptible to oxidation leading to the formation of free radicals which is known to be involved in the causation of several diseases. The oxidant-antioxidant status of 23 vegetarians and 22 fish eaters was studied by determining the plasma lipid peroxides measured as malondialdehyde (MDA) and the antioxidants, viz. glutathione (GSH), ascorbic acid, ceruloplasmin and uric acid. Results show that the ascorbic acid values were significantly higher in vegetarians. In addition, MDA correlated negatively with ascorbic acid only in vegetarians. However, correlation of MDA with glutathione showed a significant negative correlation only in fish eaters. There was no statistically significant difference in the MDA, GSH, ceruloplasmin and uric acid levels. The mechanism behind these findings are not clear and needs to be explored.  相似文献   

10.
This paper deals with the constituents of fatty acids from the seed oils of Pinaceae in China, including 30 species belonging to 8 genera.  Discovered are three characteristic fatty acids, i.e. Cis-5,9-octadecadienoic acid, Cis-5,9,12-octadecatrienoic acid and Cis-5, 11, 14-eicosatrienoic acid. Based on the data obtained, the distribution of the three characteristic fatty acids in Pinaceae of China is also discussed.  相似文献   

11.
The effect of an intrinsic defect in the red cell and pronounced hypochromia on oxidative damage to RBC membrane lipids was compared in beta-thalassemia and iron deficiency anemia (IDA), which have a varied etiology but equivalent low hemogiobin content. The study was planned to correlate the etiology of the disorders to the severity of lipid imbalance and RBC hemolysis in membranes of both the conditions. Results indicated a fall of lysophosphatidylcholine(LPC), phosphatidylethanolamine(PE) and the unsaturated to saturated fatty acid ratio in both conditions, while phosphatidylcholine(PC) increased only in thalassemia. However, irrespective of the disease, sphingomyelin(SM), total cholesterol and phospholipid levels elevated and the hydrogen peroxide stress test indicated increased susceptibility of both pathologic RBCs to peroxidation. Present findings indicate that IDA and thalassemla, allow for considerable amounts of oxidative damage to membrane lipids, irrespective of their etiologles, and thus point hypochromia as an important contributor for inducing lipid imbalance and RBC hemolysis.  相似文献   

12.
The beneficial effects of ∈-3 fatty acids on human health have been well documented. Fish and fish oils are the richest sources of ∈-3 fatty acids. However, due to their high degree of unsaturation, they are highly susceptible to lipid peroxidation. Regular consumption of peroxidised oils may represent a risk factor for the induction and development of atherosclerosis. In view of the above reports, it was considered necessary to study the effects of tumeric on fish lipid peroxidation during standard cooking practices and on time-dependent changes in the peroxidation of fish homogenate. The antioxidant effect of α-tocopherol was also studied to confirm the relevance of the study. The results suggest that turmeric may be considered as a safe, cheap and readily usable antioxidant for food preparations.  相似文献   

13.
To test the concept of intense psychogenic stress manifesting as organic lesion, effect of pre-operative stress on serum lipid peroxide levels in 30 otherwise healthy patients to undergo major abdominal elective surgery has been studied and compared with healthy controls. Significant elevations in serum lipid peroxide levels both on hospitalization and at pre-operative stage were noticed in comparison with healthy controls. However, serum lipid peroxide levels at pre-operative stage did not show significant fluctuations in comparison with those at the time of admission, suggestive of no probable further increment in autoxidation of unsaturated fatty acids of membrane lipids and proper handling by scavenging enzyme system.  相似文献   

14.
Oxidative stress in Parkinson’s disease   总被引：1，自引：0，他引：1  
Oxidative stress contributes to the cascade, leading to dopamine cell degeneration in Parkinson’s disease. However, oxidative stress is intimately linked to other components of the degenerative process, such as mitochondrial dysfunction, excitotoxicity, nitric oxide toxicity and inflammation. It is therefore difficult to determine whether oxidative stress leads to or is a consequence of, these events. Oxidative stress was assessed by estimating lipid peroxidation product in the form of thiobarbituric acid reactive substances, nitric oxide in the form of nitrite & nitrate. Enzymatic antioxidants in the form of superoxide dismutase, glutathione peroxidase, catalase, ceruloplasmin and non enzymatic antioxidant vitamins e.g. vitamin E and C in either serum or plasma or erythrocyte in 40 patients of Parkinson’s disease in the age group 40–80 years. Trace elements e.g. copper, zinc and selenium were also estimated. Plasma thiobarbituric acid reactive substances and nitric oxide levels were Significantly high but superoxide dismutase, glutathione peroxidase, catalase, ceruloplasmin, vitamin-E, vitamin-C, copper, zinc and selenium levels were significantly low in Parkinson’s disease when compared with control subjects. Present study showed that elevated oxidative stress may be playing a role in dopaminergic neuronal loss in substentia nigra pars compacta and involved in pathogenesis of the Parkinson’s disease.  相似文献   

15.
The main objective of the study was to assess the oxidative stress in plasma and erythrocytes of rheumatoid arthritis patients by measuring the levels of thiobarbituric acid reactive substances (TBARS), non-enzymatic antioxidants (vitamin E, C and reduced glutathione) and enzymatic antioxidants [superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSHPx)]. This study has been conducted on twenty-two adult female rheumatoid arthritis patients and an equal number of healthy subjects. Elevated lipid peroxidation and multidirectional changes in the antioxidant defence system were noticed in patients with rheumatoid arthritis. The enhanced lipid peroxidation accompanied by disturbance in antioxidant status indicates that rheumatoid arthritis patients are more prone to free radical mediated oxidative damage.  相似文献   

16.
The hyperlipidemia, fatty liver and the high levels of liver and kidney thiobarbituric acid reactive substances (TBARS) observed in rats which were fed ethanol for 45 days, could be significantly reduced by feeding diacetodibutyl disulphide (DADBDS). Ethanol-induced hypoproteinemia and the rise in serum enzymes like AST (EC 2.6.1.10), ALT (EC 2.6.1.2) and ALP (EC 3.1.3.1) could also be ameliorated by DADBDS. Feeding of this compound to normal rats did not produce any change in serum or tissue lipid levels or serum enzymes or tissue TBARS except a moderate reduction in serum triacyl glycerols. DADBDS feeding to rats maintained on a high lipid diet could also reduce the serum and tissue lipid levels and also reduce the serum transaminases. DADBDS which is an aliphatic disulphide could produce hypolipidemic effects in rats fed a single large dose of ethanol, whereas dimenthol disulphide which is an aromatic disulphide was not useful as a hypolipidemic agent. Perhaps hypolipidemic effects are shown only by aliphatic disulphides and not by aromatic disulphides. Feeding of 100 mg DADBDS per kg body weight to normal fasted rats produced a mild hypoglycemia, but higher doses produced a hyperglycemic effect. This dose of DADBDS increased the serum insulin levels and reduced blood glucose levels in fasted diabetic rats, but DADBDS feeding did not alter the serum insulin levels in fasted normal rats. DADBDS is odourless and tasteless in 1% solution and it could be a better substitute for garlic for hypoglycemic and hypolipidemic studies.  相似文献   

17.
Oxidative stress was assesed by estimating lipid peroxidation product (LPO) in the form of thiobarbituric acid reactive substances (TBARS), enzymatic antioxidants in the form of superoxide dismutase (SOD), catalase and nonenzymatic antioxidant vitamins e.g. vitamin C, β carotene and vitamin E in either serum or plasma or erythrocytes in 190 cases of age related cataract in the age group of 50–80 years. 190 cases were grouped into three morphological types namely, 73 cases of cortical, 77 cases of posterior subcapsular and 40 cases of nuclear cataract and values of LPO and antioxidants were compared with 78 cases of age matched healthy control groups. Plasma TBARS levels were cataract cases when compared with control groups. There were no significant differences in the erythrocyte levels of catalase and plasma levels of Vit E between cataract cases and control groups. No significant changes of parameters were seen among three different morphological types of age related cataract. The present study shows that the oxidative stress may play an important role in the age related cataract.  相似文献   

18.
Alcohol induced effects on kidney   总被引：1，自引：1，他引：0  
After administration ethanol and its metabolites go through kidneys and are excreted into urine, and its content in the urine is higher than that of the blood and the liver. Chronic ethanol administration decreases the renal tubular reabsorption and reduces renal function. Multiple functional abnormalities of renal tubules may be associated with ethanol-induced changes in membrane composition and lipid peroxidation. The vulnerability of the kidney to oxidative damage has been partly attributed to its high content of long-chain polyunsaturated fatty acids. Renal ultra structural abnormalities due to ethanol exposure may be important in the genesis of functional disturbances. Increased oxidative stress and endothelial dysfunction with their complex interrelationships are relevant aspects of atherogenesis in chronic renal failure. Antioxidants, particularly polyphenols are expected to decrease the vulnerability of the kidney to oxidative challenges.  相似文献   

19.
Coconut oil has been used by the people of Kerala as a cooking medium for several decades. Due to its alleged hypercholesterolemic activity, general population in recent times is shifting to cooking oils rich in polyunsaturated fats, the most popular being sunflower oil. The effect of long-term consumption of sunflower oil on oxidative stress in humans is not well investigated. We studied oxidative stress among coronary artery disease (CAD) patients who were consuming coconut oil or sunflower oil as a part of their routine diet. Men, aged 35–70 years, with established CAD, who presented to the hospital for routine cardiac evaluations, were enrolled in this observational study. Group 1 and 2 consisted of 73 and 80 subjects consuming coconut oil and sunflower oil respectively for over a period of 2 years. Lipid profile and parameters for oxidative stress were evaluated among them. Conventional lipid parameters did not differ significantly between the two groups. Mean vitamin C concentration was significantly reduced for subjects on sunflower oil compared to those consuming coconut oil (P = 0.044). Malondialdehyde was higher for sunflower oil consumers compared to coconut oil consumers (P < 0.0001). Other parameters such as oxidized LDL, GSH, GPx and SOD were not found to be significantly different between the two groups. The results of the present study show that coconut oil did not induce hypercholesterolemia compared to sunflower oil. On the other hand, sunflower oil group had elevated oxidative stress compared to coconut oil group.  相似文献   

20.
Oxidative stress has been found to play important role in several neuropsychiatric diseases including Obsessive Compulsive Disorder. A longitudinal case control study was conducted to evaluate the oxidative stress in 30 newly diagnosed obsessive compulsive disorder patients and same number of control patients. Serum thiobarbituric acid reacting substances, plasma ascorbate were assessed to evaluate oxidative stress and Yale Brown obsessive compulsive scale for disease severity before and after treatment with Fluoxetine at the average dosage of 40 mg/day. Improvement in Yale Brown obsessive compulsive scale score by about 43% after 12 weeks treatment was associated with significantly decreased thiobarbituric acid reacting substances and increased plasma ascorbate values (p < 0.05). The newly diagnosed obsessive compulsive disorder patients had higher serum thiobarbituric acid reacting substances as well as a lower plasma ascorbate levels than the control population. Thus, the present study suggested a significant role of oxidative stress in obsessive compulsive disorder and showed that a successful treatment with Fluoxetine not only improves the clinical scenario but also reduces the oxidative stress that may further improve the prognosis of the disease.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号